For new codeStyle in nacos-api module (#3190)

api/pom.xml

@@ -15,18 +15,18 @@
   ~ limitations under the License.
   -->
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <parent>
         <groupId>com.alibaba.nacos</groupId>
         <artifactId>nacos-all</artifactId>
         <version>1.3.0</version>
     </parent>
-
+    
     <modelVersion>4.0.0</modelVersion>
-
+    
     <artifactId>nacos-api</artifactId>
     <packaging>jar</packaging>
-
+    
     <name>nacos-api ${project.version}</name>
     <url>http://nacos.io</url>
     <build>
@@ -41,11 +41,11 @@
             </plugin>
         </plugins>
     </build>
-
+    
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
-
+    
     <dependencies>
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>

api/src/main/java/com/alibaba/nacos/api/NacosFactory.java

@@ -13,27 +13,28 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.nacos.api;
 
-import java.util.Properties;
+package com.alibaba.nacos.api;
 
 import com.alibaba.nacos.api.config.ConfigFactory;
 import com.alibaba.nacos.api.config.ConfigService;
 import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.api.naming.NamingFactory;
 import com.alibaba.nacos.api.naming.NamingMaintainFactory;
 import com.alibaba.nacos.api.naming.NamingMaintainService;
-import com.alibaba.nacos.api.naming.NamingFactory;
 import com.alibaba.nacos.api.naming.NamingService;
 
+import java.util.Properties;
+
 /**
- * Nacos Factory
+ * Nacos Factory.
  *
  * @author Nacos
  */
 public class NacosFactory {
-
+    
     /**
-     * Create config service
+     * Create config service.
      *
      * @param properties init param
      * @return config
@@ -42,9 +43,9 @@ public class NacosFactory {
     public static ConfigService createConfigService(Properties properties) throws NacosException {
         return ConfigFactory.createConfigService(properties);
     }
-
+    
     /**
-     * Create config service
+     * Create config service.
      *
      * @param serverAddr server list
      * @return config
@@ -53,9 +54,9 @@ public class NacosFactory {
     public static ConfigService createConfigService(String serverAddr) throws NacosException {
         return ConfigFactory.createConfigService(serverAddr);
     }
-
+    
     /**
-     * Create naming service
+     * Create naming service.
      *
      * @param serverAddr server list
      * @return Naming
@@ -64,9 +65,9 @@ public class NacosFactory {
     public static NamingService createNamingService(String serverAddr) throws NacosException {
         return NamingFactory.createNamingService(serverAddr);
     }
-
+    
     /**
-     * Create naming service
+     * Create naming service.
      *
      * @param properties init param
      * @return Naming
@@ -75,22 +76,22 @@ public class NacosFactory {
     public static NamingService createNamingService(Properties properties) throws NacosException {
         return NamingFactory.createNamingService(properties);
     }
-
+    
     /**
-     * Create maintain service
+     * Create maintain service.
      *
-     * @param serverAddr
+     * @param serverAddr server address
      * @return NamingMaintainService
      * @throws NacosException Exception
      */
     public static NamingMaintainService createMaintainService(String serverAddr) throws NacosException {
         return NamingMaintainFactory.createMaintainService(serverAddr);
     }
-
+    
     /**
-     * Create maintain service
+     * Create maintain service.
      *
-     * @param properties
+     * @param properties server address
      * @return NamingMaintainService
      * @throws NacosException Exception
      */

api/src/main/java/com/alibaba/nacos/api/PropertyKeyConst.java

@@ -13,67 +13,68 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api;
 
 /**
- * Property Key Const
+ * Property Key Const.
  *
  * @author Nacos
  */
 public class PropertyKeyConst {
-
+    
-    public final static String IS_USE_CLOUD_NAMESPACE_PARSING = "isUseCloudNamespaceParsing";
+    public static final String IS_USE_CLOUD_NAMESPACE_PARSING = "isUseCloudNamespaceParsing";
-
+    
-    public final static String IS_USE_ENDPOINT_PARSING_RULE = "isUseEndpointParsingRule";
+    public static final String IS_USE_ENDPOINT_PARSING_RULE = "isUseEndpointParsingRule";
-
+    
-    public final static String ENDPOINT = "endpoint";
+    public static final String ENDPOINT = "endpoint";
-
+    
-    public final static String ENDPOINT_PORT = "endpointPort";
+    public static final String ENDPOINT_PORT = "endpointPort";
-
+    
-    public final static String NAMESPACE = "namespace";
+    public static final String NAMESPACE = "namespace";
-
+    
-    public final static String USERNAME = "username";
+    public static final String USERNAME = "username";
-
+    
-    public final static String PASSWORD = "password";
+    public static final String PASSWORD = "password";
-
+    
-    public final static String ACCESS_KEY = "accessKey";
+    public static final String ACCESS_KEY = "accessKey";
-
+    
-    public final static String SECRET_KEY = "secretKey";
+    public static final String SECRET_KEY = "secretKey";
-
+    
-    public final static String RAM_ROLE_NAME = "ramRoleName";
+    public static final String RAM_ROLE_NAME = "ramRoleName";
-
+    
-    public final static String SERVER_ADDR = "serverAddr";
+    public static final String SERVER_ADDR = "serverAddr";
-
+    
-    public final static String CONTEXT_PATH = "contextPath";
+    public static final String CONTEXT_PATH = "contextPath";
-
+    
-    public final static String CLUSTER_NAME = "clusterName";
+    public static final String CLUSTER_NAME = "clusterName";
-
+    
-    public final static String ENCODE = "encode";
+    public static final String ENCODE = "encode";
-
+    
-    public final static String CONFIG_LONG_POLL_TIMEOUT = "configLongPollTimeout";
+    public static final String CONFIG_LONG_POLL_TIMEOUT = "configLongPollTimeout";
-
+    
-    public final static String CONFIG_RETRY_TIME = "configRetryTime";
+    public static final String CONFIG_RETRY_TIME = "configRetryTime";
-
+    
-    public final static String MAX_RETRY = "maxRetry";
+    public static final String MAX_RETRY = "maxRetry";
-
+    
-    public final static String ENABLE_REMOTE_SYNC_CONFIG = "enableRemoteSyncConfig";
+    public static final String ENABLE_REMOTE_SYNC_CONFIG = "enableRemoteSyncConfig";
-
+    
-    public final static String NAMING_LOAD_CACHE_AT_START = "namingLoadCacheAtStart";
+    public static final String NAMING_LOAD_CACHE_AT_START = "namingLoadCacheAtStart";
-
+    
-    public final static String NAMING_CLIENT_BEAT_THREAD_COUNT = "namingClientBeatThreadCount";
+    public static final String NAMING_CLIENT_BEAT_THREAD_COUNT = "namingClientBeatThreadCount";
-
+    
-    public final static String NAMING_POLLING_THREAD_COUNT = "namingPollingThreadCount";
+    public static final String NAMING_POLLING_THREAD_COUNT = "namingPollingThreadCount";
-
+    
     /**
-     * Get the key value of some variable value from the system property
+     * Get the key value of some variable value from the system property.
      */
     public static class SystemEnv {
-
+        
         public static final String ALIBABA_ALIWARE_ENDPOINT_PORT = "ALIBABA_ALIWARE_ENDPOINT_PORT";
-
+        
         public static final String ALIBABA_ALIWARE_NAMESPACE = "ALIBABA_ALIWARE_NAMESPACE";
-
+        
         public static final String ALIBABA_ALIWARE_ENDPOINT_URL = "ALIBABA_ALIWARE_ENDPOINT_URL";
     }
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/SystemPropertyKeyConst.java

@@ -13,38 +13,37 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api;
 
 /**
- * <p>
+ * Support for reading the value of the specified variable from the -D parameter.
- * Support for reading the value of the specified variable from the -D parameter
+ *
- * </P>
+ * <p>Properties that are preferred to which in {@link PropertyKeyConst}
- * Properties that are preferred to which in {@link PropertyKeyConst}
  *
  * @author pbting
- * @date 2019-02-22 3:38 PM
  */
 public interface SystemPropertyKeyConst {
-
+    
     String NAMING_SERVER_PORT = "nacos.naming.exposed.port";
-
+    
     String NAMING_WEB_CONTEXT = "nacos.naming.web.context";
-
+    
     /**
-     * In the cloud (Alibaba Cloud or other cloud vendors) environment,
+     * In the cloud (Alibaba Cloud or other cloud vendors) environment, whether to enable namespace resolution in the
-     * whether to enable namespace resolution in the cloud environment.
+     * cloud environment.
      * <p>
      * The default is on.
      * </p>
      */
     String IS_USE_CLOUD_NAMESPACE_PARSING = "nacos.use.cloud.namespace.parsing";
-
+    
     /**
-     * In the cloud environment, if the process level requires a globally uniform namespace,
+     * In the cloud environment, if the process level requires a globally uniform namespace, it can be specified with
-     * it can be specified with the -D parameter.
+     * the -D parameter.
      */
     String ANS_NAMESPACE = "ans.namespace";
-
+    
     /**
      * It is also supported by the -D parameter.
      */

api/src/main/java/com/alibaba/nacos/api/annotation/NacosInjected.java

@@ -13,12 +13,17 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.annotation;
 
 import com.alibaba.nacos.api.config.ConfigService;
 import com.alibaba.nacos.api.naming.NamingService;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 /**
  * An annotation to inject {@link ConfigService} or {@link NamingService} instance into the target Bean.
@@ -33,12 +38,12 @@ import java.lang.annotation.*;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 public @interface NacosInjected {
-
+    
     /**
      * The {@link NacosProperties} attribute, If not specified, it will use global Nacos Properties.
      *
      * @return the default value is {@link NacosProperties}
      */
     NacosProperties properties() default @NacosProperties;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/annotation/NacosProperties.java

@@ -13,14 +13,19 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.annotation;
 
 import com.alibaba.nacos.api.PropertyKeyConst;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 /**
- * An annotation for Nacos Properties
+ * An annotation for Nacos Properties.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  * @see PropertyKeyConst
@@ -30,263 +35,266 @@ import java.lang.annotation.*;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 public @interface NacosProperties {
-
+    
     /**
-     * The prefix of property name of Nacos
+     * The prefix of property name of Nacos.
      */
     String PREFIX = "nacos.";
-
+    
     /**
-     * The property name of "endpoint"
+     * The property name of "endpoint".
      */
     String ENDPOINT = "endpoint";
-
+    
     /**
-     * The property name of "namespace"
+     * The property name of "namespace".
      */
     String NAMESPACE = "namespace";
-
+    
     /**
-     * The property name of "access-key"
+     * The property name of "access-key".
      */
     String ACCESS_KEY = "access-key";
-
+    
     /**
-     * The property name of "secret-key"
+     * The property name of "secret-key".
      */
     String SECRET_KEY = "secret-key";
-
+    
     /**
-     * The property name of "server-addr"
+     * The property name of "server-addr".
      */
     String SERVER_ADDR = "server-addr";
-
+    
     /**
-     * The property name of "context-path"
+     * The property name of "context-path".
      */
     String CONTEXT_PATH = "context-path";
-
+    
     /**
-     * The property name of "cluster-name"
+     * The property name of "cluster-name".
      */
     String CLUSTER_NAME = "cluster-name";
-
+    
     /**
-     * The property name of "encode"
+     * The property name of "encode".
      */
     String ENCODE = "encode";
-
+    
     /**
-     * The property name of "long-poll.timeout"
+     * The property name of "long-poll.timeout".
      */
     String CONFIG_LONG_POLL_TIMEOUT = "configLongPollTimeout";
-
+    
     /**
-     * The property name of "config.retry.time"
+     * The property name of "config.retry.time".
      */
     String CONFIG_RETRY_TIME = "configRetryTime";
-
+    
     /**
-     * The property name of "maxRetry"
+     * The property name of "maxRetry".
      */
     String MAX_RETRY = "maxRetry";
-
+    
     /**
-     * The property name of "enableRemoteSyncConfig"
+     * The property name of "enableRemoteSyncConfig".
      */
     String ENABLE_REMOTE_SYNC_CONFIG = "enableRemoteSyncConfig";
-
+    
     /**
-     * The property name of "username"
+     * The property name of "username".
      */
     String USERNAME = "username";
-
+    
     /**
-     * The property name of "password"
+     * The property name of "password".
      */
     String PASSWORD = "password";
-
+    
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.endpoint:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.endpoint:}"</code>.
      */
     String ENDPOINT_PLACEHOLDER = "${" + PREFIX + ENDPOINT + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.namespace:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.namespace:}"</code>.
      */
     String NAMESPACE_PLACEHOLDER = "${" + PREFIX + NAMESPACE + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.access-key:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.access-key:}"</code>.
      */
     String ACCESS_KEY_PLACEHOLDER = "${" + PREFIX + ACCESS_KEY + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.secret-key:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.secret-key:}"</code>.
      */
     String SECRET_KEY_PLACEHOLDER = "${" + PREFIX + SECRET_KEY + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>${nacos.server-addr:}"</code>
+     * The placeholder of endpoint, the value is <code>${nacos.server-addr:}"</code>.
      */
     String SERVER_ADDR_PLACEHOLDER = "${" + PREFIX + SERVER_ADDR + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is ${nacos.context-path:}"
+     * The placeholder of endpoint, the value is ${nacos.context-path:}".
      */
     String CONTEXT_PATH_PLACEHOLDER = "${" + PREFIX + CONTEXT_PATH + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.cluster-name:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.cluster-name:}"</code>.
      */
     String CLUSTER_NAME_PLACEHOLDER = "${" + PREFIX + CLUSTER_NAME + ":}";
-
+    
     /**
-     * The placeholder of {@link NacosProperties#ENCODE encode}, the value is <code>"${nacos.encode:UTF-8}"</code>
+     * The placeholder of {@link NacosProperties#ENCODE encode}, the value is <code>"${nacos.encode:UTF-8}"</code>.
      */
     String ENCODE_PLACEHOLDER = "${" + PREFIX + ENCODE + ":UTF-8}";
-
+    
     /**
-     * The placeholder of {@link NacosProperties#CONFIG_LONG_POLL_TIMEOUT configLongPollTimeout}, the value is <code>"${nacos.configLongPollTimeout:}"</code>
+     * The placeholder of {@link NacosProperties#CONFIG_LONG_POLL_TIMEOUT configLongPollTimeout}, the value is
+     * <code>"${nacos.configLongPollTimeout:}"</code>.
      */
     String CONFIG_LONG_POLL_TIMEOUT_PLACEHOLDER = "${" + PREFIX + CONFIG_LONG_POLL_TIMEOUT + ":}";
-
+    
     /**
-     * The placeholder of {@link NacosProperties#CONFIG_RETRY_TIME configRetryTime}, the value is <code>"${nacos.configRetryTime:}"</code>
+     * The placeholder of {@link NacosProperties#CONFIG_RETRY_TIME configRetryTime}, the value is
+     * <code>"${nacos.configRetryTime:}"</code>.
      */
     String CONFIG_RETRY_TIME_PLACEHOLDER = "${" + PREFIX + CONFIG_RETRY_TIME + ":}";
-
+    
     /**
-     * The placeholder of {@link NacosProperties#MAX_RETRY maxRetry}, the value is <code>"${nacos.maxRetry:}"</code>
+     * The placeholder of {@link NacosProperties#MAX_RETRY maxRetry}, the value is <code>"${nacos.maxRetry:}"</code>.
      */
     String MAX_RETRY_PLACEHOLDER = "${" + PREFIX + MAX_RETRY + ":}";
-
+    
     /**
-     * The placeholder of {@link NacosProperties#ENABLE_REMOTE_SYNC_CONFIG enableRemoteSyncConfig}, the value is <code>"${nacos.enableRemoteSyncConfig:}"</code>
+     * The placeholder of {@link NacosProperties#ENABLE_REMOTE_SYNC_CONFIG enableRemoteSyncConfig}, the value is
+     * <code>"${nacos.enableRemoteSyncConfig:}"</code>.
      */
     String ENABLE_REMOTE_SYNC_CONFIG_PLACEHOLDER = "${" + PREFIX + ENABLE_REMOTE_SYNC_CONFIG + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.username:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.username:}"</code>.
      */
     String USERNAME_PLACEHOLDER = "${" + PREFIX + USERNAME + ":}";
-
+    
     /**
-     * The placeholder of endpoint, the value is <code>"${nacos.password:}"</code>
+     * The placeholder of endpoint, the value is <code>"${nacos.password:}"</code>.
      */
     String PASSWORD_PLACEHOLDER = "${" + PREFIX + PASSWORD + ":}";
-
+    
     /**
-     * The property of "endpoint"
+     * The property of "endpoint".
      *
      * @return empty as default value
      * @see #ENDPOINT_PLACEHOLDER
      */
     String endpoint() default ENDPOINT_PLACEHOLDER;
-
+    
     /**
-     * The property of "namespace"
+     * The property of "namespace".
      *
      * @return empty as default value
      * @see #NAMESPACE_PLACEHOLDER
      */
     String namespace() default NAMESPACE_PLACEHOLDER;
-
+    
     /**
-     * The property of "access-key"
+     * The property of "access-key".
      *
      * @return empty as default value
      * @see #ACCESS_KEY_PLACEHOLDER
      */
     String accessKey() default ACCESS_KEY_PLACEHOLDER;
-
+    
     /**
-     * The property of "secret-key"
+     * The property of "secret-key".
      *
      * @return empty as default value
      * @see #SECRET_KEY_PLACEHOLDER
      */
     String secretKey() default SECRET_KEY_PLACEHOLDER;
-
+    
     /**
-     * The property of "server-addr"
+     * The property of "server-addr".
      *
      * @return empty as default value
      * @see #SERVER_ADDR_PLACEHOLDER
      */
     String serverAddr() default SERVER_ADDR_PLACEHOLDER;
-
+    
     /**
-     * The property of "context-path"
+     * The property of "context-path".
      *
      * @return empty as default value
      * @see #CONTEXT_PATH_PLACEHOLDER
      */
     String contextPath() default CONTEXT_PATH_PLACEHOLDER;
-
+    
     /**
-     * The property of "cluster-name"
+     * The property of "cluster-name".
      *
      * @return empty as default value
      * @see #CLUSTER_NAME_PLACEHOLDER
      */
     String clusterName() default CLUSTER_NAME_PLACEHOLDER;
-
+    
     /**
-     * The property of "encode"
+     * The property of "encode".
      *
      * @return "UTF-8" as default value
      * @see #ENCODE_PLACEHOLDER
      */
     String encode() default ENCODE_PLACEHOLDER;
-
+    
     /**
-     * The property of "configLongPollTimeout"
+     * The property of "configLongPollTimeout".
      *
      * @return empty as default value
      * @see #CONFIG_LONG_POLL_TIMEOUT_PLACEHOLDER
      */
     String configLongPollTimeout() default CONFIG_LONG_POLL_TIMEOUT_PLACEHOLDER;
-
+    
     /**
-     * The property of "configRetryTime"
+     * The property of "configRetryTime".
      *
      * @return empty as default value
      * @see #CONFIG_RETRY_TIME_PLACEHOLDER
      */
     String configRetryTime() default CONFIG_RETRY_TIME_PLACEHOLDER;
-
+    
     /**
-     * The property of "maxRetry"
+     * The property of "maxRetry".
      *
      * @return empty as default value
      * @see #MAX_RETRY
      */
     String maxRetry() default MAX_RETRY_PLACEHOLDER;
-
+    
     /**
-     * The property of "enableRemoteSyncConfig"
+     * The property of "enableRemoteSyncConfig".
      *
      * @return empty as default value
      * @see #ENABLE_REMOTE_SYNC_CONFIG
      */
     String enableRemoteSyncConfig() default ENABLE_REMOTE_SYNC_CONFIG_PLACEHOLDER;
-
+    
     /**
-     * The property of "username"
+     * The property of "username".
      *
      * @return empty as default value
      * @see #USERNAME_PLACEHOLDER
      */
     String username() default USERNAME_PLACEHOLDER;
-
+    
     /**
-     * The property of "password"
+     * The property of "password".
      *
      * @return empty as default value
      * @see #PASSWORD_PLACEHOLDER
      */
     String password() default PASSWORD_PLACEHOLDER;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/cmdb/pojo/Entity.java

