java并发编程实战-CyclicBarrier和FutureTask使用

import java.util.concurrent.Callable;
import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.FutureTask;

public class FutureTest {

public static void main(String[] args) {
new FutureTest().test();
}

public void test() {
// 设置7个线程栅栏，为什么6个线程要设置7个栅栏，因为需要阻塞本线程等待6个线程的执行结果
        final CyclicBarrier cb = new CyclicBarrier(7);
        // 创建6个服务
        final Service[] assembles = new Service[6];
        final FutureTask[] futureTasks = new FutureTask[6];
        final Domain domain = new Domain();
        assembles[0] = new Service0();
        assembles[1] = new Service1();
        assembles[2] = new Service2();
        assembles[3] = new Service3();
        assembles[4] = new Service4();
        assembles[5] = new Service5();
        for(int i = 0; i < 6; i++) {
            final int fi = i;
            futureTasks[i] = new FutureTask<Integer>(new Callable<Integer>() {  
                @Override  
                public Integer call() throws Exception { 
                try {
                assembles[fi].assemble(domain);
                        System.out.println(fi + "assemble");
                } finally {
                cb.await();
                }
                return fi;
                }  
            });
            new Thread(futureTasks[i]).start(); 
        }
        try {
            cb.await();
        } catch (Exception e) {
            System.err.println(e);
        }
        for(int i = 0; i < 6; i++) {
        try {
        System.out.println(futureTasks[i].get());
} catch (Exception e) {
// 获取Service5抛出的异常
System.err.println(e);
} 
        }
        System.out.println(domain);
    }

interface Service {
void assemble(Domain domian);
}
class Domain{
public String t0;
public String t1;
public String t2;
public String t3;
public String t4;
@Override
public String toString() {
return t0 + "-" +t1 + "-" +t2 + "-" +t3 + "-" + t4;
}
}
class Service0 implements Service {
@Override
public void assemble(Domain domian) {
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
System.err.println(e);
}
domian.t0 = "0";
}
}
class Service1 implements Service {
@Override
public void assemble(Domain domian) {
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
System.err.println(e);
}
domian.t1 = "1";
}
}
class Service2 implements Service {
@Override
public void assemble(Domain domian) {
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
System.err.println(e);
}
domian.t2 = "2";
}
}
class Service3 implements Service {
@Override
public void assemble(Domain domian) {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
System.err.println(e);
}
domian.t3 = "3";
}
}
class Service4 implements Service {
@Override
public void assemble(Domain domian) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
System.err.println(e);
}
domian.t4 = "4";
}
}
class Service5 implements Service {
@Override
public void assemble(Domain domian) {
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
System.err.println(e);
}
throw new RuntimeException();
}
}
}