可能重复:
每次都尝试以特定顺序循环 3 个线程
我想一个接一个地从两个线程访问同一对象的两个不同方法。这是我的代码,
public class ThreadCoordination
{
private Thread threadSayHello;
private Thread threadSayWorld;
private boolean threadSayWorldStarted = false;
public ThreadCoordination()
{
createThreads();
}
private void createThreads()
{
threadSayWorld = new Thread(new Runnable()
{
public void run()
{
try
{
// while (true)
{
sayWorld();
}
}
catch (InterruptedException ex)
{}
}
});
threadSayHello = new Thread(new Runnable()
{
public void run()
{
try
{
// while (true)
{
sayHello();
if (!threadSayWorldStarted)
{
threadSayWorldStarted = true;
threadSayWorld.start();
}
}
}
catch (InterruptedException ex)
{}
}
});
threadSayHello.start();
}
private synchronized void sayHello() throws InterruptedException
{
System.out.print("Hello ");
}
private synchronized void sayWorld() throws InterruptedException
{
System.out.println("World!");
}
public static void main(String[] args)
{
new ThreadCoordination();
}
}
如果我取消注释调用 while(true),那么我会期待这样的输出,
Hello World!
Hello World!
Hello World!
Hello World!
...
请指导我该怎么做。拉贾。
我不知道我是否可以编辑已关闭的帖子。据我所知,我只想发布解决方案。
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;
public class SequenceAccess
{
private ReentrantLock myLock;
private Condition ensureSequence;
private int sequenceNo = 1;
public SequenceAccess()
{
myLock = new ReentrantLock();
ensureSequence = myLock.newCondition();
startThreads();
}
private void startThreads()
{
new Thread(new Runnable()
{
public void run()
{
try
{
while (true)
method1();
}
catch (InterruptedException ex)
{}
}
}).start();
new Thread(new Runnable()
{
public void run()
{
try
{
while (true)
method2();
}
catch (InterruptedException ex)
{}
}
}).start();
new Thread(new Runnable()
{
public void run()
{
try
{
while (true)
method3();
}
catch (InterruptedException ex)
{}
}
}).start();
}
private void method1() throws InterruptedException
{
myLock.lock();
try
{
while (sequenceNo != 1)
ensureSequence.await();
sequenceNo = 2;
System.out.println("Method 1");
ensureSequence.signalAll();
}
finally
{
myLock.unlock();
}
}
private void method2() throws InterruptedException
{
myLock.lock();
try
{
while (sequenceNo != 2)
ensureSequence.await();
sequenceNo = 3;
System.out.println("Method 2");
ensureSequence.signalAll();
}
finally
{
myLock.unlock();
}
}
private void method3() throws InterruptedException
{
myLock.lock();
try
{
while (sequenceNo != 3)
ensureSequence.await();
sequenceNo = 1;
System.out.println("Method 3");
ensureSequence.signalAll();
}
finally
{
myLock.unlock();
}
}
public static void main(String[] args)
{
new SequenceAccess();
}
}