多线程学习2-线程的创建

1.java的多线程：
运行下面代码并得到结果：

public static void main(String[] args){
        ThreadMXBean tmb = ManagementFactory.getThreadMXBean();
        ThreadInfo[] threadInfos = tmb.dumpAllThreads(false,false);
        for (ThreadInfo threadInfo : threadInfos){
            System.out.println("[" + threadInfo.getThreadId() + "]  " +threadInfo.getThreadName());
        }

得到结果：

[6]  Monitor Ctrl-Break
[5]  Attach Listener
[4]  Signal Dispatcher
[3]  Finalizer
[2]  Reference Handler
[1]  main

2.启动线程的三种方式：
(1)继承Thread类;
(2)实现Runnable接口；
(3)实现Callable接口；
示例代码如下：

public class NewThread {
    static class ExtendsThread extends Thread{
        @Override
        public void run() {
            System.out.println("I am extends Thread !");
        }
    }
    static class RunThread implements Runnable{
        @Override
        public void run() {
            System.out.println("I am implemments Runnable !");
        }
    }
    static class CallThread implements Callable<String>{
        @Override
        public String call() throws Exception {
            System.out.println("I am implements Callable !");
            return "call";
        }
    }

    public static void main(String[] args) throws ExecutionException, InterruptedException {
        ExtendsThread extendsThread = new ExtendsThread();
        extendsThread.start();

        RunThread runThread = new RunThread();
        new Thread(runThread).start();

        CallThread callThread = new CallThread();
        FutureTask futureTask = new FutureTask(callThread);
        new Thread(futureTask).start();
        // get()方法是阻塞的
        System.out.println(futureTask.get());
    }
}

运行结果如下：

I am implemments Runnable !
I am extends Thread !
I am implements Callable !
call