线程池Executors、Callable与Future的应用

package cn.itcast.heima;

import java.util.Random;
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;

/**
* Callable与Future的应用
* @ClassName: CallableAndFuture
* @Description: TODO
* @author honghao
* @date 2016年8月10日 下午4:24:33
*/
public class CallableAndFuture {
public static void main(String[] args) {
ExecutorService executorService = Executors.newSingleThreadExecutor();
Future<String> future = executorService.submit(new Callable<String>() {
@Override
public String call() throws Exception {
Thread.sleep(1000);
return "hello";
}
});
try {
System.out.println("等待结果");
System.out.println(future.get());
executorService.shutdown();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}

ExecutorService executorService2 = Executors.newFixedThreadPool(10);
CompletionService<Integer> completionService = new ExecutorCompletionService<Integer>(
executorService2);
for (int i = 0; i < 10; i++) {
final int seq = i;
completionService.submit(new Callable<Integer>() {
@Override
public Integer call() throws Exception {
return seq;
}
});
}

for (int i = 0; i < 10; i++) {
try {
Thread.sleep(new Random().nextInt(3000));
System.out.println(completionService.take().get());
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
executorService.shutdown();
executorService2.shutdown();
}
}