该类用于处理,偶数个线程之间的数据交换。比如有两个线程A和B,当A开始运行并准备就绪数据后,它就会等待B开始运行,直到B准备好数据,两个线程马上开始交互数据。如果有三个线程将导致死锁。例子如下:
开启一个缓冲线程池,启动两个线程交换数据,每个线程准备时间采用sleep一段时间来模拟。代码如下:
import java.util.concurrent.Exchanger; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class ExchangerTest { /** * @param args */ public static void main(String[] args) { ExecutorService service = Executors.newCachedThreadPool(); final Exchanger exchanger = new Exchanger(); service.execute(new Runnable(){ public void run() { try{ String data1 = "data1"; System.out.println("线程" + Thread.currentThread().getName() + "正在准备把数据" + data1 + "换出去"); Thread.sleep((long) (Math.random()*10000)); String data2 = (String) exchanger.exchange(data1); System.out.println("线程" + Thread.currentThread().getName() + "换回的数据为:" + data2); }catch(Exception e){ e.printStackTrace(); } } }); service.execute(new Runnable(){ public void run() { try{ String data2 = "data2"; System.out.println("线程" + Thread.currentThread().getName() + "正在准备把数据" + data2 + "换出去"); Thread.sleep((long) (Math.random()*10000)); String data1 = (String) exchanger.exchange(data2); System.out.println("线程" + Thread.currentThread().getName() + "换回的数据为:" + data1); }catch(Exception e){ e.printStackTrace(); } } }); service.shutdown(); } }