确保按顺序获取 Java 同步锁?

本文介绍了确保按顺序获取 Java 同步锁?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我们有两个线程通过同步方法访问一个列表.我们可以

we have two threads accessing one list via a synchronized method. Can we

a) 依靠运行时间来确保他们每个人都将根据他们尝试的顺序获得对该方法的访问权限或

a) rely on the run time to make sure that each of them will receive access to the method based on the order they tried to or

b) 虚拟机是否遵循任何其他规则

b) does the VM follow any other rules

c) 有没有更好的方法来序列化请求?

c) is there a better way to serialize the requests?

推荐答案

不，同步将按任意顺序授予访问权限(取决于 JVM 实现).这甚至可能导致线程在某些情况下饿死.

No, synchronized will give access in any order (Depends on the JVM implementation). This could even cause Threads to starve in some scenarios.

您可以使用 ReentrantLock(从 Java 5.0 开始)带有 fair=true 选项.(Lock lock = new ReentrantLock(true);)

You can ensure the order by using ReentrantLock (since Java 5.0) with the fair=true option. (Lock lock = new ReentrantLock(true);)