asyncTool/QuickStart.md

基本组件

worker： 一个最小的任务执行单元。通常是一个网络调用，或一段耗时操作。

T，V两个泛型，分别是入参和出参类型。

譬如该耗时操作，入参是String，执行完毕的结果是Integer，那么就可以用泛型来定义。

多个不同的worker之间，没有关联，分别可以有不同的入参、出参类型。

/**
 * 每个最小执行单元需要实现该接口
 * @author wuweifeng wrote on 2019-11-19.
 */
public interface IWorker<T, V> {
    /**
     * 在这里做耗时操作，如rpc请求、IO等
     *
     * @param object
     *         object
     */
    V action(T object);

    /**
     * 超时、异常时，返回的默认值
     * @return 默认值
     */
    V defaultValue();
}

callBack：对每个worker的回调。worker执行完毕后，会回调该接口，带着执行成功、失败、原始入参、和详细的结果。

/**
 * 每个执行单元执行完毕后，会回调该接口</p>
 * 需要监听执行结果的，实现该接口即可
 * @author wuweifeng wrote on 2019-11-19.
 */
public interface ICallback<T, V> {

    void begin();

    /**
     * 耗时操作执行完毕后，就给value注入值
     *
     */
    void result(boolean success, T param, WorkResult<V> workResult);
}

wrapper：组合了worker和callback，是一个 最小的调度单元 。通过编排wrapper之间的关系，达到组合各个worker顺序的目的。

wrapper的泛型和worker的一样，决定了入参和结果的类型。

        WorkerWrapper<String, String> workerWrapper = new WorkerWrapper<>(w, "0", w);
        WorkerWrapper<String, String> workerWrapper1 = new WorkerWrapper<>(w1, "1", w1);
        WorkerWrapper<String, String> workerWrapper2 = new WorkerWrapper<>(w2, "2", w2);
        WorkerWrapper<String, String> workerWrapper3 = new WorkerWrapper<>(w3, "3", w3);

        workerWrapper.addNext(workerWrapper1, workerWrapper2);
        workerWrapper1.addNext(workerWrapper3);
        workerWrapper2.addNext(workerWrapper3);

如

0执行完,同时1和2, 1\2都完成后3。3会等待2完成

譬如，你可以定义一个 worker

/**
 * @author wuweifeng wrote on 2019-11-20.
 */
public class ParWorker1 implements IWorker<String, String>, ICallback<String, String> {

    @Override
    public String action(String object) {
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return "result = " + SystemClock.now() + "---param = " + object + " from 1";
    }

    @Override
    public String defaultValue() {
        return "worker1--default";
    }

    @Override
    public void begin() {
        //System.out.println(Thread.currentThread().getName() + "- start --" + System.currentTimeMillis());
    }

    @Override
    public void result(boolean success, String param, WorkResult<String> workResult) {
        if (success) {
            System.out.println("callback worker1 success--" + SystemClock.now() + "----" + workResult.getResult()
                    + "-threadName:" +Thread.currentThread().getName());
        } else {
            System.err.println("callback worker1 failure--" + SystemClock.now() + "----"  + workResult.getResult()
                    + "-threadName:" +Thread.currentThread().getName());
        }
    }

}

通过这一个类看一下，action里就是你的耗时操作，begin就是任务开始执行时的回调，result就是worker执行完毕后的回调。当你组合了多个执行单元时，每一步的执行，都在掌控之内。失败了，还会有自定义的默认值。这是CompleteableFuture无法做到的。

安装教程

代码不多，直接拷贝包过去即可。

使用说明

1. 3个任务并行

        ParWorker w = new ParWorker();
        ParWorker1 w1 = new ParWorker1();
        ParWorker2 w2 = new ParWorker2();

        WorkerWrapper<String, String> workerWrapper = new WorkerWrapper<>(w, "0", w);
        WorkerWrapper<String, String> workerWrapper1 = new WorkerWrapper<>(w1, "1", w1);
        WorkerWrapper<String, String> workerWrapper2 = new WorkerWrapper<>(w2, "2", w2);
        long now = SystemClock.now();
        System.out.println("begin-" + now);

        Async.beginWork(1500, workerWrapper, workerWrapper1, workerWrapper2);
//        Async.beginWork(800, workerWrapper, workerWrapper1, workerWrapper2);
//        Async.beginWork(1000, workerWrapper, workerWrapper1, workerWrapper2);

        System.out.println("end-" + SystemClock.now());
        System.err.println("cost-" + (SystemClock.now() - now));
        System.out.println(getThreadCount());

        System.out.println(workerWrapper.getWorkResult());
//        System.out.println(getThreadCount());
        Async.shutDown();

2. 1个执行完毕后，开启另外两个，另外两个执行完毕后，开始第4个

        ParWorker w = new ParWorker();
        ParWorker1 w1 = new ParWorker1();
        ParWorker2 w2 = new ParWorker2();
        w2.setSleepTime(2000);
        ParWorker3 w3 = new ParWorker3();

        WorkerWrapper<String, String> workerWrapper = new WorkerWrapper<>(w, "0", w);
        WorkerWrapper<String, String> workerWrapper1 = new WorkerWrapper<>(w1, "1", w1);
        WorkerWrapper<String, String> workerWrapper2 = new WorkerWrapper<>(w2, "2", w2);
        WorkerWrapper<String, String> workerWrapper3 = new WorkerWrapper<>(w3, "3", w3);

        workerWrapper.addNext(workerWrapper1, workerWrapper2);
        workerWrapper1.addNext(workerWrapper3);
        workerWrapper2.addNext(workerWrapper3);

        long now = SystemClock.now();
        System.out.println("begin-" + now);

        //正常完毕
        Async.beginWork(4100, workerWrapper);
        //3会超时
//        Async.beginWork(3100, workerWrapper);
        //2,3会超时
//        Async.beginWork(2900, workerWrapper);

        System.out.println("end-" + SystemClock.now());
        System.err.println("cost-" + (SystemClock.now() - now));

        System.out.println(getThreadCount());
        Async.shutDown();

3. 复杂点的

在测试类里能找到，下图是执行结果。看时间戳，就知道执行的顺序。每个执行单元都是睡1秒。

4. 其他的详见test包下的测试类，支持各种形式的组合、编排。