Java线程状态(Thread.State)
Posted dddjp
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Java线程状态(Thread.State)相关的知识,希望对你有一定的参考价值。
java.lang.Thread.State
成员内部类
NEW:还未启动
Thread state for a thread which has not yet started.
RUNNABLE:正在jvm中运行,但是可能正在等待操作系统的其他资源
Thread state for a runnable thread.
A thread in the runnable state is executing in the Java virtual machine but it may be waiting for other resources from the operating system such as processor.
BLOCKED:受阻塞,并且正在等待监视器锁
Thread state for a thread blocked waiting for a monitor lock.
A thread in the blocked state is waiting for a monitor lock to enter a synchronized block/method or reenter a synchronized block/method after calling {@link Object#wait() Object.wait}.
WAITING:处于等待状态的线程,正在等待另一个线程执行特定的操作
Thread state for a waiting thread.
A thread is in the waiting state due to calling one of the following methods:
{@link Object#wait() Object.wait} with no timeout
{@link #join() Thread.join} with no timeout
{@link LockSupport#park() LockSupport.park}
A thread in the waiting state is waiting for another thread to perform a particular action.
A thread that has called Object.wait() on an object is waiting for another thread to call Object.notify() or Object.notifyAll() on that object.
A thread that has called Thread.join() is waiting for a specified thread to terminate.
TIMED_WAITING
Thread state for a waiting thread with a specified waiting time.
A thread is in the timed waiting state due to calling one of the following methods with a specified positive waiting time:
{@link #sleep Thread.sleep}
{@link Object#wait(long) Object.wait} with timeout
{@link #join(long) Thread.join} with timeout
{@link LockSupport#parkNanos LockSupport.parkNanos}
{@link LockSupport#parkUntil LockSupport.parkUntil}
TERMINATED
Thread state for a terminated thread.
The thread has completed execution.
Thread start()
sleep() sleep(?)
join()
Object wait() notify() notifyAll()
wait(?)
新建(new)
可运行(Runnable)
阻塞(block)
无限期等待(waiting)
限期等待(TIMED_WAITING)
结束(terminated)
新创建一个线程,线程处于新建状态(new)
使用重载的new Thread()创建一个新的线程
调用线程的start()方法,线程进入可运行状态(Runnable)
Java线程中的Runnable状态包括操作系统线程的running和ready状态,处于就绪状态的线程一旦获得CPU使用权,进入运行状态
即处于Runnable状态的线程可能正在运行,也可能正在等待CPU分配时间片
调用Thread类的start()方法之后
一个线程处于等待(waiting)状态,表示该线程正在等待其它线程执行特定的操作
例如,一个线程调用了Object类的空参的wait方法,表示该线程等待其它线程调用该对象的notify或者notifyAll方法
一个线程调用了Thread类的空参的join方法,表示该线程在等待一个特定的线程终止
何时进入waiting状态:
调用Object类空参的wait()
调用Thread类空参的join()
一个线程在执行过程中,想获得某一资源的锁,但是该资源又被其它线程占用,此时,当前线程处于阻塞状态(例如,进入一个同步方法或者同步代码块,要先获得锁)
阻塞和等待的不同是,阻塞状态是在等待一个排它锁
等待状态实在等待一个事件的发生,如等待时间到,唤醒方法被调用
一个线程处于超时等待状态(timed_waiting),和waiting不同的是,将在特定的时间内自行返回
何时进入timed_waiting状态:
调用Object类有参的wait()
调用Thread类有参的join()
调用Thread类的sleep方法(sleep方法没有空参的重载形式)
一个线程执行完毕,进入终止状态(terminated)
线程执行完毕
线程在执行过程中抛出异常
以上是关于Java线程状态(Thread.State)的主要内容,如果未能解决你的问题,请参考以下文章
线程处于 WAITING 状态:java.lang.Thread.State: WAITING (parking) at sun.misc.Unsafe.park(Native Method)