Jdk源码之Thread类详解

Jdk源码之Thread类详解

• ​​setDaemon()​​方法的释义

/**
     Marks this thread as either a linkplain #isDaemon daemon thread
     or a user thread. The Java Virtual Machine exits when the only
     threads running are all daemon threads.
   标记这个线程作为一个linkplain isDaemon() daemon线程或者是一个用户线程。仅仅当运行的线程是所有的守护线程时，java虚拟机则会退出。

     This method must be invoked before the thread is started.
   这个方法必须在线程被启动时调用。

     @param  on
             if {@code true}, marks this thread as a daemon thread
        如果参数on为true，则标记这个线程是一个守护线程

     @throws  IllegalThreadStateException
              if this thread is {@linkplain #isAlive alive}

     @throws  SecurityException
              if {@link #checkAccess} determines that the current
              thread cannot modify this thread
     */

• ​​setDaemon()​​方法的代码

public final void setDaemon(boolean on) {
        checkAccess();
        if (isAlive()) {
            throw new IllegalThreadStateException();
        }
        daemon = on;
    }