@@ -13,40 +13,45 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.cmdb.pojo;
 
 import java.util.Map;
 
 /**
+ * CMDB entity.
+ *
  * @author nkorange
  * @since 0.7.0
  */
 public class Entity {
-
+    
     private String type;
+    
     private String name;
+    
     private Map<String, String> labels;
-
+    
     public String getType() {
         return type;
     }
-
+    
     public void setType(String type) {
         this.type = type;
     }
-
+    
     public String getName() {
         return name;
     }
-
+    
     public void setName(String name) {
         this.name = name;
     }
-
+    
     public Map<String, String> getLabels() {
         return labels;
     }
-
+    
     public void setLabels(Map<String, String> labels) {
         this.labels = labels;
     }

api/src/main/java/com/alibaba/nacos/api/cmdb/pojo/EntityEvent.java

@@ -13,38 +13,43 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.cmdb.pojo;
 
 /**
+ * CMDB entity event.
+ *
  * @author nkorange
  * @since 0.7.0
  */
 public class EntityEvent {
-
+    
     private EntityEventType type;
+    
     private String entityName;
+    
     private String entityType;
-
+    
     public EntityEventType getType() {
         return type;
     }
-
+    
     public void setType(EntityEventType type) {
         this.type = type;
     }
-
+    
     public String getEntityName() {
         return entityName;
     }
-
+    
     public void setEntityName(String entityName) {
         this.entityName = entityName;
     }
-
+    
     public String getEntityType() {
         return entityType;
     }
-
+    
     public void setEntityType(String entityType) {
         this.entityType = entityType;
     }

api/src/main/java/com/alibaba/nacos/api/cmdb/pojo/EntityEventType.java

@@ -13,19 +13,23 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.cmdb.pojo;
 
 /**
+ * CMDB entity event type.
+ *
  * @author nkorange
  * @since 0.7.0
  */
 public enum EntityEventType {
+    
     /**
-     *
+     * Add or update entity.
      */
     ENTITY_ADD_OR_UPDATE,
     /**
-     *
+     * Remove entity.
      */
     ENTITY_REMOVE
 }

api/src/main/java/com/alibaba/nacos/api/cmdb/pojo/Label.java

@@ -13,40 +13,45 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.cmdb.pojo;
 
 import java.util.Set;
 
 /**
+ * CMDB lable.
+ *
  * @author nkorange
  * @since 0.7.0
  */
 public class Label {
-
+    
     private String name;
+    
     private Set<String> values;
+    
     private String description;
-
+    
     public String getName() {
         return name;
     }
-
+    
     public void setName(String name) {
         this.name = name;
     }
-
+    
     public Set<String> getValues() {
         return values;
     }
-
+    
     public void setValues(Set<String> values) {
         this.values = values;
     }
-
+    
     public String getDescription() {
         return description;
     }
-
+    
     public void setDescription(String description) {
         this.description = description;
     }

api/src/main/java/com/alibaba/nacos/api/cmdb/pojo/PreservedEntityTypes.java

@@ -13,19 +13,22 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.cmdb.pojo;
 
 /**
+ * CMDB preserverd entity type.
+ *
  * @author nkorange
  * @since 0.7.0
  */
 public enum PreservedEntityTypes {
     /**
-     * Ip
+     * Ip.
      */
     ip,
     /**
-     * Service
+     * Service.
      */
     service
 }

api/src/main/java/com/alibaba/nacos/api/cmdb/spi/CmdbService.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.cmdb.spi;
 
 import com.alibaba.nacos.api.cmdb.pojo.Entity;
@@ -24,71 +25,71 @@ import java.util.Map;
 import java.util.Set;
 
 /**
- * Service to visit CMDB store
+ * Service to visit CMDB store.
  *
  * @author nkorange
  * @since 0.7.0
  */
 public interface CmdbService {
-
+    
     /**
-     * Get all label names stored in CMDB
+     * Get all label names stored in CMDB.
      *
      * @return label name set
      */
     Set<String> getLabelNames();
-
+    
     /**
-     * Get all possible entity types in CMDB
+     * Get all possible entity types in CMDB.
      *
      * @return all entity types
      */
     Set<String> getEntityTypes();
-
+    
     /**
-     * Get label info
+     * Get label info.
      *
      * @param labelName label name
      * @return label info
      */
     Label getLabel(String labelName);
-
+    
     /**
-     * Get label value of label name of ip
+     * Get label value of label name of ip.
      *
      * @param entityName entity name
-     * @param entityType  entity type
+     * @param entityType entity type
-     * @param labelName   target label name
+     * @param labelName  target label name
      * @return label value
      */
     String getLabelValue(String entityName, String entityType, String labelName);
-
+    
     /**
-     * Get all label value of ip
+     * Get all label value of ip.
      *
      * @param entityName entity name
-     * @param entityType  entity type
+     * @param entityType entity type
      * @return all label values
      */
     Map<String, String> getLabelValues(String entityName, String entityType);
-
+    
     /**
-     * Dump all entities in CMDB
+     * Dump all entities in CMDB.
      *
      * @return all entities
      */
     Map<String, Map<String, Entity>> getAllEntities();
-
+    
     /**
-     * get label change events
+     * get label change events.
      *
      * @param timestamp start time of generated events
      * @return label events
      */
     List<EntityEvent> getEntityEvents(long timestamp);
-
+    
     /**
-     * Get single entity
+     * Get single entity.
      *
      * @param entityName name of entity
      * @param entityType type of entity

api/src/main/java/com/alibaba/nacos/api/common/Constants.java

@@ -13,174 +13,179 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.common;
 
 import java.util.concurrent.TimeUnit;
 
 /**
- * Constant
+ * Constants.
  *
  * @author Nacos
  */
 public class Constants {
-
+    
     public static final String CLIENT_VERSION = "3.0.0";
-
+    
-    public static int DATA_IN_BODY_VERSION = 204;
+    public static final int DATA_IN_BODY_VERSION = 204;
-
+    
     public static final String DEFAULT_GROUP = "DEFAULT_GROUP";
-
+    
     public static final String APPNAME = "AppName";
-
+    
     public static final String UNKNOWN_APP = "UnknownApp";
-
+    
     public static final String DEFAULT_DOMAINNAME = "commonconfig.config-host.taobao.com";
-
+    
     public static final String DAILY_DOMAINNAME = "commonconfig.taobao.net";
-
+    
     public static final String NULL = "";
-
+    
     public static final String DATAID = "dataId";
-
+    
     public static final String GROUP = "group";
-
+    
     public static final String LAST_MODIFIED = "Last-Modified";
-
+    
     public static final String ACCEPT_ENCODING = "Accept-Encoding";
-
+    
     public static final String CONTENT_ENCODING = "Content-Encoding";
-
+    
     public static final String PROBE_MODIFY_REQUEST = "Listening-Configs";
-
+    
     public static final String PROBE_MODIFY_RESPONSE = "Probe-Modify-Response";
-
+    
     public static final String PROBE_MODIFY_RESPONSE_NEW = "Probe-Modify-Response-New";
-
+    
     public static final String USE_ZIP = "true";
-
+    
     public static final String CONTENT_MD5 = "Content-MD5";
-
+    
     public static final String CONFIG_VERSION = "Config-Version";
-
+    
     public static final String CONFIG_TYPE = "Config-Type";
-
+    
     public static final String IF_MODIFIED_SINCE = "If-Modified-Since";
-
+    
     public static final String SPACING_INTERVAL = "client-spacing-interval";
-
+    
     public static final String BASE_PATH = "/v1/cs";
-
+    
     public static final String CONFIG_CONTROLLER_PATH = BASE_PATH + "/configs";
-
+    
     public static final String TOKEN = "token";
-
+    
     public static final String ACCESS_TOKEN = "accessToken";
-
+    
     public static final String TOKEN_TTL = "tokenTtl";
-
+    
     public static final String GLOBAL_ADMIN = "globalAdmin";
-
+    
     public static final String TOKEN_REFRESH_WINDOW = "tokenRefreshWindow";
-
+    
     /**
-     * second
+     * second.
      */
     public static final int ASYNC_UPDATE_ADDRESS_INTERVAL = 300;
-
+    
     /**
-     * second
+     * second.
      */
     public static final int POLLING_INTERVAL_TIME = 15;
-
+    
     /**
-     * millisecond
+     * millisecond.
      */
     public static final int ONCE_TIMEOUT = 2000;
-
+    
     /**
-     * millisecond
+     * millisecond.
      */
     public static final int SO_TIMEOUT = 60000;
-
+    
     /**
-     * millisecond
+     * millisecond.
      */
     public static final int CONFIG_LONG_POLL_TIMEOUT = 30000;
-
+    
     /**
-     * millisecond
+     * millisecond.
      */
     public static final int MIN_CONFIG_LONG_POLL_TIMEOUT = 10000;
-
+    
     /**
-     * millisecond
+     * millisecond.
      */
     public static final int CONFIG_RETRY_TIME = 2000;
-
+    
     /**
-     * Maximum number of retries
+     * Maximum number of retries.
      */
     public static final int MAX_RETRY = 3;
-
+    
     /**
-     * millisecond
+     * millisecond.
      */
     public static final int RECV_WAIT_TIMEOUT = ONCE_TIMEOUT * 5;
-
+    
     public static final String ENCODE = "UTF-8";
-
+    
     public static final String MAP_FILE = "map-file.js";
-
+    
     public static final int FLOW_CONTROL_THRESHOLD = 20;
-
+    
     public static final int FLOW_CONTROL_SLOT = 10;
-
+    
     public static final int FLOW_CONTROL_INTERVAL = 1000;
-
+    
     public static final float DEFAULT_PROTECT_THRESHOLD = 0.0F;
-
+    
     public static final String LINE_SEPARATOR = Character.toString((char) 1);
-
+    
     public static final String WORD_SEPARATOR = Character.toString((char) 2);
-
+    
     public static final String LONGPOLLING_LINE_SEPARATOR = "\r\n";
-
+    
     public static final String CLIENT_APPNAME_HEADER = "Client-AppName";
+    
     public static final String CLIENT_REQUEST_TS_HEADER = "Client-RequestTS";
+    
     public static final String CLIENT_REQUEST_TOKEN_HEADER = "Client-RequestToken";
-
+    
     public static final int ATOMIC_MAX_SIZE = 1000;
-
+    
     public static final String NAMING_INSTANCE_ID_SPLITTER = "#";
+    
     public static final int NAMING_INSTANCE_ID_SEG_COUNT = 4;
+    
     public static final String NAMING_HTTP_HEADER_SPILIER = "\\|";
-
+    
     public static final String DEFAULT_CLUSTER_NAME = "DEFAULT";
-
+    
     public static final long DEFAULT_HEART_BEAT_TIMEOUT = TimeUnit.SECONDS.toMillis(15);
-
+    
     public static final long DEFAULT_IP_DELETE_TIMEOUT = TimeUnit.SECONDS.toMillis(30);
-
+    
     public static final long DEFAULT_HEART_BEAT_INTERVAL = TimeUnit.SECONDS.toMillis(5);
-
+    
     public static final String DEFAULT_NAMESPACE_ID = "public";
-
+    
     public static final boolean DEFAULT_USE_CLOUD_NAMESPACE_PARSING = true;
-
+    
     public static final int WRITE_REDIRECT_CODE = 307;
-
+    
     public static final String SERVICE_INFO_SPLITER = "@@";
-
+    
     public static final String NULL_STRING = "null";
-
+    
     public static final String NUMBER_PATTERN = "^\\d+$";
-
+    
     public static final String ANY_PATTERN = ".*";
-
+    
     public static final String DEFAULT_INSTANCE_ID_GENERATOR = "simple";
-
+    
     public static final String SNOWFLAKE_INSTANCE_ID_GENERATOR = "snowflake";
-
+    
     public static final String HTTP_PREFIX = "http";
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/common/ResponseCode.java

