转换等待& notifyAll代码使用Java 1.5 Lock对象 [英] Convert wait & notifyAll code to use Java 1.5 Lock object

问题描述

我们使用的代码使用代码段周围的同步块，有很多wait和notifyAll（）调用。我们试图将这些转换为使用Java 5 Lock.lock（）和Lock.unlock（）方法。如何迁移此代码以删除所有等待和notifyAll调用。我不知道相当于这些使用新的锁定功能。

We use code that uses syncronized blocks around segments of code with a lot of wait and notifyAll() calls. We are trying to convert these to use Java 5 Lock.lock() and Lock.unlock() methods. How do I migrate this code to remove all the wait and notifyAll calls. I do not know the equivalent to these using the new Locking features.

任何链接的例子将不胜感激。

Any links with examples would be appreciated.

感谢进行

方程式，下面的代码需要转换为使用Lock.lock（）和lock.unlock删除同步块的第一部分是简单，因为我只需要调用lock（）方法。问题是对notifyAll（）和等待方法可以做什么。

Eq., the following code needs to be converted to use Lock.lock() and lock.unlock The first part to remove the synchronized block is simple as I just need to call lock() method. The question is what can be done for the notifyAll() and wait methods.

     synchronized( LOCK )
            {
                while( !Thread.interrupted() )
                {
                 try
                    {

                        working = runRules();

                        if( !working )
                            LOCK.notifyAll();

                        LOCK.wait( working ? shortTimeout : longTimeout );
                    }
                    catch( final InterruptedException e )
                    {
                        Package.log.info( "Thread was interrupted.  Exiting.", e );
                        return;
                    }
                }
            }

推荐答案

a href =http://download.oracle.com/javase/1.5.0/docs/api/java/util/concurrent/locks/Condition.html> 条件 java.util.concurrent.locks 包提供的

Use the Conditions provided by the java.util.concurrent.locks package:

 final Object monitor = ...

 ...

 synchronized (monitor) {

     while (!condition) monitor.wait();
     ... do something ...
 }

p>

becomes:

 final ReentrantLock lock = ...;
 final Condition cvar = lock.newCondition();

 ...

 lock.lock();

 try {

     while (!condition) cvar.await();
     ... do something ... 

 } finally {

     lock.unlock();
 }

信号端非常相似：

 synchronized (monitor) {

      ... do something ...
      monitor.notify();
 }

变为：

 lock.lock();

 try {

     ... do something ...
     cvar.signalAll();

 } finally {

     lock.unlock();
 }

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