【Java】Java多线程

线程相关概念

• 一个进程至少有一个线程
• 在Java中，一个进程至少有两个线程，一个是main线程，一个是垃圾回收线程
• 守护线程：JVM会在只剩下守护线程的时候结束，也就是说所有非守护线程结束，JVM就会结束
  - 典型例子：main线程（非守护线程，不能设置成守护线程），垃圾回收线程（守护线程）
• 线程的状态：NEW、RUNNABLE、BLOCKED、WAITING、TIMED_WAITING、TERMINATED
• 线程优先级：[1,10]. 优先级越高不代表一定优先于优先级低的线程执行，而是会比低的得到更多的CPU资源
• 打印线程的相关信息

        System.out.println("getName: "+Thread.currentThread().getName());
        System.out.println("getContextClassLoader: "+Thread.currentThread().getContextClassLoader());
        System.out.println("getId: "+Thread.currentThread().getId());
        System.out.println("getPriority: "+Thread.currentThread().getPriority());
        System.out.println("getStackTrace: "+Thread.currentThread().getStackTrace());
        System.out.println("getState: "+Thread.currentThread().getState());
        System.out.println("getThreadGroup: "+Thread.currentThread().getThreadGroup());
        System.out.println("getUncaughtExceptionHandler: "+Thread.currentThread().getUncaughtExceptionHandler());
        System.out.println("getClass: "+Thread.currentThread().getClass());
        System.out.println("toString: "+Thread.currentThread().toString());
        System.out.println("isAlive: "+Thread.currentThread().isAlive());
        System.out.println("isDaemon: "+Thread.currentThread().isDaemon());
        System.out.println("isInterrupted: "+Thread.currentThread().isInterrupted());
        System.out.println("Thread: "+Thread.currentThread());

创建线程的四种方式

• 继承Thread
• Runnable
• Callable
• 线程池