@@ -13,14 +13,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.nacos.api.common;
 
+package com.alibaba.nacos.api.common;
 
 /**
  * Response code definitions.
- * <p>
+ *
- * This class and inherited classes define codes separated from HTTP code to provide richer and preciser
+ * <p>This class and inherited classes define codes separated from HTTP code to provide richer and preciser information of
- * information of the API results. A recommended rule for defining response code is:
+ * the API results. A recommended rule for defining response code is:
  * <li> Global and common code starts with 10001.
  * <li> Naming module code starts with 20001.
  * <li> Config module code starts with 30001.
@@ -29,9 +29,9 @@ package com.alibaba.nacos.api.common;
  * @since 1.2.0
  */
 public class ResponseCode {
-
+    
     /**
-     * Everything normal
+     * Everything normal.
      */
     public static final int OK = 10200;
 }

api/src/main/java/com/alibaba/nacos/api/config/ConfigChangeEvent.java

@@ -13,32 +13,32 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.nacos.api.config;
 
-import com.alibaba.nacos.api.config.ConfigChangeItem;
+package com.alibaba.nacos.api.config;
 
 import java.util.Collection;
 import java.util.Map;
 
 /**
- * ConfigChangeEvent
+ * ConfigChangeEvent.
  *
  * @author rushsky518
  */
 public class ConfigChangeEvent {
-    private Map<String, ConfigChangeItem> data;
+    
-
+    private final Map<String, ConfigChangeItem> data;
+    
     public ConfigChangeEvent(Map<String, ConfigChangeItem> data) {
         this.data = data;
     }
-
+    
     public ConfigChangeItem getChangeItem(String key) {
         return data.get(key);
     }
-
+    
     public Collection<ConfigChangeItem> getChangeItems() {
         return data.values();
     }
-
+    
 }
 

api/src/main/java/com/alibaba/nacos/api/config/ConfigChangeItem.java

@@ -13,65 +13,65 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config;
 
 /**
- * ConfigChangeItem
+ * ConfigChangeItem.
  *
  * @author rushsky518
  */
 public class ConfigChangeItem {
+    
     private String key;
+    
     private String oldValue;
+    
     private String newValue;
-
+    
     private PropertyChangeType type;
-
+    
     public ConfigChangeItem(String key, String oldValue, String newValue) {
         this.key = key;
         this.oldValue = oldValue;
         this.newValue = newValue;
     }
-
+    
     public String getKey() {
         return key;
     }
-
+    
     public void setKey(String key) {
         this.key = key;
     }
-
+    
     public String getOldValue() {
         return oldValue;
     }
-
+    
     public void setOldValue(String oldValue) {
         this.oldValue = oldValue;
     }
-
+    
     public String getNewValue() {
         return newValue;
     }
-
+    
     public void setNewValue(String newValue) {
         this.newValue = newValue;
     }
-
+    
     public PropertyChangeType getType() {
         return type;
     }
-
+    
     public void setType(PropertyChangeType type) {
         this.type = type;
     }
-
+    
     @Override
     public String toString() {
-        return "ConfigChangeItem{" +
+        return "ConfigChangeItem{" + "key='" + key + '\'' + ", oldValue='" + oldValue + '\'' + ", newValue='" + newValue
-            "key='" + key + '\'' +
+                + '\'' + ", type=" + type + '}';
-            ", oldValue='" + oldValue + '\'' +
-            ", newValue='" + newValue + '\'' +
-            ", type=" + type +
-            '}';
     }
 }

api/src/main/java/com/alibaba/nacos/api/config/ConfigFactory.java

@@ -13,23 +13,24 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.nacos.api.config;
 
-import java.lang.reflect.Constructor;
+package com.alibaba.nacos.api.config;
-import java.util.Properties;
 
 import com.alibaba.nacos.api.PropertyKeyConst;
 import com.alibaba.nacos.api.exception.NacosException;
 
+import java.lang.reflect.Constructor;
+import java.util.Properties;
+
 /**
- * Config Factory
+ * Config Factory.
  *
  * @author Nacos
  */
 public class ConfigFactory {
-
+    
     /**
-     * Create Config
+     * Create Config.
      *
      * @param properties init param
      * @return ConfigService
@@ -45,9 +46,9 @@ public class ConfigFactory {
             throw new NacosException(NacosException.CLIENT_INVALID_PARAM, e);
         }
     }
-
+    
     /**
-     * Create Config
+     * Create Config.
      *
      * @param serverAddr serverList
      * @return Config

api/src/main/java/com/alibaba/nacos/api/config/ConfigService.java

@@ -13,20 +13,21 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config;
 
 import com.alibaba.nacos.api.config.listener.Listener;
 import com.alibaba.nacos.api.exception.NacosException;
 
 /**
- * Config Service Interface
+ * Config Service Interface.
  *
  * @author Nacos
  */
 public interface ConfigService {
-
+    
     /**
-     * Get config
+     * Get config.
      *
      * @param dataId    dataId
      * @param group     group
@@ -35,31 +36,30 @@ public interface ConfigService {
      * @throws NacosException NacosException
      */
     String getConfig(String dataId, String group, long timeoutMs) throws NacosException;
-
+    
     /**
-     * Get config and register Listener
+     * Get config and register Listener.
      *
-     * If you want to pull it yourself when the program starts to get the configuration for the first time,
+     * <p>If you want to pull it yourself when the program starts to get the configuration for the first time, and the
-     * and the registered Listener is used for future configuration updates, you can keep the original
+     * registered Listener is used for future configuration updates, you can keep the original code unchanged, just add
-     * code unchanged, just add the system parameter: enableRemoteSyncConfig = "true" ( But there is network overhead);
+     * the system parameter: enableRemoteSyncConfig = "true" ( But there is network overhead); therefore we recommend
-     * therefore we recommend that you use this interface directly
+     * that you use this interface directly
      *
      * @param dataId    dataId
      * @param group     group
      * @param timeoutMs read timeout
-     * @param listener {@link Listener}
+     * @param listener  {@link Listener}
      * @return config value
      * @throws NacosException NacosException
      */
-    String getConfigAndSignListener(String dataId, String group, long timeoutMs, Listener listener) throws NacosException;
+    String getConfigAndSignListener(String dataId, String group, long timeoutMs, Listener listener)
-
+            throws NacosException;
+    
     /**
-     * Add a listener to the configuration, after the server modified the
+     * Add a listener to the configuration, after the server modified the configuration, the client will use the
-     * configuration, the client will use the incoming listener callback.
+     * incoming listener callback. Recommended asynchronous processing, the application can implement the getExecutor
-     * Recommended asynchronous processing, the application can implement the
+     * method in the ManagerListener, provide a thread pool of execution. If provided, use the main thread callback, May
-     * getExecutor method in the ManagerListener, provide a thread pool of
+     * block other configurations or be blocked by other configurations.
-     * execution. If provided, use the main thread callback, May block other
-     * configurations or be blocked by other configurations.
      *
      * @param dataId   dataId
      * @param group    group
@@ -67,7 +67,7 @@ public interface ConfigService {
      * @throws NacosException NacosException
      */
     void addListener(String dataId, String group, Listener listener) throws NacosException;
-
+    
     /**
      * Publish config.
      *
@@ -78,9 +78,9 @@ public interface ConfigService {
      * @throws NacosException NacosException
      */
     boolean publishConfig(String dataId, String group, String content) throws NacosException;
-
+    
     /**
-     * Remove config
+     * Remove config.
      *
      * @param dataId dataId
      * @param group  group
@@ -88,25 +88,25 @@ public interface ConfigService {
      * @throws NacosException NacosException
      */
     boolean removeConfig(String dataId, String group) throws NacosException;
-
+    
     /**
-     * Remove listener
+     * Remove listener.
      *
      * @param dataId   dataId
      * @param group    group
      * @param listener listener
      */
     void removeListener(String dataId, String group, Listener listener);
-
+    
     /**
-     * Get server status
+     * Get server status.
      *
      * @return whether health
      */
     String getServerStatus();
-
+    
     /**
-     * Shutdown the resource service
+     * Shutdown the resource service.
      *
      * @throws NacosException exception.
      */

api/src/main/java/com/alibaba/nacos/api/config/ConfigType.java

@@ -17,47 +17,48 @@
 package com.alibaba.nacos.api.config;
 
 /**
+ * Config data type.
+ *
  * @author liaochuntao
- * @date 2019-06-14 21:12
  **/
 public enum ConfigType {
-
+    
     /**
-     * config type is "properties"
+     * config type is "properties".
      */
     PROPERTIES("properties"),
-
+    
     /**
-     * config type is "xml"
+     * config type is "xml".
      */
     XML("xml"),
-
+    
     /**
-     * config type is "json"
+     * config type is "json".
      */
     JSON("json"),
-
+    
     /**
-     * config type is "text"
+     * config type is "text".
      */
     TEXT("text"),
-
+    
     /**
-     * config type is "html"
+     * config type is "html".
      */
     HTML("html"),
-
+    
     /**
-     * config type is "yaml"
+     * config type is "yaml".
      */
     YAML("yaml");
-
+    
     String type;
-
+    
     ConfigType(String type) {
         this.type = type;
     }
-
+    
     public String getType() {
         return type;
     }

api/src/main/java/com/alibaba/nacos/api/config/PropertyChangeType.java

@@ -13,18 +13,25 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config;
 
 /**
- * Property Change Type
+ * Property Change Type.
  *
  * @author rushsky518
  */
 public enum PropertyChangeType {
-    /** add */
+    /**
+     * add.
+     */
     ADDED,
-    /** modified */
+    /**
+     * modified.
+     */
     MODIFIED,
-    /** deleted */
+    /**
+     * deleted.
+     */
     DELETED
 }

api/src/main/java/com/alibaba/nacos/api/config/annotation/NacosConfigListener.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.annotation;
 
 import com.alibaba.nacos.api.annotation.NacosProperties;
@@ -20,7 +21,11 @@ import com.alibaba.nacos.api.common.Constants;
 import com.alibaba.nacos.api.config.ConfigType;
 import com.alibaba.nacos.api.config.convert.NacosConfigConverter;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 import static com.alibaba.nacos.api.common.Constants.DEFAULT_GROUP;
 
@@ -34,42 +39,42 @@ import static com.alibaba.nacos.api.common.Constants.DEFAULT_GROUP;
 @Target(ElementType.METHOD)
 @Documented
 public @interface NacosConfigListener {
-
+    
     /**
-     * Nacos Group ID
+     * Nacos Group ID.
      *
      * @return default value {@link Constants#DEFAULT_GROUP};
      */
     String groupId() default DEFAULT_GROUP;
-
+    
     /**
-     * Nacos Data ID
+     * Nacos Data ID.
      *
      * @return required value.
      */
     String dataId();
-
+    
     /**
-     * Nacos Config type
+     * Nacos Config type.
      *
      * @return "properties"
      */
     ConfigType type() default ConfigType.PROPERTIES;
-
+    
     /**
      * Specify {@link NacosConfigConverter Nacos configuraion convertor} class to convert target type instance.
      *
      * @return The implementation class of {@link NacosConfigConverter}
      */
     Class<? extends NacosConfigConverter> converter() default NacosConfigConverter.class;
-
+    
     /**
      * The {@link NacosProperties} attribute, If not specified, it will use global Nacos Properties.
      *
      * @return the default value is {@link NacosProperties}
      */
     NacosProperties properties() default @NacosProperties;
-
+    
     /**
      * Maximum timeout value of execution in milliseconds, which is used to prevent long-time blocking execution
      * impacting others.
@@ -77,5 +82,5 @@ public @interface NacosConfigListener {
      * @return default value is 1000
      */
     long timeout() default 1000L;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/annotation/NacosConfigurationProperties.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.annotation;
 
 import com.alibaba.nacos.api.PropertyKeyConst;
@@ -20,7 +21,11 @@ import com.alibaba.nacos.api.annotation.NacosProperties;
 import com.alibaba.nacos.api.common.Constants;
 import com.alibaba.nacos.api.config.ConfigType;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 import static com.alibaba.nacos.api.common.Constants.DEFAULT_GROUP;
 
@@ -35,51 +40,49 @@ import static com.alibaba.nacos.api.common.Constants.DEFAULT_GROUP;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 public @interface NacosConfigurationProperties {
-
+    
     /**
-     * config prefix name
+     * config prefix name.
      *
      * @return default value is <code>""</code>
      */
     String prefix() default "";
-
+    
     /**
-     * Nacos Group ID
+     * Nacos Group ID.
      *
      * @return default value {@link Constants#DEFAULT_GROUP};
      */
     String groupId() default DEFAULT_GROUP;
-
+    
     /**
-     * Nacos Data ID
+     * Nacos Data ID.
      *
      * @return required value.
      */
     String dataId();
-
+    
     /**
-     * set config type is yaml
+     * set config type is yaml this method is deprecated, we support you use {@link #type()} to set config type.
-     * this method is deprecated, we support you use {@link #type()} to set config type
      *
      * @return default value <code>false</code>
      */
-    @Deprecated
+    @Deprecated boolean yaml() default false;
-    boolean yaml() default false;
+    
-
     /**
-     * config style
+     * config style.
      *
      * @return default value is {@link ConfigType#PROPERTIES}
      */
     ConfigType type() default ConfigType.PROPERTIES;
-
+    
     /**
      * It indicates the properties of current doBind bean is auto-refreshed when Nacos configuration is changed.
      *
      * @return default value is <code>false</code>
      */
     boolean autoRefreshed() default false;
-
+    
     /**
      * Flag to indicate that when binding to this object invalid fields should be ignored. Invalid means invalid
      * according to the binder that is used, and usually this means fields of the wrong type (or that cannot be coerced
@@ -88,14 +91,14 @@ public @interface NacosConfigurationProperties {
      * @return the flag value (default false)
      */
     boolean ignoreInvalidFields() default false;
-
+    
     /**
      * Flag to indicate that when binding to this object fields with periods in their names should be ignored.
      *
      * @return the flag value (default false)
      */
     boolean ignoreNestedProperties() default false;
-
+    
     /**
      * Flag to indicate that when binding to this object unknown fields should be ignored. An unknown field could be a
      * sign of a mistake in the Properties.
@@ -103,7 +106,7 @@ public @interface NacosConfigurationProperties {
      * @return the flag value (default true)
      */
     boolean ignoreUnknownFields() default true;
-
+    
     /**
      * Flag to indicate that an exception should be raised if a Validator is available and validation fails. If it is
      * set to false, validation errors will be swallowed. They will be logged, but not propagated to the caller.
@@ -111,12 +114,12 @@ public @interface NacosConfigurationProperties {
      * @return the flag value (default true)
      */
     boolean exceptionIfInvalid() default true;
-
+    
     /**
      * The {@link NacosProperties} attribute, If not specified, it will use global Nacos Properties.
      *
      * @return the default value is {@link NacosProperties}
      */
     NacosProperties properties() default @NacosProperties;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/annotation/NacosIgnore.java

