Java多线程并发编程 Synchronized关键字

public class Test {  private static class Counter {    public synchronized void count() {      for (int i = 0; i < 6; i++) {        System.out.println(Thread.currentThread().getName() + "， i = " + i);      }    }  }  private static class MyThread extends Thread {    private Counter mCounter;    public MyThread(Counter counter) {      mCounter = counter;    }    @Override    public void run() {      super.run();      mCounter.count();    }  }  public static void main(String[] var0) {    Counter counter = new Counter();    // 注：myThread1 和 myThread2 是调用同一个对象 counter    MyThread myThread1 = new MyThread(counter);    MyThread myThread2 = new MyThread(counter);    myThread1.start();    myThread2.start();  }}