Java多線程 callable和future

package advanced.java;

import java.util.Random;
import java.util.concurrent.*;

/**
 * callable和future是試驗類
 *
 * @author: cuiH
 * Date: 13-11-27
 * 執行一個線程，取得線程返回的結果
 * callable 返回一個結果，future取到返回的結果。
 */
public class CallableAndFuture {
    public static void main(String[] args) throws ExecutionException, InterruptedException, TimeoutException {
        ExecutorService threadPool = Executors.newSingleThreadExecutor();
        Future<String> future = threadPool.submit(new Callable<String>() {
            @Override
            public String call() throws Exception {
                Thread.sleep(200);
                return "Hello Honey";
            }
        });//提交返回的結果
        System.out.println("等待結果");
        System.out.println("拿到結果:" + future.get(1, TimeUnit.SECONDS));
        //future能夠添加參數，此處超過一秒沒有取到，我就不取了

        ExecutorService threadPool2 = Executors.newFixedThreadPool(10);


        //提交一批量的結果，而後，馬上得到先得到的結果，同時捕獲。應用須要查找
        CompletionService<Integer> completionService = new ExecutorCompletionService<Integer>(threadPool2);
        for (int i = 0; i < 10; i++) {
            final int finalI = i;
            completionService.submit(new Callable<Integer>() {
                @Override
                public Integer call() throws Exception {
                    Thread.sleep(new Random().nextInt(5000));
                    return finalI;
                }
            });
        }
        for (int i = 0; i < 10; i++) {
            System.out.println(completionService.take().get());
        }
    }
}