@@ -13,9 +13,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.annotation;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 /**
  * An annotation for ignore field from annotated {@link NacosConfigurationProperties} Properties Object.
@@ -29,4 +34,5 @@ import java.lang.annotation.*;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 public @interface NacosIgnore {
+
 }

api/src/main/java/com/alibaba/nacos/api/config/annotation/NacosProperty.java

@@ -13,9 +13,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.annotation;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 /**
  * An annotation for Nacos Property name of  Nacos Configuration to bind a field from annotated {@link
@@ -30,12 +35,12 @@ import java.lang.annotation.*;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 public @interface NacosProperty {
-
+    
     /**
-     * The property name of Nacos Configuration to bind a field
+     * The property name of Nacos Configuration to bind a field.
      *
      * @return property name
      */
     String value();
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/annotation/NacosValue.java

@@ -13,12 +13,17 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.annotation;
 
-import java.lang.annotation.*;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 /**
- * Annotation which extends value to support auto-refresh
+ * Annotation which extends value to support auto-refresh.
  *
  * @author <a href="mailto:huangxiaoyu1018@gmail.com">hxy1991</a>
  * @since 0.2.0
@@ -27,19 +32,19 @@ import java.lang.annotation.*;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 public @interface NacosValue {
-
+    
     /**
      * The actual value expression: e.g. "#{systemProperties.myProp}".
      *
      * @return value expression
      */
     String value();
-
+    
     /**
      * It indicates that the currently bound property is auto-refreshed when Nacos configuration is changed.
      *
      * @return default value is <code>false</code>
      */
     boolean autoRefreshed() default false;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/convert/NacosConfigConverter.java

@@ -13,25 +13,26 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.convert;
 
 /**
- * Nacos Config Converter
+ * Nacos Config Converter.
  *
  * @param <T> the target type that wanted
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  * @since 0.2.0
  */
 public interface NacosConfigConverter<T> {
-
+    
     /**
-     * can convert to be target type or not
+     * can convert to be target type or not.
      *
      * @param targetType the type of target
      * @return If can , return <code>true</code>, or <code>false</code>
      */
     boolean canConvert(Class<T> targetType);
-
+    
     /**
      * convert the Naocs's config of type S to target type T.
      *
@@ -39,5 +40,5 @@ public interface NacosConfigConverter<T> {
      * @return the converted object, which must be an instance of T (potentially {@code null})
      */
     T convert(String config);
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/filter/IConfigContext.java

@@ -13,24 +13,26 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.filter;
 
 /**
- * Config Context Interface
+ * Config Context Interface.
  *
  * @author Nacos
  */
 public interface IConfigContext {
+    
     /**
-     * Get context param by key
+     * Get context param by key.
      *
-     * @param key
+     * @param key parameter key
      * @return context
      */
     Object getParameter(String key);
-
+    
     /**
-     * Set context param
+     * Set context param.
      *
      * @param key   key
      * @param value value

api/src/main/java/com/alibaba/nacos/api/config/filter/IConfigFilter.java

@@ -13,25 +13,27 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.filter;
 
 import com.alibaba.nacos.api.exception.NacosException;
 
 /**
- * Config Filter Interface
+ * Config Filter Interface.
  *
  * @author Nacos
  */
 public interface IConfigFilter {
+    
     /**
-     * Init
+     * Init.
      *
      * @param filterConfig Filter Config
      */
     void init(IFilterConfig filterConfig);
-
+    
     /**
-     * do filter
+     * do filter.
      *
      * @param request     request
      * @param response    response
@@ -40,24 +42,24 @@ public interface IConfigFilter {
      */
     void doFilter(IConfigRequest request, IConfigResponse response, IConfigFilterChain filterChain)
             throws NacosException;
-
+    
     /**
-     * deploy
+     * deploy.
      */
     void deploy();
-
+    
     /**
-     * Get order
+     * Get order.
      *
      * @return order number
      */
     int getOrder();
-
+    
     /**
-     * Get filterName
+     * Get filterName.
      *
      * @return filter name
      */
     String getFilterName();
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/filter/IConfigFilterChain.java

@@ -13,23 +13,25 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.filter;
 
 import com.alibaba.nacos.api.exception.NacosException;
 
 /**
- * Config Filter Chain Interface
+ * Config Filter Chain Interface.
  *
  * @author Nacos
  */
 public interface IConfigFilterChain {
+    
     /**
-     * Filter aciton
+     * Filter action.
      *
      * @param request  request
      * @param response response
      * @throws NacosException NacosException
      */
     void doFilter(IConfigRequest request, IConfigResponse response) throws NacosException;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/filter/IConfigRequest.java

@@ -13,27 +13,29 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.filter;
 
 /**
- * Config Request Interface
+ * Config Request Interface.
  *
  * @author Nacos
  */
 public interface IConfigRequest {
+    
     /**
-     * get param
+     * get param.
      *
      * @param key key
      * @return value
      */
     Object getParameter(String key);
-
+    
     /**
-     * get config context
+     * get config context.
      *
-     * @return
+     * @return {@link IConfigContext}
      */
     IConfigContext getConfigContext();
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/filter/IConfigResponse.java

@@ -13,27 +13,29 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.filter;
 
 /**
- * Config Response Interface
+ * Config Response Interface.
  *
  * @author Nacos
  */
 public interface IConfigResponse {
+    
     /**
-     * get param
+     * get param.
      *
      * @param key key
      * @return value
      */
     Object getParameter(String key);
-
+    
     /**
-     * Get config context
+     * Get config context.
      *
      * @return configContext
      */
     IConfigContext getConfigContext();
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/filter/IFilterConfig.java

@@ -13,28 +13,29 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.filter;
 
 /**
- * Filter Config Interface
+ * Filter Config Interface.
  *
  * @author Nacos
  */
 public interface IFilterConfig {
-
+    
     /**
-     * get filter name
+     * get filter name.
      *
-     * @return
+     * @return filter name
      */
     String getFilterName();
-
+    
     /**
-     * Get init param
+     * Get init param.
      *
-     * @param name
+     * @param name parameter name
      * @return param
      */
     Object getInitParameter(String name);
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/listener/AbstractListener.java

@@ -13,24 +13,25 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.listener;
 
 import java.util.concurrent.Executor;
 
 /**
- * Listener Adapter,use default notify thread
+ * Listener Adapter,use default notify thread.
  *
  * @author water.lyl
  */
 @SuppressWarnings("PMD.AbstractClassShouldStartWithAbstractNamingRule")
 public abstract class AbstractListener implements Listener {
-
+    
     /**
-     * Use default executor
+     * Use default executor.
      */
     @Override
     public Executor getExecutor() {
         return null;
     }
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/config/listener/AbstractSharedListener.java

@@ -13,38 +13,40 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.listener;
 
 import java.util.concurrent.Executor;
 
 /**
- * Shared Listener
+ * Shared Listener.
  *
  * @author Nacos
  */
 @SuppressWarnings("PMD.AbstractClassShouldStartWithAbstractNamingRule")
 public abstract class AbstractSharedListener implements Listener {
-
+    
     private volatile String dataId;
+    
     private volatile String group;
-
+    
     public final void fillContext(String dataId, String group) {
         this.dataId = dataId;
         this.group = group;
     }
-
+    
     @Override
     public final void receiveConfigInfo(String configInfo) {
         innerReceive(dataId, group, configInfo);
     }
-
+    
     @Override
     public Executor getExecutor() {
         return null;
     }
-
+    
     /**
-     * receive
+     * receive.
      *
      * @param dataId     data ID
      * @param group      group

api/src/main/java/com/alibaba/nacos/api/config/listener/ConfigChangeParser.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.listener;
 
 import com.alibaba.nacos.api.config.ConfigChangeItem;
@@ -21,25 +22,28 @@ import java.io.IOException;
 import java.util.Map;
 
 /**
- * ConfigChangeParser
+ * ConfigChangeParser.
  *
  * @author rushsky518
  */
 public interface ConfigChangeParser {
+    
     /**
-     * judge type
+     * Judge type.
-     * @param type
+     *
-     * @return
+     * @param type data type
+     * @return true if is responsible type, otherwise false
      */
     boolean isResponsibleFor(String type);
-
+    
     /**
-     * compare old and new data
+     * Compare old and new data.
-     * @param oldContent
+     *
-     * @param newContent
+     * @param oldContent old content
-     * @param type
+     * @param newContent new content
-     * @return
+     * @param type       data type
-     * @throws IOException
+     * @return key and change item map
+     * @throws IOException io exception
      */
     Map<String, ConfigChangeItem> doParse(String oldContent, String newContent, String type) throws IOException;
 }

api/src/main/java/com/alibaba/nacos/api/config/listener/Listener.java

@@ -13,26 +13,27 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.config.listener;
 
 import java.util.concurrent.Executor;
 
 /**
- * Listener for watch config
+ * Listener for watch config.
  *
  * @author Nacos
  */
 public interface Listener {
-
+    
     /**
-     * Get executor for execute this receive
+     * Get executor for execute this receive.
      *
      * @return Executor
      */
     Executor getExecutor();
-
+    
     /**
-     * Receive config info
+     * Receive config info.
      *
      * @param configInfo config info
      */

api/src/main/java/com/alibaba/nacos/api/exception/runtime/NacosDeserializationException.java

@@ -24,47 +24,43 @@ import java.lang.reflect.Type;
  * @author yangyi
  */
 public class NacosDeserializationException extends NacosRuntimeException {
-
+    
     public static final int ERROR_CODE = 101;
-
+    
     private static final long serialVersionUID = -2742350751684273728L;
-
+    
     private static final String DEFAULT_MSG = "Nacos deserialize failed. ";
-
+    
     private static final String MSG_FOR_SPECIFIED_CLASS = "Nacos deserialize for class [%s] failed. ";
-
+    
     private Class<?> targetClass;
-
+    
     public NacosDeserializationException() {
         super(ERROR_CODE);
     }
-
+    
     public NacosDeserializationException(Class<?> targetClass) {
         super(ERROR_CODE, String.format(MSG_FOR_SPECIFIED_CLASS, targetClass.getName()));
         this.targetClass = targetClass;
     }
-
+    
     public NacosDeserializationException(Type targetType) {
         super(ERROR_CODE, String.format(MSG_FOR_SPECIFIED_CLASS, targetType.toString()));
     }
-
+    
     public NacosDeserializationException(Throwable throwable) {
         super(ERROR_CODE, DEFAULT_MSG, throwable);
     }
-
+    
     public NacosDeserializationException(Class<?> targetClass, Throwable throwable) {
         super(ERROR_CODE, String.format(MSG_FOR_SPECIFIED_CLASS, targetClass.getName()), throwable);
         this.targetClass = targetClass;
     }
-
+    
     public NacosDeserializationException(Type targetType, Throwable throwable) {
         super(ERROR_CODE, String.format(MSG_FOR_SPECIFIED_CLASS, targetType.toString()), throwable);
     }
-
+    
-
-
-
-
     public Class<?> getTargetClass() {
         return targetClass;
     }

api/src/main/java/com/alibaba/nacos/api/exception/runtime/NacosRuntimeException.java

@@ -22,37 +22,37 @@ package com.alibaba.nacos.api.exception.runtime;
  * @author yangyi
  */
 public class NacosRuntimeException extends RuntimeException {
-
+    
     private static final long serialVersionUID = 3513491993982293262L;
-
+    
     public static final String ERROR_MESSAGE_FORMAT = "errCode: %d, errMsg: %s ";
-
+    
     private int errCode;
-
+    
     public NacosRuntimeException(int errCode) {
         super();
         this.errCode = errCode;
     }
-
+    
     public NacosRuntimeException(int errCode, String errMsg) {
         super(String.format(ERROR_MESSAGE_FORMAT, errCode, errMsg));
         this.errCode = errCode;
     }
-
+    
     public NacosRuntimeException(int errCode, Throwable throwable) {
         super(throwable);
         this.errCode = errCode;
     }
-
+    
     public NacosRuntimeException(int errCode, String errMsg, Throwable throwable) {
         super(String.format(ERROR_MESSAGE_FORMAT, errCode, errMsg), throwable);
         this.errCode = errCode;
     }
-
+    
     public int getErrCode() {
         return errCode;
     }
-
+    
     public void setErrCode(int errCode) {
         this.errCode = errCode;
     }

api/src/main/java/com/alibaba/nacos/api/exception/runtime/NacosSerializationException.java

@@ -22,35 +22,35 @@ package com.alibaba.nacos.api.exception.runtime;
  * @author yangyi
  */
 public class NacosSerializationException extends NacosRuntimeException {
-
+    
     public static final int ERROR_CODE = 100;
-
+    
     private static final long serialVersionUID = -4308536346316915612L;
-
+    
     private static final String DEFAULT_MSG = "Nacos serialize failed. ";
-
+    
     private static final String MSG_FOR_SPECIFIED_CLASS = "Nacos serialize for class [%s] failed. ";
-
+    
     private Class<?> serializedClass;
-
+    
     public NacosSerializationException() {
         super(ERROR_CODE);
     }
-
+    
     public NacosSerializationException(Class<?> serializedClass) {
         super(ERROR_CODE, String.format(MSG_FOR_SPECIFIED_CLASS, serializedClass.getName()));
         this.serializedClass = serializedClass;
     }
-
+    
     public NacosSerializationException(Throwable throwable) {
         super(ERROR_CODE, DEFAULT_MSG, throwable);
     }
-
+    
     public NacosSerializationException(Class<?> serializedClass, Throwable throwable) {
         super(ERROR_CODE, String.format(MSG_FOR_SPECIFIED_CLASS, serializedClass.getName()), throwable);
         this.serializedClass = serializedClass;
     }
-
+    
     public Class<?> getSerializedClass() {
         return serializedClass;
     }

api/src/main/java/com/alibaba/nacos/api/naming/CommonParams.java

@@ -13,25 +13,26 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming;
 
 /**
- * Common parameters for service discovery
+ * Common parameters for service discovery.
  *
  * @author nkorange
  * @since 1.0.0
  */
 public class CommonParams {
-
+    
     public static final String CODE = "code";
-
+    
     public static final String SERVICE_NAME = "serviceName";
-
+    
     public static final String CLUSTER_NAME = "clusterName";
-
+    
     public static final String NAMESPACE_ID = "namespaceId";
-
+    
     public static final String GROUP_NAME = "groupName";
-
+    
     public static final String LIGHT_BEAT_ENABLED = "lightBeatEnabled";
 }

api/src/main/java/com/alibaba/nacos/api/naming/NamingFactory.java

@@ -13,36 +13,51 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming;
 
+import com.alibaba.nacos.api.exception.NacosException;
+
 import java.lang.reflect.Constructor;
 import java.util.Properties;
 
