Lock接口

package com.google;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

class Demo {
    private int i = 100;
    Lock lock = new ReentrantLock(); //synchronized

    public void seal() {
        lock.lock();
        try {
            while (i > 0) {
                i = i - 1;
                System.out.println(Thread.currentThread().getName() + "\t" + i);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

}

public class LockDemo {
    public static void main(String[] args) {
        Demo demo = new Demo();
        new Thread(new Runnable() {
            @Override
            public void run() {
                for (int i = 1; i <= 50; i++) {
                    demo.seal();
                }

            }
        }, "AA").start();

        new Thread(new Runnable() {
            @Override
            public void run() {
                for (int i = 1; i <= 50; i++) {
                    demo.seal();
                }
            }
        }, "BB").start();

    }
}