如何创建三个线程的循环交换？即：第一个线程必须向第二个线程发送数据，第二个线程必须向第三个线程发送数据，第三个线程必须向第一个线程发送数据。
我写了一些代码，但是线程以随机顺序交换。
class DataClass {
int value;
String message;
DataClass(int v, String s) {
value = v;
message = s;
}
int getValue() {
return (value);
}
String getMassage() {
return (message);
}
}
class Loop implements Runnable {
int counter;
String name;
Exchanger<DataClass> exchanger;
Loop(int startValue, String id, Exchanger<DataClass> ex) {
counter = startValue;
name = id;
exchanger = ex;
System.out.println(name + ": created");
}
public void run() {
System.out.println(name + ": started");
DataClass data = new DataClass(counter, name);
for (int i = 0; i < 3; ++i) {
try {
DataClass newData = exchanger.exchange(data);
counter += newData.getValue();
System.out.println(name + ": from "
+ newData.getMassage() + ": data: "
+ newData.getValue() + ": state = " + counter);
} catch (InterruptedException e) {
System.err.println(e.toString());
}
}
System.out.println(name + ": ended");
}
}
public class ExchangerDemo {
public static void main(String args[]) {
System.out.println("Main process started");
Exchanger<DataClass> exchanger = new Exchanger<DataClass>();
Loop loop1 = new Loop(1, "First", exchanger);
Loop loop2 = new Loop(2, "Second", exchanger);
Loop loop3 = new Loop(3, "Third", exchanger);
new Thread(loop1).start();
new Thread(loop2).start();
new Thread(loop3).start();
System.out.println("Main process ended");
}
}