-import com.alibaba.nacos.api.exception.NacosException;
-
 /**
- * Naming Factory
+ * Naming Factory.
  *
  * @author nkorange
  */
 public class NamingFactory {
-
+    
+    /**
+     * Create a new naming service.
+     *
+     * @param serverList server list
+     * @return new naming service
+     * @throws NacosException nacos exception
+     */
     public static NamingService createNamingService(String serverList) throws NacosException {
         try {
             Class<?> driverImplClass = Class.forName("com.alibaba.nacos.client.naming.NacosNamingService");
             Constructor constructor = driverImplClass.getConstructor(String.class);
-            NamingService vendorImpl = (NamingService)constructor.newInstance(serverList);
+            NamingService vendorImpl = (NamingService) constructor.newInstance(serverList);
             return vendorImpl;
         } catch (Throwable e) {
             throw new NacosException(NacosException.CLIENT_INVALID_PARAM, e);
         }
     }
-
+    
+    /**
+     * Create a new naming service.
+     *
+     * @param properties naming service properties
+     * @return new naming service
+     * @throws NacosException nacos exception
+     */
     public static NamingService createNamingService(Properties properties) throws NacosException {
         try {
             Class<?> driverImplClass = Class.forName("com.alibaba.nacos.client.naming.NacosNamingService");
             Constructor constructor = driverImplClass.getConstructor(Properties.class);
-            NamingService vendorImpl = (NamingService)constructor.newInstance(properties);
+            NamingService vendorImpl = (NamingService) constructor.newInstance(properties);
             return vendorImpl;
         } catch (Throwable e) {
             throw new NacosException(NacosException.CLIENT_INVALID_PARAM, e);

api/src/main/java/com/alibaba/nacos/api/naming/NamingMaintainFactory.java

@@ -22,31 +22,47 @@ import java.lang.reflect.Constructor;
 import java.util.Properties;
 
 /**
+ * Maintain service factory.
+ *
  * @author liaochuntao
  * @since 1.0.1
  */
 public class NamingMaintainFactory {
-
+    
+    /**
+     * create a new maintain service.
+     *
+     * @param serverList server list
+     * @return new maintain service
+     * @throws NacosException nacos exception
+     */
     public static NamingMaintainService createMaintainService(String serverList) throws NacosException {
         try {
             Class<?> driverImplClass = Class.forName("com.alibaba.nacos.client.naming.NacosNamingMaintainService");
             Constructor constructor = driverImplClass.getConstructor(String.class);
-            NamingMaintainService vendorImpl = (NamingMaintainService)constructor.newInstance(serverList);
+            NamingMaintainService vendorImpl = (NamingMaintainService) constructor.newInstance(serverList);
             return vendorImpl;
         } catch (Throwable e) {
             throw new NacosException(NacosException.CLIENT_INVALID_PARAM, e);
         }
     }
-
+    
+    /**
+     * create a new maintain service.
+     *
+     * @param properties properties
+     * @return new maintain service
+     * @throws NacosException nacos exception
+     */
     public static NamingMaintainService createMaintainService(Properties properties) throws NacosException {
         try {
             Class<?> driverImplClass = Class.forName("com.alibaba.nacos.client.naming.NacosNamingMaintainService");
             Constructor constructor = driverImplClass.getConstructor(Properties.class);
-            NamingMaintainService vendorImpl = (NamingMaintainService)constructor.newInstance(properties);
+            NamingMaintainService vendorImpl = (NamingMaintainService) constructor.newInstance(properties);
             return vendorImpl;
         } catch (Throwable e) {
             throw new NacosException(NacosException.CLIENT_INVALID_PARAM, e);
         }
     }
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/naming/NamingMaintainService.java

@@ -24,145 +24,147 @@ import com.alibaba.nacos.api.selector.AbstractSelector;
 import java.util.Map;
 
 /**
- * Operations related to Nacos
+ * Operations related to Nacos.
  *
  * @author liaochuntao
  * @since 1.0.1
  */
 public interface NamingMaintainService {
-
+    
     /**
-     * update instance info
+     * update instance info.
      *
-     * @param serviceName
+     * @param serviceName service name
-     * @param instance
+     * @param instance    instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void updateInstance(String serviceName, Instance instance) throws NacosException;
-
+    
     /**
-     * update instance info
+     * update instance info.
      *
-     * @param serviceName
+     * @param serviceName service name
-     * @param groupName
+     * @param groupName   group name
-     * @param instance
+     * @param instance    instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void updateInstance(String serviceName, String groupName, Instance instance) throws NacosException;
-
+    
     /**
-     * query service
+     * query service.
      *
-     * @param serviceName
+     * @param serviceName service name
-     * @return
+     * @return service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Service queryService(String serviceName) throws NacosException;
-
+    
     /**
-     * query service
+     * query service.
      *
-     * @param serviceName
+     * @param serviceName service name
-     * @param groupName
+     * @param groupName   group name
-     * @return
+     * @return service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Service queryService(String serviceName, String groupName) throws NacosException;
-
+    
     /**
-     * create service to Nacos
+     * create service to Nacos.
      *
      * @param serviceName name of service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void createService(String serviceName) throws NacosException;
-
+    
     /**
-     * create service to Nacos
+     * create service to Nacos.
      *
      * @param serviceName name of service
      * @param groupName   group of service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void createService(String serviceName, String groupName) throws NacosException;
-
+    
     /**
-     * create service to Nacos
+     * create service to Nacos.
      *
-     * @param serviceName           name of service
+     * @param serviceName      name of service
-     * @param groupName             group of service
+     * @param groupName        group of service
-     * @param protectThreshold      protectThreshold of service
+     * @param protectThreshold protectThreshold of service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void createService(String serviceName, String groupName, float protectThreshold) throws NacosException;
-
+    
     /**
-     * create service to Nacos
+     * create service to Nacos.
      *
-     * @param serviceName       name of service
+     * @param serviceName      name of service
-     * @param groupName         group of service
+     * @param groupName        group of service
-     * @param protectThreshold  protectThreshold of service
+     * @param protectThreshold protectThreshold of service
-     * @param expression        expression of selector
+     * @param expression       expression of selector
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    void createService(String serviceName, String groupName, float protectThreshold, String expression) throws NacosException;
+    void createService(String serviceName, String groupName, float protectThreshold, String expression)
-
+            throws NacosException;
+    
     /**
-     * create service to Nacos
+     * create service to Nacos.
      *
-     * @param service   name of service
+     * @param service  name of service
-     * @param selector  selector
+     * @param selector selector
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void createService(Service service, AbstractSelector selector) throws NacosException;
-
+    
     /**
-     * delete service from Nacos
+     * delete service from Nacos.
      *
      * @param serviceName name of service
      * @return if delete service success return true
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     boolean deleteService(String serviceName) throws NacosException;
-
+    
     /**
-     * delete service from Nacos
+     * delete service from Nacos.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @return if delete service success return true
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     boolean deleteService(String serviceName, String groupName) throws NacosException;
-
+    
     /**
-     * update service to Nacos
+     * update service to Nacos.
      *
-     * @param serviceName       name of service
+     * @param serviceName      name of service
-     * @param groupName         group of service
+     * @param groupName        group of service
-     * @param protectThreshold  protectThreshold of service
+     * @param protectThreshold protectThreshold of service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void updateService(String serviceName, String groupName, float protectThreshold) throws NacosException;
-
+    
     /**
-     * update service to Nacos
+     * update service to Nacos.
      *
-     * @param serviceName       name of service
+     * @param serviceName      name of service
-     * @param groupName         group of service
+     * @param groupName        group of service
-     * @param protectThreshold  protectThreshold of service
+     * @param protectThreshold protectThreshold of service
-     * @param metadata          metadata of service
+     * @param metadata         metadata of service
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    void updateService(String serviceName, String groupName, float protectThreshold, Map<String, String> metadata) throws NacosException;
+    void updateService(String serviceName, String groupName, float protectThreshold, Map<String, String> metadata)
-
+            throws NacosException;
+    
     /**
-     * update service to Nacos with selector
+     * update service to Nacos with selector.
      *
-     * @param service    {@link Service} pojo of service
+     * @param service  {@link Service} pojo of service
-     * @param selector   {@link AbstractSelector} pojo of selector
+     * @param selector {@link AbstractSelector} pojo of selector
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void updateService(Service service, AbstractSelector selector) throws NacosException;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/naming/NamingResponseCode.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming;
 
 import com.alibaba.nacos.api.common.ResponseCode;
@@ -20,16 +21,16 @@ import com.alibaba.nacos.api.common.ResponseCode;
 /**
  * Business response code of naming module
  *
- * Every code stays between 20001 to 29999.
+ * <p>Every code stays between 20001 to 29999.
  *
  * @author nkorange
  * @author 1.2.0
  */
 public class NamingResponseCode extends ResponseCode {
-
+    
     /**
-     * The requested resource is not found
+     * The requested resource is not found.
      */
     public static final int RESOURCE_NOT_FOUND = 20404;
-
+    
 }

api/src/main/java/com/alibaba/nacos/api/naming/NamingService.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming;
 
 import com.alibaba.nacos.api.exception.NacosException;
@@ -25,302 +26,309 @@ import com.alibaba.nacos.api.selector.AbstractSelector;
 import java.util.List;
 
