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我正在Android Studio中学习该工具，获取线程转储，如下：

获取线程转储

我注意到每个线程的不同状态是这样的，

在此处输入图像描述

我可以看到有runnable, sleeping, waiting. 而我深入线程栈，大部分线程栈都是这样的，

"<61> RxComputationScheduler-3@830064517520" daemon prio=5 waiting
    java.lang.Thread.State: WAITING
        at java.lang.Object.wait(Object.java:-1)
        at java.lang.Thread.parkFor(Thread.java:1205)
        at sun.misc.Unsafe.park(Unsafe.java:325)
        at java.util.concurrent.locks.LockSupport.park(LockSupport.java:157)
        at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2017)
        at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1050)
        at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:778)
        at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1035)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1097)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
        at java.lang.Thread.run(Thread.java:841)

我很困惑他们都停止了，Object.wait但是线程的状态可以是runnable，，？sleepingwaiting

这是另一个状态线程的堆栈。

RUNNABLE

<53> RxSchedulerPurge-1@830057651944" daemon prio=5 runnable
  java.lang.Thread.State: RUNNABLE
      at java.lang.Object.wait(Object.java:-1)
      at java.lang.Thread.parkFor(Thread.java:1205)
      at sun.misc.Unsafe.park(Unsafe.java:325)
      at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:197)
      at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2056)
      at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1062)
      at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:778)
      at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1035)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1097)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
      at java.lang.Thread.run(Thread.java:841)</code>

TIMED_WAITING

<58> RxScheduledExecutorPool-2@830064740632" daemon prio=5 sleeping
  java.lang.Thread.State: TIMED_WAITING
      at java.lang.Object.wait(Object.java:-1)
      at java.lang.Thread.parkFor(Thread.java:1205)
      at sun.misc.Unsafe.park(Unsafe.java:325)
      at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:197)
      at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2056)
      at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1062)
      at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:778)
      at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1035)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1097)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
      at java.lang.Thread.run(Thread.java:841)
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2 回答 2

5

Thread如果您在调用方法之前创建类的实例，则New表示线程处于新状态start()：

Thread t = new Thread(...); // t is New

Runnable表示调用方法后线程处于可运行状态start()。基本上：

t.start(); // t is Runnable

Running是Runnable的“子状态” ：如果线程调度程序选择了线程，则线程处于运行状态。你不能明确地用它做任何事情，这意味着你打电话start()然后等待。

Ready是Runnable的另一个“子状态” ：线程有资格运行并等待线程调度程序选择它。

Blocked表示线程仍然活着但当前没有资格运行时的状态。例如，当一个线程遇到synchronized由另一个线程处理的块时，就会发生这种情况。在这种情况下，第一个线程被阻塞。

等待是您的线程既未阻塞也未就绪时的状态。这通常发生在您调用wait()或join()在线程上。

Thread t1 = new Thread(); // t1 is New
Thread t2 = new Thread(); // t2 is New
t1.start(); // t1 becomes Runnable
t2.start(); // t2 becomes Runnable
t1.join(); // t2 becomes Waiting, because t1 is processed until it terminates

还有一种状态叫做Timed Waiting，几乎是一样的东西，只不过是调用引起的sleep()。如果你调用wait(timeout)or join(timeout)，线程也会进入定时等待状态。

Thread t = new Thread(); // t is New
t.start(); // t is Runnable
t.sleep(4000); // t get state of Timed Waiting for 4 seconds

Terminatedrun()是当它的方法退出时处于终止或死状态的线程。

我想我已经涵盖了所有内容：）这是一张可以帮助您更清楚地理解它的图片：

线程生命周期 Java

按照 JoxTraex 的要求，以下是我在发布前阅读的资源：

  1. https://docs.oracle.com/javase/7/docs/api/java/lang/Thread.State.html
  2. javarush.ru
  3. http://www.uml-diagrams.org/examples/java-6-thread-state-machine-diagram-example.html
  4. http://www.journaldev.com/1044/thread-life-cycle-in-java-thread-states-in-java

这只是一个良好的谷歌搜索技能的问题，真的......

于 2016-10-26T03:25:38.823 回答
2 
public static enum Thread.State
extends Enum<Thread.State>

线程状态。线程可以处于以下状态之一：

NEW
A thread that has not yet started is in this state.

RUNNABLE
A thread executing in the Java virtual machine is in this state.

BLOCKED
A thread that is blocked waiting for a monitor lock is in this state.

WAITING
A thread that is waiting indefinitely for another thread to perform a particular action is in this state.

TIMED_WAITING
A thread that is waiting for another thread to perform an action for up to a specified waiting time is in this state.

TERMINATED
A thread that has exited is in this state.

一个线程在给定的时间点只能处于一种状态。这些状态是不反映任何操作系统线程状态的虚拟机状态。

请参阅oracle 的 api以获取更多信息。

于 2016-10-26T03:20:36.090 回答