Status of the thread

State of thread

• The initial state （NEW）： Thread created , But not yet called start() Method .
• Running state （RUNNABLE）：Java The two states of ready and running are generally called running in the thread .
• Blocking (BLOCKED)： Indicates that the thread is blocked by a lock .
• wait for (WAITING)： A thread entering this state needs to wait for some specific action from another thread （ Notification or interruption ）.
• Overtime waiting (TIMED_WAITING)： This state is different from WAITING, It can return on its own after a specified time .
• End (TERMINATED)： Indicates that the thread has finished executing .

Thread state transition diagram

Thread state details

1、 The initial state
Realization Runnable Interfaces and inheritance Thread You can get a thread class ,new An example comes out , The thread is in its initial state .
2、 Running state
Ready state ：

1. Ready state just means that you are qualified to run , The scheduler didn't pick you , You are always ready .
2. Calling thread's start() Method , This thread is in ready state .
3. Current thread sleep() Method end , Other threads join() end , Wait for user input to complete , A thread gets the object lock , These threads will also be ready .
4. The current thread time slice is used up , Call the... Of the current thread yield() Method , The current thread is in ready state .
5. After the thread in the lock pool gets the object lock , Get ready .

In-service state ：
The thread scheduler selects a thread from the runable pool as the current thread's state . This is also the only way for a thread to enter a running state .
3、 Blocked state
The blocking state is that the thread is blocking into synchronized Keyword decorated method or code block ( Get the lock ) State of .
4、 Wait state
Threads in this state are not allocated CPU execution time , They wait to be awakened explicitly , Otherwise it will be in a state of waiting indefinitely .
5、 Timeout wait status
Threads in this state are not allocated CPU execution time , But there is no need to wait indefinitely for other threads to wake up , They wake up automatically after a certain time .
6、 Termination status

1. Thread run() When the method is complete , Or the main thread 's main() When the method is complete , We think it's over . This thread object may be alive , But it's no longer a single thread of execution . Once the thread is terminated , Can't be reborn .
2. Called on a terminated thread start() Method , Will throw out java.lang.IllegalThreadStateException abnormal .