 /**
- * Naming Service
+ * Naming Service.
  *
  * @author nkorange
  */
 public interface NamingService {
-
+    
     /**
-     * register a instance to service
+     * register a instance to service.
      *
      * @param serviceName name of service
      * @param ip          instance ip
      * @param port        instance port
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void registerInstance(String serviceName, String ip, int port) throws NacosException;
-
+    
     /**
-     * register a instance to service
+     * register a instance to service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param ip          instance ip
      * @param port        instance port
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void registerInstance(String serviceName, String groupName, String ip, int port) throws NacosException;
-
+    
     /**
-     * register a instance to service with specified cluster name
+     * register a instance to service with specified cluster name.
      *
      * @param serviceName name of service
      * @param ip          instance ip
      * @param port        instance port
      * @param clusterName instance cluster name
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void registerInstance(String serviceName, String ip, int port, String clusterName) throws NacosException;
-
+    
     /**
-     * register a instance to service with specified cluster name
+     * register a instance to service with specified cluster name.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param ip          instance ip
      * @param port        instance port
      * @param clusterName instance cluster name
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    void registerInstance(String serviceName, String groupName, String ip, int port, String clusterName) throws NacosException;
+    void registerInstance(String serviceName, String groupName, String ip, int port, String clusterName)
-
+            throws NacosException;
+    
     /**
-     * register a instance to service with specified instance properties
+     * register a instance to service with specified instance properties.
      *
      * @param serviceName name of service
      * @param instance    instance to register
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void registerInstance(String serviceName, Instance instance) throws NacosException;
-
+    
     /**
-     * register a instance to service with specified instance properties
+     * register a instance to service with specified instance properties.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param instance    instance to register
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void registerInstance(String serviceName, String groupName, Instance instance) throws NacosException;
-
+    
     /**
-     * deregister instance from a service
+     * deregister instance from a service.
      *
      * @param serviceName name of service
      * @param ip          instance ip
      * @param port        instance port
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void deregisterInstance(String serviceName, String ip, int port) throws NacosException;
-
+    
     /**
-     * deregister instance from a service
+     * deregister instance from a service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param ip          instance ip
      * @param port        instance port
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void deregisterInstance(String serviceName, String groupName, String ip, int port) throws NacosException;
-
+    
     /**
-     * deregister instance with specified cluster name from a service
+     * deregister instance with specified cluster name from a service.
      *
      * @param serviceName name of service
      * @param ip          instance ip
      * @param port        instance port
      * @param clusterName instance cluster name
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void deregisterInstance(String serviceName, String ip, int port, String clusterName) throws NacosException;
-
+    
     /**
-     * deregister instance with specified cluster name from a service
+     * deregister instance with specified cluster name from a service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param ip          instance ip
      * @param port        instance port
      * @param clusterName instance cluster name
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    void deregisterInstance(String serviceName, String groupName, String ip, int port, String clusterName) throws NacosException;
+    void deregisterInstance(String serviceName, String groupName, String ip, int port, String clusterName)
-
+            throws NacosException;
+    
     /**
-     * deregister instance with full instance information and default groupName
+     * deregister instance with full instance information and default groupName.
-     * @param serviceName
+     *
-     * @param instance
+     * @param serviceName name of service
-     * @throws NacosException
+     * @param instance    instance
+     * @throws NacosException nacos exception
      */
     void deregisterInstance(String serviceName, Instance instance) throws NacosException;
-
+    
     /**
-     * deregister instance with full instance information
+     * deregister instance with full instance information.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param instance    instance information
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void deregisterInstance(String serviceName, String groupName, Instance instance) throws NacosException;
-
+    
     /**
-     * get all instances of a service
+     * get all instances of a service.
      *
      * @param serviceName name of service
      * @return A list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName) throws NacosException;
-
+    
     /**
-     * get all instances of a service
+     * get all instances of a service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @return A list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName, String groupName) throws NacosException;
-
+    
     /**
-     * Get all instances of a service
+     * Get all instances of a service.
      *
      * @param serviceName name of service
      * @param subscribe   if subscribe the service
      * @return A list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName, boolean subscribe) throws NacosException;
-
+    
     /**
-     * Get all instances of a service
+     * Get all instances of a service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param subscribe   if subscribe the service
      * @return A list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName, String groupName, boolean subscribe) throws NacosException;
-
+    
     /**
-     * Get all instances within specified clusters of a service
+     * Get all instances within specified clusters of a service.
      *
      * @param serviceName name of service
      * @param clusters    list of cluster
      * @return A list of qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName, List<String> clusters) throws NacosException;
-
+    
     /**
-     * Get all instances within specified clusters of a service
+     * Get all instances within specified clusters of a service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    list of cluster
      * @return A list of qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName, String groupName, List<String> clusters) throws NacosException;
-
+    
     /**
-     * Get all instances within specified clusters of a service
+     * Get all instances within specified clusters of a service.
      *
      * @param serviceName name of service
      * @param clusters    list of cluster
      * @param subscribe   if subscribe the service
      * @return A list of qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> getAllInstances(String serviceName, List<String> clusters, boolean subscribe) throws NacosException;
-
+    
     /**
-     * Get all instances within specified clusters of a service
+     * Get all instances within specified clusters of a service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    list of cluster
      * @param subscribe   if subscribe the service
      * @return A list of qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    List<Instance> getAllInstances(String serviceName, String groupName, List<String> clusters, boolean subscribe) throws NacosException;
+    List<Instance> getAllInstances(String serviceName, String groupName, List<String> clusters, boolean subscribe)
-
+            throws NacosException;
+    
     /**
-     * Get qualified instances of service
+     * Get qualified instances of service.
      *
-     * @param serviceName name of service
+     * @param serviceName name of service.
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> selectInstances(String serviceName, boolean healthy) throws NacosException;
-
+    
     /**
-     * Get qualified instances of service
+     * Get qualified instances of service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> selectInstances(String serviceName, String groupName, boolean healthy) throws NacosException;
-
+    
     /**
-     * Get qualified instances of service
+     * Get qualified instances of service.
      *
      * @param serviceName name of service
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @param subscribe   if subscribe the service
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> selectInstances(String serviceName, boolean healthy, boolean subscribe) throws NacosException;
-
+    
     /**
-     * Get qualified instances of service
+     * Get qualified instances of service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @param subscribe   if subscribe the service
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    List<Instance> selectInstances(String serviceName, String groupName, boolean healthy, boolean subscribe) throws NacosException;
+    List<Instance> selectInstances(String serviceName, String groupName, boolean healthy, boolean subscribe)
-
+            throws NacosException;
+    
     /**
-     * Get qualified instances within specified clusters of service
+     * Get qualified instances within specified clusters of service.
      *
      * @param serviceName name of service
      * @param clusters    list of cluster
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<Instance> selectInstances(String serviceName, List<String> clusters, boolean healthy) throws NacosException;
-
+    
     /**
-     * Get qualified instances within specified clusters of service
+     * Get qualified instances within specified clusters of service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    list of cluster
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    List<Instance> selectInstances(String serviceName, String groupName, List<String> clusters, boolean healthy) throws NacosException;
+    List<Instance> selectInstances(String serviceName, String groupName, List<String> clusters, boolean healthy)
-
+            throws NacosException;
+    
     /**
-     * Get qualified instances within specified clusters of service
+     * Get qualified instances within specified clusters of service.
      *
      * @param serviceName name of service
      * @param clusters    list of cluster
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @param subscribe   if subscribe the service
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    List<Instance> selectInstances(String serviceName, List<String> clusters, boolean healthy, boolean subscribe) throws NacosException;
+    List<Instance> selectInstances(String serviceName, List<String> clusters, boolean healthy, boolean subscribe)
-
+            throws NacosException;
+    
     /**
-     * Get qualified instances within specified clusters of service
+     * Get qualified instances within specified clusters of service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
@@ -328,234 +336,241 @@ public interface NamingService {
      * @param healthy     a flag to indicate returning healthy or unhealthy instances
      * @param subscribe   if subscribe the service
      * @return A qualified list of instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    List<Instance> selectInstances(String serviceName, String groupName, List<String> clusters, boolean healthy, boolean subscribe) throws NacosException;
+    List<Instance> selectInstances(String serviceName, String groupName, List<String> clusters, boolean healthy,
-
+            boolean subscribe) throws NacosException;
+    
     /**
-     * Select one healthy instance of service using predefined load balance strategy
+     * Select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Instance selectOneHealthyInstance(String serviceName) throws NacosException;
-
+    
     /**
-     * Select one healthy instance of service using predefined load balance strategy
+     * Select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Instance selectOneHealthyInstance(String serviceName, String groupName) throws NacosException;
-
+    
     /**
-     * select one healthy instance of service using predefined load balance strategy
+     * select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param subscribe   if subscribe the service
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Instance selectOneHealthyInstance(String serviceName, boolean subscribe) throws NacosException;
-
+    
     /**
-     * select one healthy instance of service using predefined load balance strategy
+     * select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param subscribe   if subscribe the service
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Instance selectOneHealthyInstance(String serviceName, String groupName, boolean subscribe) throws NacosException;
-
+    
     /**
-     * Select one healthy instance of service using predefined load balance strategy
+     * Select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param clusters    a list of clusters should the instance belongs to
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     Instance selectOneHealthyInstance(String serviceName, List<String> clusters) throws NacosException;
-
+    
     /**
-     * Select one healthy instance of service using predefined load balance strategy
+     * Select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    a list of clusters should the instance belongs to
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    Instance selectOneHealthyInstance(String serviceName, String groupName, List<String> clusters) throws NacosException;
+    Instance selectOneHealthyInstance(String serviceName, String groupName, List<String> clusters)
-
+            throws NacosException;
+    
     /**
-     * Select one healthy instance of service using predefined load balance strategy
+     * Select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param clusters    a list of clusters should the instance belongs to
      * @param subscribe   if subscribe the service
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    Instance selectOneHealthyInstance(String serviceName, List<String> clusters, boolean subscribe) throws NacosException;
+    Instance selectOneHealthyInstance(String serviceName, List<String> clusters, boolean subscribe)
-
+            throws NacosException;
+    
     /**
-     * Select one healthy instance of service using predefined load balance strategy
+     * Select one healthy instance of service using predefined load balance strategy.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    a list of clusters should the instance belongs to
      * @param subscribe   if subscribe the service
      * @return qualified instance
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    Instance selectOneHealthyInstance(String serviceName, String groupName, List<String> clusters, boolean subscribe) throws NacosException;
+    Instance selectOneHealthyInstance(String serviceName, String groupName, List<String> clusters, boolean subscribe)
-
+            throws NacosException;
+    
     /**
-     * Subscribe service to receive events of instances alteration
+     * Subscribe service to receive events of instances alteration.
      *
      * @param serviceName name of service
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void subscribe(String serviceName, EventListener listener) throws NacosException;
-
+    
     /**
-     * Subscribe service to receive events of instances alteration
+     * Subscribe service to receive events of instances alteration.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void subscribe(String serviceName, String groupName, EventListener listener) throws NacosException;
-
+    
     /**
-     * Subscribe service to receive events of instances alteration
+     * Subscribe service to receive events of instances alteration.
      *
      * @param serviceName name of service
      * @param clusters    list of cluster
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void subscribe(String serviceName, List<String> clusters, EventListener listener) throws NacosException;
-
+    
     /**
-     * Subscribe service to receive events of instances alteration
+     * Subscribe service to receive events of instances alteration.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    list of cluster
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    void subscribe(String serviceName, String groupName, List<String> clusters, EventListener listener) throws NacosException;
+    void subscribe(String serviceName, String groupName, List<String> clusters, EventListener listener)
-
+            throws NacosException;
+    
     /**
-     * Unsubscribe event listener of service
+     * Unsubscribe event listener of service.
      *
      * @param serviceName name of service
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void unsubscribe(String serviceName, EventListener listener) throws NacosException;
-
+    
     /**
-     * unsubscribe event listener of service
+     * unsubscribe event listener of service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void unsubscribe(String serviceName, String groupName, EventListener listener) throws NacosException;
-
+    
     /**
-     * Unsubscribe event listener of service
+     * Unsubscribe event listener of service.
      *
      * @param serviceName name of service
      * @param clusters    list of cluster
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     void unsubscribe(String serviceName, List<String> clusters, EventListener listener) throws NacosException;
-
+    
     /**
-     * Unsubscribe event listener of service
+     * Unsubscribe event listener of service.
      *
      * @param serviceName name of service
      * @param groupName   group of service
      * @param clusters    list of cluster
      * @param listener    event listener
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    void unsubscribe(String serviceName, String groupName, List<String> clusters, EventListener listener) throws NacosException;
+    void unsubscribe(String serviceName, String groupName, List<String> clusters, EventListener listener)
-
+            throws NacosException;
+    
     /**
-     * Get all service names from server
+     * Get all service names from server.
      *
      * @param pageNo   page index
      * @param pageSize page size
      * @return list of service names
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     ListView<String> getServicesOfServer(int pageNo, int pageSize) throws NacosException;
-
+    
     /**
-     * Get all service names from server
+     * Get all service names from server.
      *
      * @param pageNo    page index
      * @param pageSize  page size
      * @param groupName group name
      * @return list of service names
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     ListView<String> getServicesOfServer(int pageNo, int pageSize, String groupName) throws NacosException;
-
+    
     /**
-     * Get all service names from server with selector
+     * Get all service names from server with selector.
      *
      * @param pageNo   page index
      * @param pageSize page size
      * @param selector selector to filter the resource
      * @return list of service names
-     * @throws NacosException
+     * @throws NacosException nacos exception
      * @since 0.7.0
      */
     ListView<String> getServicesOfServer(int pageNo, int pageSize, AbstractSelector selector) throws NacosException;
-
+    
     /**
-     * Get all service names from server with selector
+     * Get all service names from server with selector.
      *
      * @param pageNo    page index
      * @param pageSize  page size
      * @param groupName group name
      * @param selector  selector to filter the resource
      * @return list of service names
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
-    ListView<String> getServicesOfServer(int pageNo, int pageSize, String groupName, AbstractSelector selector) throws NacosException;
+    ListView<String> getServicesOfServer(int pageNo, int pageSize, String groupName, AbstractSelector selector)
-
+            throws NacosException;
+    
     /**
-     * Get all subscribed services of current client
+     * Get all subscribed services of current client.
      *
      * @return subscribed services
-     * @throws NacosException
+     * @throws NacosException nacos exception
      */
     List<ServiceInfo> getSubscribeServices() throws NacosException;
-
+    
     /**
-     * get server health status
+     * get server health status.
      *
      * @return is server healthy
      */
     String getServerStatus();
-
+    
     /**
      * Shutdown the resource service.
      *

api/src/main/java/com/alibaba/nacos/api/naming/PreservedMetadataKeys.java

@@ -13,26 +13,27 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming;
 
 /**
- * Some keys of metadata that are recognized by Nacos
+ * Some keys of metadata that are recognized by Nacos.
  *
  * @author nkorange
  * @since 1.0.0
  */
 public class PreservedMetadataKeys {
-
+    
     /**
      * The key to indicate the registry source of service instance, such as Dubbo, SpringCloud, etc.
      */
     public static final String REGISTER_SOURCE = "preserved.register.source";
-
+    
     public static final String HEART_BEAT_TIMEOUT = "preserved.heart.beat.timeout";
-
+    
     public static final String IP_DELETE_TIMEOUT = "preserved.ip.delete.timeout";
-
+    
     public static final String HEART_BEAT_INTERVAL = "preserved.heart.beat.interval";
-
+    
     public static final String INSTANCE_ID_GENERATOR = "preserved.instance.id.generator";
 }

api/src/main/java/com/alibaba/nacos/api/naming/listener/Event.java

@@ -13,12 +13,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.listener;
 
 /**
- * Event Interface
+ * Event Interface.
  *
  * @author nkorange
  */
 public interface Event {
+
 }

api/src/main/java/com/alibaba/nacos/api/naming/listener/EventListener.java

@@ -13,18 +13,20 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.listener;
 
 /**
- * Event Listener
+ * Event Listener.
  *
  * @author Nacos
  */
 public interface EventListener {
+    
     /**
-     * callback event
+     * callback event.
      *
-     * @param event
+     * @param event event
      */
     void onEvent(Event event);
 }

api/src/main/java/com/alibaba/nacos/api/naming/listener/NamingEvent.java

@@ -13,67 +13,68 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.nacos.api.naming.listener;
 
-import java.util.List;
+package com.alibaba.nacos.api.naming.listener;
 
 import com.alibaba.nacos.api.naming.pojo.Instance;
 
+import java.util.List;
+
 /**
- * Naming Event
+ * Naming Event.
  *
  * @author nkorange
  */
 public class NamingEvent implements Event {
-
+    
     private String serviceName;
-
+    
     private String groupName;
-
+    
     private String clusters;
-
+    
     private List<Instance> instances;
-
+    
     public NamingEvent(String serviceName, List<Instance> instances) {
         this.serviceName = serviceName;
         this.instances = instances;
     }
-
+    
     public NamingEvent(String serviceName, String groupName, String clusters, List<Instance> instances) {
         this.serviceName = serviceName;
         this.groupName = groupName;
         this.clusters = clusters;
         this.instances = instances;
     }
-
+    
     public String getServiceName() {
         return serviceName;
     }
-
+    
     public void setServiceName(String serviceName) {
         this.serviceName = serviceName;
     }
-
+    
     public List<Instance> getInstances() {
         return instances;
     }
-
+    
     public void setInstances(List<Instance> instances) {
         this.instances = instances;
     }
-
+    
     public String getGroupName() {
         return groupName;
     }
-
+    
     public void setGroupName(String groupName) {
         this.groupName = groupName;
     }
-
+    
     public String getClusters() {
         return clusters;
     }
-
+    
     public void setClusters(String clusters) {
         this.clusters = clusters;
     }

api/src/main/java/com/alibaba/nacos/api/naming/pojo/Cluster.java

@@ -13,113 +13,118 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.nacos.api.naming.pojo;
 
-import java.util.HashMap;
+package com.alibaba.nacos.api.naming.pojo;
-import java.util.Map;
 
 import com.alibaba.nacos.api.naming.pojo.healthcheck.AbstractHealthChecker;
 import com.alibaba.nacos.api.naming.pojo.healthcheck.impl.Tcp;
 
+import java.util.HashMap;
+import java.util.Map;
+
 /**
- * Cluster
+ * Cluster.
+ *
+ * <p>The class will be serialized to json, and there are some variables and method can't use Camel naming rule for
+ * compatibility
  *
  * @author nkorange
  */
+@SuppressWarnings("checkstyle:abbreviationaswordinname")
 public class Cluster {
-
+    
     /**
-     * Name of belonging service
+     * Name of belonging service.
      */
     private String serviceName;
-
+    
     /**
-     * Name of cluster
+     * Name of cluster.
      */
     private String name;
-
+    
     /**
-     * Health check config of this cluster
+     * Health check config of this cluster.
      */
     private AbstractHealthChecker healthChecker = new Tcp();
-
+    
     /**
      * Default registered port for instances in this cluster.
      */
     private int defaultPort = 80;
-
+    
     /**
      * Default health check port of instances in this cluster.
      */
     private int defaultCheckPort = 80;
-
+    
     /**
      * Whether or not use instance port to do health check.
      */
     private boolean useIPPort4Check = true;
-
+    
     private Map<String, String> metadata = new HashMap<String, String>();
-
+    
     public Cluster() {
-
+    
     }
-
+    
     public Cluster(String clusterName) {
         this.name = clusterName;
     }
-
+    
     public String getServiceName() {
         return serviceName;
     }
-
+    
     public void setServiceName(String serviceName) {
         this.serviceName = serviceName;
     }
-
+    
     public String getName() {
         return name;
     }
-
+    
     public void setName(String name) {
         this.name = name;
     }
-
+    
     public AbstractHealthChecker getHealthChecker() {
         return healthChecker;
     }
-
+    
     public void setHealthChecker(AbstractHealthChecker healthChecker) {
         this.healthChecker = healthChecker;
     }
-
+    
     public int getDefaultPort() {
         return defaultPort;
     }
-
+    
     public void setDefaultPort(int defaultPort) {
         this.defaultPort = defaultPort;
     }
-
+    
     public int getDefaultCheckPort() {
         return defaultCheckPort;
     }
-
+    
     public void setDefaultCheckPort(int defaultCheckPort) {
         this.defaultCheckPort = defaultCheckPort;
     }
-
+    
     public boolean isUseIPPort4Check() {
         return useIPPort4Check;
     }
-
+    
     public void setUseIPPort4Check(boolean useIPPort4Check) {
         this.useIPPort4Check = useIPPort4Check;
     }
-
+    
     public Map<String, String> getMetadata() {
         return metadata;
     }
-
+    
     public void setMetadata(Map<String, String> metadata) {
         this.metadata = metadata;
     }

api/src/main/java/com/alibaba/nacos/api/naming/pojo/Instance.java

@@ -182,10 +182,10 @@ public class Instance {
     
     @Override
     public String toString() {
-        return "Instance{" + "instanceId='" + instanceId + '\'' + ", ip='" + ip + '\'' + ", port=" + port
+        return "Instance{" + "instanceId='" + instanceId + '\'' + ", ip='" + ip + '\'' + ", port=" + port + ", weight="
-                + ", weight=" + weight + ", healthy=" + healthy + ", enabled=" + enabled + ", ephemeral="
+                + weight + ", healthy=" + healthy + ", enabled=" + enabled + ", ephemeral=" + ephemeral
-                + ephemeral + ", clusterName='" + clusterName + '\'' + ", serviceName='" + serviceName
+                + ", clusterName='" + clusterName + '\'' + ", serviceName='" + serviceName + '\'' + ", metadata="
-                + '\'' + ", metadata=" + metadata + '}';
+                + metadata + '}';
     }
     
     public String toInetAddr() {

api/src/main/java/com/alibaba/nacos/api/naming/pojo/ListView.java

@@ -13,41 +13,40 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.pojo;
 
 import java.util.List;
 
