java线程数据交换Exchanger

两个线程都等到交换函数才能完成交换数据操作，代码如下：

package threadLock;

import java.util.Random;
import java.util.concurrent.Exchanger;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ExchangerTest {

    public static void main(String[] args) {
        final Exchanger<String> ex = new Exchanger<String>();
        ExecutorService service = Executors.newCachedThreadPool();
        service.execute(new  Runnable() {
            public void run() {
                String data1 = "";
                System.out.println("线程" + Thread.currentThread().getName() + "正在把" + "\"" + data1 + "\"交换出去" );
                try {
                    Thread.sleep(new Random().nextInt());
                    String data2 = ex.exchange(data1);
                    System.out.println("线程" + Thread.currentThread().getName() + "交换后的数据为\"" + data2 + "\"");
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });
        service.execute(new Runnable() {

            @Override
            public void run() {
                String data1 = "gghhh";
                System.out.println("线程" + Thread.currentThread().getName() + "正在把" + "\"" + data1 + "\"交换出去" );
                try {
                    Thread.sleep(new Random().nextInt());
                    String data2 = ex.exchange(data1);
                    System.out.println("线程" + Thread.currentThread().getName() + "交换后的数据为\"" + data2 + "\"");
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });

        service.shutdown();
    }
}