通过annomyous内部类创建线程

Question

我正在开发创建线程的代码,但没有扩展线程类或实现runnable接口,即通过匿名内部类.

public class Mythread3 {
    public static void main(String... a) {

        Thread th = new Thread() {

            public synchronized void run() {
                for (int i = 0; i < 20; i++) {
                    try {
                        Thread.sleep(1000);

                        System.out.print(i + "\n" + "..");
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            }

        };

        th.start();
        Thread y = new Thread();
        y.start();

    }
}

现在请告诉我,我也可以用同样的方法创建子线程.!! 我试过的是......

public class Mythread3 {
    public static void main(String... a) {

        Thread th = new Thread() {

            public synchronized void run() {
                for (int i = 0; i < 20; i++) {
                    try {
                        Thread.sleep(1000);

                        System.out.print(i + "\n" + "..");
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            }

        };

        Thread th1 = new Thread() {

            public synchronized void run() {
                for (int i = 0; i < 20; i++) {
                    try {
                        Thread.sleep(1000);

                        System.out.print(i + "\n" + "..");
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            }

        };
        th.start();
        try {
            th.join();
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        th1.start();

    }
}

但是它有两个run()方法,我认为这不实用..请指教..!

Answer 1

 Runnable run = new Runnable() {
    public void run() {
        try {
            for (int i = 0; i < 20; i++) {
                Thread.sleep(1000);
                System.out.print(i + "\n" + "..");
            }

        } catch (InterruptedException e) {
            System.out.println(" interrupted");
        }
    }
 };
 new Thread(run).start();
 new Thread(run).start();

不要等到一个人在开始第二个之前完成,或者你有三个线程在哪一个上运行(在这种情况下,额外的线程是没有意义的)

BTW:你的synchronized没有做任何有用的事情,但它可能会导致Thread无法正常工作.