 /**
- * ListView
+ * ListView.
  *
  * @author nkorange
  */
 public class ListView<T> {
-
+    
     private List<T> data;
+    
     private int count;
-
+    
     public List<T> getData() {
         return data;
     }
-
+    
     public void setData(List<T> data) {
         this.data = data;
     }
-
+    
     public int getCount() {
         return count;
     }
-
+    
     public void setCount(int count) {
         this.count = count;
     }
-
+    
     @Override
     public String toString() {
-        return "ListView{" +
+        return "ListView{" + "data=" + data + ", count=" + count + '}';
-            "data=" + data +
-            ", count=" + count +
-            '}';
     }
 }

api/src/main/java/com/alibaba/nacos/api/naming/pojo/Service.java

@@ -13,103 +13,100 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.pojo;
 
 import java.util.HashMap;
 import java.util.Map;
 
 /**
- * Service of Nacos
+ * Service of Nacos.
- * <p>
+ *
- * We introduce a 'service --> cluster --> instance' model, in which service stores a list of clusters,
+ * <p>We introduce a 'service --> cluster --> instance' model, in which service stores a list of clusters, which contains a
- * which contains a list of instances.
+ * list of instances.
- * <p>
+ *
- * Typically we put some unique properties between instances to service level.
+ * <p>Typically we put some unique properties between instances to service level.
  *
  * @author nkorange
  */
 public class Service {
+    
     /**
-     * service name
+     * service name.
      */
     private String name;
-
+    
     /**
-     * protect threshold
+     * protect threshold.
      */
     private float protectThreshold = 0.0F;
-
+    
     /**
-     * application name of this service
+     * application name of this service.
      */
     private String appName;
-
+    
     /**
      * Service group to classify services into different sets.
      */
     private String groupName;
-
+    
     private Map<String, String> metadata = new HashMap<String, String>();
-
+    
     public Service() {
     }
-
+    
     public Service(String name) {
         this.name = name;
     }
-
+    
     public String getName() {
         return name;
     }
-
+    
     public void setName(String name) {
         this.name = name;
     }
-
+    
     public float getProtectThreshold() {
         return protectThreshold;
     }
-
+    
     public void setProtectThreshold(float protectThreshold) {
         this.protectThreshold = protectThreshold;
     }
-
+    
     public String getAppName() {
         return appName;
     }
-
+    
     public void setAppName(String appName) {
         this.appName = appName;
     }
-
+    
     public String getGroupName() {
         return groupName;
     }
-
+    
     public void setGroupName(String groupName) {
         this.groupName = groupName;
     }
-
+    
     public Map<String, String> getMetadata() {
         return metadata;
     }
-
+    
     public void setMetadata(Map<String, String> metadata) {
         this.metadata = metadata;
     }
-
+    
     public void addMetadata(String key, String value) {
         this.metadata.put(key, value);
     }
-
+    
     @Override
     public String toString() {
-        return "Service{" +
+        return "Service{" + "name='" + name + '\'' + ", protectThreshold=" + protectThreshold + ", appName='" + appName
-            "name='" + name + '\'' +
+                + '\'' + ", groupName='" + groupName + '\'' + ", metadata=" + metadata + '}';
-            ", protectThreshold=" + protectThreshold +
-            ", appName='" + appName + '\'' +
-            ", groupName='" + groupName + '\'' +
-            ", metadata=" + metadata +
-            '}';
     }
 }

api/src/main/java/com/alibaba/nacos/api/naming/pojo/ServiceInfo.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.pojo;
 
 import com.alibaba.nacos.api.common.Constants;
@@ -27,158 +28,173 @@ import java.util.Collection;
 import java.util.List;
 
 /**
- * ServiceInfo
+ * ServiceInfo.
  *
  * @author nkorange
  */
 @JsonInclude(Include.NON_NULL)
 public class ServiceInfo {
-
+    
     @JsonIgnore
     private String jsonFromServer = EMPTY;
-
+    
     public static final String SPLITER = "@@";
-
+    
     private String name;
-
+    
     private String groupName;
-
+    
     private String clusters;
-
+    
     private long cacheMillis = 1000L;
-
+    
     private List<Instance> hosts = new ArrayList<Instance>();
-
+    
     private long lastRefTime = 0L;
-
+    
     private String checksum = "";
-
+    
     private volatile boolean allIPs = false;
-
+    
     public ServiceInfo() {
     }
-
+    
     public boolean isAllIPs() {
         return allIPs;
     }
-
+    
     public void setAllIPs(boolean allIPs) {
         this.allIPs = allIPs;
     }
-
+    
     public ServiceInfo(String key) {
-
+        
         int maxIndex = 2;
         int clusterIndex = 1;
         int serviceNameIndex = 0;
-
+        
         String[] keys = key.split(Constants.SERVICE_INFO_SPLITER);
         if (keys.length >= maxIndex) {
             this.name = keys[serviceNameIndex];
             this.clusters = keys[clusterIndex];
         }
-
+        
         this.name = keys[0];
     }
-
+    
     public ServiceInfo(String name, String clusters) {
         this.name = name;
         this.clusters = clusters;
     }
-
+    
     public int ipCount() {
         return hosts.size();
     }
-
+    
     public boolean expired() {
         return System.currentTimeMillis() - lastRefTime > cacheMillis;
     }
-
+    
     public void setHosts(List<Instance> hosts) {
         this.hosts = hosts;
     }
-
+    
     public boolean isValid() {
         return hosts != null;
     }
-
+    
     public String getName() {
         return name;
     }
-
+    
     public void setName(String name) {
         this.name = name;
     }
-
+    
     public String getGroupName() {
         return groupName;
     }
-
+    
     public void setGroupName(String groupName) {
         this.groupName = groupName;
     }
-
+    
     public void setLastRefTime(long lastRefTime) {
         this.lastRefTime = lastRefTime;
     }
-
+    
     public long getLastRefTime() {
         return lastRefTime;
     }
-
+    
     public String getClusters() {
         return clusters;
     }
-
+    
     public void setClusters(String clusters) {
         this.clusters = clusters;
     }
-
+    
     public long getCacheMillis() {
         return cacheMillis;
     }
-
+    
     public void setCacheMillis(long cacheMillis) {
         this.cacheMillis = cacheMillis;
     }
-
+    
     public List<Instance> getHosts() {
         return new ArrayList<Instance>(hosts);
     }
-
+    
+    /**
+     * Judge whether service info is validate.
+     *
+     * @return true if validate, otherwise false
+     */
     public boolean validate() {
         if (isAllIPs()) {
             return true;
         }
-
+        
         List<Instance> validHosts = new ArrayList<Instance>();
         for (Instance host : hosts) {
             if (!host.isHealthy()) {
                 continue;
             }
-
+            
             for (int i = 0; i < host.getWeight(); i++) {
                 validHosts.add(host);
             }
         }
-
+        
         return true;
     }
-
+    
     @JsonIgnore
     public String getJsonFromServer() {
         return jsonFromServer;
     }
-
+    
     public void setJsonFromServer(String jsonFromServer) {
         this.jsonFromServer = jsonFromServer;
     }
-
+    
     @JsonIgnore
     public String getKey() {
         return getKey(name, clusters);
     }
-
+    
+    @JsonIgnore
+    public static String getKey(String name, String clusters) {
+        
+        if (!isEmpty(clusters)) {
+            return name + Constants.SERVICE_INFO_SPLITER + clusters;
+        }
+        
+        return name;
+    }
+    
     @JsonIgnore
     public String getKeyEncoded() {
         try {
@@ -187,12 +203,18 @@ public class ServiceInfo {
             return getKey();
         }
     }
-
+    
+    /**
+     * Get {@link ServiceInfo} from key.
+     *
+     * @param key key of service info
+     * @return new service info
+     */
     public static ServiceInfo fromKey(String key) {
         ServiceInfo serviceInfo = new ServiceInfo();
         int maxSegCount = 3;
         String[] segs = key.split(Constants.SERVICE_INFO_SPLITER);
-        if (segs.length == maxSegCount -1) {
+        if (segs.length == maxSegCount - 1) {
             serviceInfo.setGroupName(segs[0]);
             serviceInfo.setName(segs[1]);
         } else if (segs.length == maxSegCount) {
@@ -202,43 +224,33 @@ public class ServiceInfo {
         }
         return serviceInfo;
     }
-
+    
-    @JsonIgnore
-    public static String getKey(String name, String clusters) {
-
-        if (!isEmpty(clusters)) {
-            return name + Constants.SERVICE_INFO_SPLITER + clusters;
-        }
-
-        return name;
-    }
-
     @Override
     public String toString() {
         return getKey();
     }
-
+    
     public String getChecksum() {
         return checksum;
     }
-
+    
     public void setChecksum(String checksum) {
         this.checksum = checksum;
     }
-
+    
     private static boolean isEmpty(String str) {
         return str == null || str.length() == 0;
     }
-
+    
-    private static boolean strEquals(String str1, String str2) {
-        return str1 == null ? str2 == null : str1.equals(str2);
-    }
-
     private static boolean isEmpty(Collection coll) {
         return (coll == null || coll.isEmpty());
     }
-
+    
+    private static boolean strEquals(String str1, String str2) {
+        return str1 == null ? str2 == null : str1.equals(str2);
+    }
+    
     private static final String EMPTY = "";
-
+    
     private static final String ALL_IPS = "000--00-ALL_IPS--00--000";
 }

api/src/main/java/com/alibaba/nacos/api/naming/pojo/healthcheck/AbstractHealthChecker.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.pojo.healthcheck;
 
 import com.alibaba.nacos.api.naming.pojo.healthcheck.AbstractHealthChecker.None;
@@ -25,28 +26,27 @@ import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonTypeInfo.Id;
 
 /**
+ * Abstract health checker.
+ *
  * @author nkorange
  */
-
 @JsonTypeInfo(use = Id.NAME, property = "type", defaultImpl = None.class)
-@JsonSubTypes({
+@JsonSubTypes({@JsonSubTypes.Type(name = Http.TYPE, value = Http.class),
-    @JsonSubTypes.Type(name = Http.TYPE, value = Http.class),
+        @JsonSubTypes.Type(name = Mysql.TYPE, value = Mysql.class),
-    @JsonSubTypes.Type(name = Mysql.TYPE, value = Mysql.class),
+        @JsonSubTypes.Type(name = Tcp.TYPE, value = Tcp.class)})
-    @JsonSubTypes.Type(name = Tcp.TYPE, value = Tcp.class)
-})
 public abstract class AbstractHealthChecker implements Cloneable {
-
+    
     @JsonIgnore
     protected final String type;
-
+    
     protected AbstractHealthChecker(String type) {
         this.type = type;
     }
-
+    
     public String getType() {
         return type;
     }
-
+    
     /**
      * Clone all fields of this instance to another one.
      *
@@ -55,18 +55,18 @@ public abstract class AbstractHealthChecker implements Cloneable {
      */
     @Override
     public abstract AbstractHealthChecker clone() throws CloneNotSupportedException;
-
+    
     /**
      * Default implementation of Health checker.
      */
     public static class None extends AbstractHealthChecker {
-
+        
         public static final String TYPE = "NONE";
-
+        
         public None() {
             super(TYPE);
         }
-
+        
         @Override
         public AbstractHealthChecker clone() throws CloneNotSupportedException {
             return new None();

api/src/main/java/com/alibaba/nacos/api/naming/pojo/healthcheck/HealthCheckType.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.naming.pojo.healthcheck;
 
 import com.alibaba.nacos.api.naming.pojo.healthcheck.impl.Http;
@@ -25,57 +26,75 @@ import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
+ * Health check type.
+ *
  * @author nkorange
  */
 public enum HealthCheckType {
     /**
-     * TCP type
+     * TCP type.
      */
     TCP(Tcp.class),
     /**
-     * HTTP type
+     * HTTP type.
      */
     HTTP(Http.class),
     /**
-     * MySQL type
+     * MySQL type.
      */
     MYSQL(Mysql.class),
     /**
-     * No check
+     * No check.
      */
     NONE(AbstractHealthChecker.None.class);
-
+    
     private final Class<? extends AbstractHealthChecker> healthCheckerClass;
-
+    
+    /**
+     * In JDK 1.6, the map need full class for general. So ignore check style.
+     */
+    @SuppressWarnings("checkstyle:linelength")
     private static final Map<String, Class<? extends AbstractHealthChecker>> EXTEND = new ConcurrentHashMap<String, Class<? extends AbstractHealthChecker>>();
-
+    
     HealthCheckType(Class<? extends AbstractHealthChecker> healthCheckerClass) {
         this.healthCheckerClass = healthCheckerClass;
     }
-
+    
-    public static void registerHealthChecker(String type, Class<? extends AbstractHealthChecker> healthCheckerClass){
+    /**
+     * Register extend health checker.
+     *
+     * @param type               type name of extend health checker
+     * @param healthCheckerClass class of extend health checker
+     */
+    public static void registerHealthChecker(String type, Class<? extends AbstractHealthChecker> healthCheckerClass) {
         if (!EXTEND.containsKey(type)) {
             EXTEND.put(type, healthCheckerClass);
             HealthCheckerFactory.registerSubType(healthCheckerClass, type);
         }
     }
-
+    
-    public static Class<? extends AbstractHealthChecker> ofHealthCheckerClass(String type){
+    /**
+     * Get health checker class from type.
+     *
+     * @param type type name of extend health checker
+     * @return registered class if have, otherwise default class
+     */
+    public static Class<? extends AbstractHealthChecker> ofHealthCheckerClass(String type) {
         HealthCheckType enumType;
         try {
             enumType = valueOf(type);
-        }catch (Exception e){
+        } catch (Exception e) {
             return EXTEND.get(type);
         }
         return enumType.healthCheckerClass;
     }
-
+    
-    public static List<Class<? extends AbstractHealthChecker>> getLoadedHealthCheckerClasses(){
+    public static List<Class<? extends AbstractHealthChecker>> getLoadedHealthCheckerClasses() {
         List<Class<? extends AbstractHealthChecker>> all = new ArrayList<Class<? extends AbstractHealthChecker>>();
-        for(HealthCheckType type : values()){
+        for (HealthCheckType type : values()) {
             all.add(type.healthCheckerClass);
         }
-        for(Map.Entry<String, Class<? extends AbstractHealthChecker>> entry : EXTEND.entrySet()){
+        for (Map.Entry<String, Class<? extends AbstractHealthChecker>> entry : EXTEND.entrySet()) {
             all.add(entry.getValue());
         }
         return all;

api/src/main/java/com/alibaba/nacos/api/naming/pojo/healthcheck/HealthCheckerFactory.java

@@ -16,27 +16,27 @@
 
 package com.alibaba.nacos.api.naming.pojo.healthcheck;
 
-import java.io.IOException;
-
 import com.alibaba.nacos.api.naming.pojo.healthcheck.AbstractHealthChecker.None;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.jsontype.NamedType;
 
