多线程编程(二)-Exchanger的使用

wanmin444

• Exchanger的介绍　　类Exchanger的功能可以使两个线程之间传输数据。
  
  
• 方法exchange()的使用
  

　　　　　　　



package com.wjg.unit;
import java.util.concurrent.Exchanger;
public class Run {
public static void main(String[] args) {
Exchanger<String> exchanger = new Exchanger<String>();
Run run =new Run();
ThreadA a = run.new ThreadA(exchanger);
ThreadB b = run.new ThreadB(exchanger);
a.start();
b.start();
}
public class ThreadA extends Thread{
private Exchanger<String> exchanger;
public ThreadA(Exchanger<String> exchanger) {
super();
this.exchanger = exchanger;
}
@Override
public void run() {
try {
String receive = exchanger.exchange("123");
System.out.println("在线程A中获得线程B的值："+receive);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}

public class ThreadB extends Thread{
private Exchanger<String> exchanger;
public ThreadB(Exchanger<String> exchanger) {
super();
this.exchanger = exchanger;
}
@Override
public void run() {
try {
String receive = exchanger.exchange("456");
System.out.println("在线程B中获得线程A的值："+receive);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}

运行结果：
在线程A中获得线程B的值：456
在线程B中获得线程A的值：123


　　方法exchange(V x,long timeout,TimeUnit unit)的使用
　　此方法是指在指定的时间内没有其他线程获取数据，则出现超时异常。



package com.wjg.unit1;
import java.util.concurrent.Exchanger;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
public class Run2 {
public static void main(String[] args) {
Exchanger<String> exchanger = new Exchanger<String>();
Run2 run =new Run2();
ThreadA a = run.new ThreadA(exchanger);
a.start();
}
public class ThreadA extends Thread{
　　        
private Exchanger<String> exchanger;
public ThreadA(Exchanger<String> exchanger) {
super();
this.exchanger = exchanger;
}
@Override
public void run() {
try {
                 //设置超时时间
String receive = exchanger.exchange("123",5,TimeUnit.SECONDS);
System.out.println("在线程A中获得线程B的值："+receive);
} catch (InterruptedException e) {
e.printStackTrace();
} catch (TimeoutException e) {
e.printStackTrace();
}
}
}
}

执行结果：
java.util.concurrent.TimeoutException
    at java.util.concurrent.Exchanger.exchange(Exchanger.java:683)
    at com.wjg.unit1.Run2$ThreadA.run(Run2.java:27)