diff --git a/java/09_queue/CircularQueue.java b/java/09_queue/CircularQueue.java
index c3c54cc..71a988c 100644
--- a/java/09_queue/CircularQueue.java
+++ b/java/09_queue/CircularQueue.java
@@ -36,7 +36,8 @@ public class CircularQueue {
   }
 
   public void printAll() {
-    for (int i = head; i < tail; ++i) {
+    if (0 == n) return;
+    for (int i = head; i % n != tail; ++i) {
       System.out.print(items[i] + " ");
     }
     System.out.println();
diff --git a/java/09_queue/DynimacArrayQueue.java b/java/09_queue/DynamicArrayQueue.java
similarity index 94%
rename from java/09_queue/DynimacArrayQueue.java
rename to java/09_queue/DynamicArrayQueue.java
index 3a19fa3..9faad0f 100644
--- a/java/09_queue/DynimacArrayQueue.java
+++ b/java/09_queue/DynamicArrayQueue.java
@@ -3,7 +3,7 @@ package queue;
 /**
  * Created by wangzheng on 2018/10/9.
  */
-public class DynimacArrayQueue {
+public class DynamicArrayQueue {
   // 数组：items，数组大小：n
   private String[] items;
   private int n = 0;
@@ -12,7 +12,7 @@ public class DynimacArrayQueue {
   private int tail = 0;
 
   // 申请一个大小为capacity的数组
-  public DynimacArrayQueue(int capacity) {
+  public DynamicArrayQueue(int capacity) {
     items = new String[capacity];
     n = capacity;
   }