+import java.io.IOException;
+
 /**
  * health checker factory.
  *
  * @author yangyi
  */
 public class HealthCheckerFactory {
-
+    
     private static final ObjectMapper MAPPER = new ObjectMapper();
-
+    
     static {
         MAPPER.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
     }
-
+    
     /**
      * Register new sub type of health checker to factory for serialize and deserialize.
      *
@@ -45,17 +45,18 @@ public class HealthCheckerFactory {
     public static void registerSubType(AbstractHealthChecker extendHealthChecker) {
         registerSubType(extendHealthChecker.getClass(), extendHealthChecker.getType());
     }
-
+    
     /**
      * Register new sub type of health checker to factory for serialize and deserialize.
      *
      * @param extendHealthCheckerClass extend health checker
-     * @param typeName typeName of health checker
+     * @param typeName                 typeName of health checker
      */
-    public static void registerSubType(Class<? extends AbstractHealthChecker> extendHealthCheckerClass, String typeName) {
+    public static void registerSubType(Class<? extends AbstractHealthChecker> extendHealthCheckerClass,
+            String typeName) {
         MAPPER.registerSubtypes(new NamedType(extendHealthCheckerClass, typeName));
     }
-
+    
     /**
      * Create default {@link None} health checker.
      *
@@ -64,7 +65,7 @@ public class HealthCheckerFactory {
     public static None createNoneHealthChecker() {
         return new None();
     }
-
+    
     /**
      * Deserialize and create a instance of health checker.
      *
@@ -79,9 +80,9 @@ public class HealthCheckerFactory {
             throw new RuntimeException("Deserialize health checker from json failed", e);
         }
     }
-
+    
     /**
-     * Serialize a instance of health checker to json
+     * Serialize a instance of health checker to json.
      *
      * @param healthChecker health checker instance
      * @return son string after serializing

api/src/main/java/com/alibaba/nacos/api/naming/pojo/healthcheck/impl/Tcp.java

@@ -25,23 +25,23 @@ import com.google.common.base.Objects;
  * @author yangyi
  */
 public class Tcp extends AbstractHealthChecker {
-
+    
     public static final String TYPE = "TCP";
-
+    
     public Tcp() {
         super(TYPE);
     }
-
+    
     @Override
     public int hashCode() {
         return Objects.hashCode(TYPE);
     }
-
+    
     @Override
     public boolean equals(Object obj) {
         return obj instanceof Tcp;
     }
-
+    
     @Override
     public Tcp clone() throws CloneNotSupportedException {
         return new Tcp();

api/src/main/java/com/alibaba/nacos/api/selector/AbstractSelector.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.selector;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
@@ -20,24 +21,24 @@ import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonTypeInfo.Id;
 
 /**
- * Abstract selector that only contains a type
+ * Abstract selector that only contains a type.
  *
  * @author nkorange
  * @since 0.7.0
  */
 @JsonTypeInfo(use = Id.NAME, property = "type", defaultImpl = NoneSelector.class)
 public abstract class AbstractSelector {
-
+    
     /**
      * The type of this selector, each child class should announce its own unique type.
      */
     @JsonIgnore
     private final String type;
-
+    
     protected AbstractSelector(String type) {
         this.type = type;
     }
-
+    
     public String getType() {
         return type;
     }

api/src/main/java/com/alibaba/nacos/api/selector/ExpressionSelector.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.selector;
 
 /**
@@ -22,20 +23,20 @@ package com.alibaba.nacos.api.selector;
  * @since 0.7.0
  */
 public class ExpressionSelector extends AbstractSelector {
-
+    
     /**
      * Label expression of this selector.
      */
     private String expression;
-
+    
     public ExpressionSelector() {
         super(SelectorType.label.name());
     }
-
+    
     public String getExpression() {
         return expression;
     }
-
+    
     public void setExpression(String expression) {
         this.expression = expression;
     }

api/src/main/java/com/alibaba/nacos/api/selector/NoneSelector.java

@@ -17,11 +17,13 @@
 package com.alibaba.nacos.api.selector;
 
 /**
+ * None selector.
+ *
  * @author liaochuntao
  * @since 1.0.1
  */
 public class NoneSelector extends AbstractSelector {
-
+    
     public NoneSelector() {
         super(SelectorType.none.name());
     }

api/src/main/java/com/alibaba/nacos/api/selector/SelectorType.java

@@ -13,25 +13,26 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.selector;
 
 /**
- * The types of selector accepted by Nacos
+ * The types of selector accepted by Nacos.
  *
  * @author nkorange
  * @since 0.7.0
  */
 public enum SelectorType {
     /**
-     * not match any type
+     * not match any type.
      */
     unknown,
     /**
-     * not filter out any entity
+     * not filter out any entity.
      */
     none,
     /**
-     * select by label
+     * select by label.
      */
     label
 }

api/src/main/resources/application.properties

@@ -13,5 +13,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-
 version=${project.version}

api/src/test/java/com/alibaba/nacos/api/annotation/NacosPropertiesTest.java

@@ -13,22 +13,24 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.nacos.api.annotation;
 
 import org.junit.Assert;
 import org.junit.Test;
 import org.springframework.mock.env.MockEnvironment;
 
-import static com.alibaba.nacos.api.annotation.NacosProperties.*;
+import static com.alibaba.nacos.api.annotation.NacosProperties.ACCESS_KEY_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.CLUSTER_NAME_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.CONTEXT_PATH_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.ENCODE_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.ENDPOINT_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.NAMESPACE_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.SECRET_KEY_PLACEHOLDER;
+import static com.alibaba.nacos.api.annotation.NacosProperties.SERVER_ADDR_PLACEHOLDER;
 
-/**
- * {@link NacosProperties} Test
- *
- * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
- * @since 0.2.1
- */
 public class NacosPropertiesTest {
-
+    
     @Test
     public void testPlaceholders() {
         Assert.assertEquals("${nacos.endpoint:}", ENDPOINT_PLACEHOLDER);
@@ -40,43 +42,44 @@ public class NacosPropertiesTest {
         Assert.assertEquals("${nacos.cluster-name:}", CLUSTER_NAME_PLACEHOLDER);
         Assert.assertEquals("${nacos.encode:UTF-8}", ENCODE_PLACEHOLDER);
     }
-
+    
     @Test
     public void testResolvePlaceholders() {
         testResolvePlaceholder(ENDPOINT_PLACEHOLDER, "nacos.endpoint", "test-value", "test-value");
         testResolvePlaceholder(ENDPOINT_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(NAMESPACE_PLACEHOLDER, "nacos.namespace", "test-value", "test-value");
         testResolvePlaceholder(NAMESPACE_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(ACCESS_KEY_PLACEHOLDER, "nacos.access-key", "test-value", "test-value");
         testResolvePlaceholder(ACCESS_KEY_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(SECRET_KEY_PLACEHOLDER, "nacos.secret-key", "test-value", "test-value");
         testResolvePlaceholder(SECRET_KEY_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(SERVER_ADDR_PLACEHOLDER, "nacos.server-addr", "test-value", "test-value");
         testResolvePlaceholder(SERVER_ADDR_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(CONTEXT_PATH_PLACEHOLDER, "nacos.context-path", "test-value", "test-value");
         testResolvePlaceholder(CONTEXT_PATH_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(CLUSTER_NAME_PLACEHOLDER, "nacos.cluster-name", "test-value", "test-value");
         testResolvePlaceholder(CLUSTER_NAME_PLACEHOLDER, "", "test-value", "");
-
+        
         testResolvePlaceholder(ENCODE_PLACEHOLDER, "nacos.encode", "test-value", "test-value");
         testResolvePlaceholder(ENCODE_PLACEHOLDER, "", "test-value", "UTF-8");
     }
-
+    
-    private void testResolvePlaceholder(String placeholder, String propertyName, String propertyValue, String expectValue) {
+    private void testResolvePlaceholder(String placeholder, String propertyName, String propertyValue,
+            String expectValue) {
         MockEnvironment environment = new MockEnvironment();
         environment.setProperty(propertyName, propertyValue);
         String resolvedValue = environment.resolvePlaceholders(placeholder);
         Assert.assertEquals(expectValue, resolvedValue);
     }
-
+    
     @Test
     public void testSort() {
-
+    
     }
 }

api/src/test/java/com/alibaba/nacos/api/naming/pojo/ServiceInfoTest.java

@@ -21,6 +21,7 @@ import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.Before;
 import org.junit.Test;
+
 import java.io.IOException;
 
 import static org.junit.Assert.assertEquals;
@@ -28,18 +29,18 @@ import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 public class ServiceInfoTest {
-
+    
     private ObjectMapper mapper;
-
+    
     private ServiceInfo serviceInfo;
-
+    
     @Before
     public void setUp() throws Exception {
         mapper = new ObjectMapper();
         mapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
         serviceInfo = new ServiceInfo("testName", "testClusters");
     }
-
+    
     @Test
     public void testSerialize() throws JsonProcessingException {
         String actual = mapper.writeValueAsString(serviceInfo);
@@ -55,8 +56,9 @@ public class ServiceInfoTest {
         assertFalse(actual.contains("key"));
         assertFalse(actual.contains("keyEncoded"));
     }
-
+    
     @Test
+    @SuppressWarnings("checkstyle:linelength")
     public void testDeserialize() throws IOException {
         String example = "{\"name\":\"testName\",\"clusters\":\"testClusters\",\"cacheMillis\":1000,\"hosts\":[],\"lastRefTime\":0,\"checksum\":\"\",\"allIPs\":false,\"valid\":true,\"groupName\":\"\"}";
         ServiceInfo actual = mapper.readValue(example, ServiceInfo.class);

api/src/test/java/com/alibaba/nacos/api/naming/pojo/healthcheck/AbstractHealthCheckerTest.java

@@ -16,28 +16,28 @@
 
 package com.alibaba.nacos.api.naming.pojo.healthcheck;
 
-import org.junit.Before;
-import org.junit.Test;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.jsontype.NamedType;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
-import java.io.IOException;
-
 public class AbstractHealthCheckerTest {
-
+    
     private final ObjectMapper objectMapper = new ObjectMapper();
-
+    
     @Before
     public void setUp() {
         objectMapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
         objectMapper.registerSubtypes(new NamedType(TestChecker.class, TestChecker.TYPE));
     }
-
+    
     @Test
     public void testSerialize() throws JsonProcessingException {
         TestChecker testChecker = new TestChecker();
@@ -46,7 +46,7 @@ public class AbstractHealthCheckerTest {
         assertTrue(actual.contains("\"testValue\":\"\""));
         assertTrue(actual.contains("\"type\":\"TEST\""));
     }
-
+    
     @Test
     public void testDeserialize() throws IOException {
         String testChecker = "{\"type\":\"TEST\",\"testValue\":\"\"}";

api/src/test/java/com/alibaba/nacos/api/naming/pojo/healthcheck/HealthCheckerFactoryTest.java

@@ -16,22 +16,21 @@
 
 package com.alibaba.nacos.api.naming.pojo.healthcheck;
 
-import org.junit.Test;
-
 import com.alibaba.nacos.api.naming.pojo.healthcheck.impl.Tcp;
+import org.junit.Test;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 public class HealthCheckerFactoryTest {
-
+    
     @Test
     public void testSerialize() {
         Tcp tcp = new Tcp();
         String actual = HealthCheckerFactory.serialize(tcp);
         assertTrue(actual.contains("\"type\":\"TCP\""));
     }
-
+    
     @Test
     public void testSerializeExtend() {
         HealthCheckerFactory.registerSubType(TestChecker.class, TestChecker.TYPE);
@@ -39,14 +38,14 @@ public class HealthCheckerFactoryTest {
         String actual = HealthCheckerFactory.serialize(testChecker);
         assertTrue(actual.contains("\"type\":\"TEST\""));
     }
-
+    
     @Test
     public void testDeserialize() {
         String tcpString = "{\"type\":\"TCP\"}";
         AbstractHealthChecker actual = HealthCheckerFactory.deserialize(tcpString);
         assertEquals(Tcp.class, actual.getClass());
     }
-
+    
     @Test
     public void testDeserializeExtend() {
         String tcpString = "{\"type\":\"TEST\",\"testValue\":null}";

api/src/test/java/com/alibaba/nacos/api/naming/pojo/healthcheck/TestChecker.java

@@ -20,24 +20,24 @@ import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonTypeInfo.Id;
 
 public class TestChecker extends AbstractHealthChecker {
-
+    
     @JsonTypeInfo(use = Id.NAME, property = "type")
     public static final String TYPE = "TEST";
-
+    
     private String testValue;
-
+    
     public String getTestValue() {
         return testValue;
     }
-
+    
     public void setTestValue(String testValue) {
         this.testValue = testValue;
     }
-
+    
     public TestChecker() {
         super(TYPE);
     }
-
+    
     @Override
     public AbstractHealthChecker clone() throws CloneNotSupportedException {
         return null;

api/src/test/java/com/alibaba/nacos/api/naming/pojo/healthcheck/impl/HttpTest.java

@@ -16,37 +16,36 @@
 
 package com.alibaba.nacos.api.naming.pojo.healthcheck.impl;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.Before;
 import org.junit.Test;
 
+import java.io.IOException;
+import java.util.Map;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
-import java.io.IOException;
-import java.util.Map;
-
-import com.fasterxml.jackson.core.JsonProcessingException;
-import com.fasterxml.jackson.databind.ObjectMapper;
-
 public class HttpTest {
-
+    
     private ObjectMapper objectMapper;
-
+    
     private Http http;
-
+    
     @Before
     public void setUp() {
         objectMapper = new ObjectMapper();
         http = new Http();
     }
-
+    
     @Test
     public void testGetExpectedResponseCodeWithEmpty() {
         http.setHeaders("");
         assertTrue(http.getCustomHeaders().isEmpty());
     }
-
+    
     @Test
     public void testGetExpectedResponseCodeWithoutEmpty() {
         http.setHeaders("x:a|y:");
@@ -55,7 +54,7 @@ public class HttpTest {
         assertEquals(1, actual.size());
         assertEquals("a", actual.get("x"));
     }
-
+    
     @Test
     public void testSerialize() throws JsonProcessingException {
         http.setHeaders("x:a|y:");
@@ -66,7 +65,7 @@ public class HttpTest {
         assertTrue(actual.contains("\"headers\":\"x:a|y:\""));
         assertTrue(actual.contains("\"expectedResponseCode\":200"));
     }
-
+    
     @Test
     public void testDeserialize() throws IOException {
         String testChecker = "{\"type\":\"HTTP\",\"path\":\"/x\",\"headers\":\"x:a|y:\",\"expectedResponseCode\":200}";

api/src/test/java/com/alibaba/nacos/api/naming/pojo/healthcheck/impl/MysqlTest.java

@@ -16,23 +16,22 @@
 
 package com.alibaba.nacos.api.naming.pojo.healthcheck.impl;
 
-import java.io.IOException;
+import com.fasterxml.jackson.core.JsonProcessingException;
-
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.Before;
 import org.junit.Test;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
+import java.io.IOException;
-import com.fasterxml.jackson.databind.ObjectMapper;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 public class MysqlTest {
-
+    
     private ObjectMapper objectMapper;
-
+    
     private Mysql mysql;
-
+    
     @Before
     public void setUp() throws Exception {
         mysql = new Mysql();
@@ -41,7 +40,7 @@ public class MysqlTest {
         mysql.setCmd("cmd");
         objectMapper = new ObjectMapper();
     }
-
+    
     @Test
     public void testSerialize() throws JsonProcessingException {
         String actual = objectMapper.writeValueAsString(mysql);
@@ -50,7 +49,7 @@ public class MysqlTest {
         assertTrue(actual.contains("\"pwd\":\"pwd\""));
         assertTrue(actual.contains("\"cmd\":\"cmd\""));
     }
-
+    
     @Test
     public void testDeserialize() throws IOException {
         String testChecker = "{\"type\":\"MYSQL\",\"user\":\"user\",\"pwd\":\"pwd\",\"cmd\":\"cmd\"}";