Java利用future及时获取多线程运行结果

import java.util.ArrayList;import java.util.List;import java.util.Random;import java.util.concurrent.Callable;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;/** * 多线程执行，异步获取结果 *  * @author i-clarechen * */public class AsyncThread {  public static void main(String[] args) {    AsyncThread t = new AsyncThread();    List<Future<String>> futureList = new ArrayList<Future<String>>();    t.generate(3, futureList);    t.doOtherThings();    t.getResult(futureList);  }  /**   * 生成指定数量的线程，都放入future数组   *    * @param threadNum   * @param fList   */  public void generate(int threadNum, List<Future<String>> fList) {    ExecutorService service = Executors.newFixedThreadPool(threadNum);    for (int i = 0; i < threadNum; i++) {      Future<String> f = service.submit(getJob(i));      fList.add(f);    }    service.shutdown();  }  /**   * other things   */  public void doOtherThings() {    try {      for (int i = 0; i < 3; i++) {        System.out.println("do thing no:" + i);        Thread.sleep(1000 * (new Random().nextInt(10)));      }    } catch (InterruptedException e) {      e.printStackTrace();    }  }  /**   * 从future中获取线程结果，打印结果   *    * @param fList   */  public void getResult(List<Future<String>> fList) {    ExecutorService service = Executors.newSingleThreadExecutor();    service.execute(getCollectJob(fList));    service.shutdown();  }  /**   * 生成指定序号的线程对象   *    * @param i   * @return   */  public Callable<String> getJob(final int i) {    final int time = new Random().nextInt(10);    return new Callable<String>() {      @Override      public String call() throws Exception {        Thread.sleep(1000 * time);        return "thread-" + i;      }    };  }  /**   * 生成结果收集线程对象   *    * @param fList   * @return   */  public Runnable getCollectJob(final List<Future<String>> fList) {    return new Runnable() {      public void run() {        for (Future<String> future : fList) {          try {            while (true) {              if (future.isDone() && !future.isCancelled()) {                System.out.println("Future:" + future                    + ",Result:" + future.get());                break;              } else {                Thread.sleep(1000);              }            }          } catch (Exception e) {            e.printStackTrace();          }        }      }    };  }}

do thing no:0do thing no:1do thing no:2Future:java.util.concurrent.FutureTask@68e1ca74,Result:thread-0Future:java.util.concurrent.FutureTask@3fb2bb77,Result:thread-1Future:java.util.concurrent.FutureTask@6f31a24c,Result:thread-2

import java.util.Random;import java.util.concurrent.BlockingQueue;import java.util.concurrent.Callable;import java.util.concurrent.CompletionService;import java.util.concurrent.ExecutionException;import java.util.concurrent.ExecutorCompletionService;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;import java.util.concurrent.LinkedBlockingDeque;public class testCallable {  public static void main(String[] args) {    try {      completionServiceCount();    } catch (InterruptedException e) {      e.printStackTrace();    } catch (ExecutionException e) {      e.printStackTrace();    }  }  /**   * 使用completionService收集callable结果   * @throws ExecutionException    * @throws InterruptedException    */  public static void completionServiceCount() throws InterruptedException, ExecutionException {    ExecutorService executorService = Executors.newCachedThreadPool();    CompletionService<Integer> completionService = new ExecutorCompletionService<Integer>(        executorService);    int threadNum = 5;    for (int i = 0; i < threadNum; i++) {      completionService.submit(getTask(i));    }    int sum = 0;    int temp = 0;    for(int i=0;i<threadNum;i++){      temp = completionService.take().get();      sum += temp;      System.out.print(temp + "/t");    }    System.out.println("CompletionService all is : " + sum);    executorService.shutdown();  }  public static Callable<Integer> getTask(final int no) {    final Random rand = new Random();    Callable<Integer> task = new Callable<Integer>() {      @Override      public Integer call() throws Exception {        int time = rand.nextInt(100)*100;        System.out.println("thead:"+no+" time is:"+time);        Thread.sleep(time);        return no;      }    };    return task;  }}

thead:0 time is:4200thead:1 time is:6900thead:2 time is:2900thead:3 time is:9000thead:4 time is:7100  0  1  4  3  CompletionService all is : 10