Zookeeper分布式锁解决方案具体代码

定义一个公共资源订单生成类：

package com.itmayiedu.lock;

import java.text.SimpleDateFormat;
import java.util.Date;

//生成订单号规则
public class OrderNumGenerator {
	private static int count = 0;

	//生成订单号规则方法
	
	
	public String orderNumber() {
		SimpleDateFormat simpt = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");
		return simpt.format(new Date()) + "-" + ++count;
	}

}

　　定义一个模拟多线程接口：

package com.itmayiedu.lock;

//订单服务
public class OrderService implements Runnable {
    private OrderNumGenerator orderNumGenerator = new OrderNumGenerator();
    private static Object oj = new Object();
    private Lock lock=new ZookeeperDistrbuteLock();

    public void run() {
        getNumber();
    }

    public void getNumber() {
        // synchronized (oj) {
        lock.getLock();
        String number = orderNumGenerator.orderNumber();
        System.out.println(Thread.currentThread().getName() + ",生成订单号:" + number);
        lock.unLock();

    }

    public static void main(String[] args) {
        for (int i = 0; i < 100; i++) {
            new Thread(new OrderService()).start();
        }
    }

}

定义锁接口：

package com.itmayiedu.lock;

public interface Lock {
    //获取到锁的资源
    public void getLock();
    // 释放锁
    public void unLock();
}

抽象类：

package com.itmayiedu.lock;

import org.I0Itec.zkclient.ZkClient;

//将重复的代码,具体业务逻辑有子类去实现.
public abstract class ZookeeperAbstractLock implements Lock {
    private static final String CONNECT_ADDRES = "192.168.110.159:2181,192.168.110.160:2181,192.168.110.162:2181";
    protected ZkClient zkClient = new ZkClient(CONNECT_ADDRES);
    protected static final String PATH = "/lock";

    public void getLock() {
        // tryLock() 创建zk临时节点 如果创建成功返回true 否则返回false
        if (tryLock()) {
            System.out.println("获取到锁的资源 get lock");
        } else {
            // 等待
            waitLock();
            // 重写获取锁的资源
            getLock();
        }

    }

    protected abstract boolean tryLock();

    protected abstract void waitLock();

    // 释放锁
    public void unLock() {
        if (zkClient != null) {
            zkClient.close();
        }
        System.out.println("释放锁的资源..");

    }

}

实现类：

package com.itmayiedu.lock;

import java.util.concurrent.CountDownLatch;

import org.I0Itec.zkclient.IZkDataListener;

public class ZookeeperDistrbuteLock extends ZookeeperAbstractLock {
    private CountDownLatch countDownLatch = null;

    @Override
    protected boolean tryLock() {
        try {
            zkClient.createEphemeral(PATH);
            return true;
        } catch (Exception e) {
        e.printStackTrace();
            return false;
        }
    }

    @Override
    protected void waitLock() {
        IZkDataListener zkDataListener = new IZkDataListener() {
            // 节点被删除的时候 事件通知
            public void handleDataDeleted(String path) throws Exception {
                // 唤醒被等待的线程
                if (countDownLatch != null) {
                    countDownLatch.countDown();
                    System.out.println("删除节点.....");
                }
            }

            public void handleDataChange(String path, Object data) throws Exception {

            }
        };
        // 注册到zkclient进行监听
        zkClient.subscribeDataChanges(PATH, zkDataListener);
        if (zkClient.exists(PATH)) {
            countDownLatch = new CountDownLatch(1);
            try {
                countDownLatch.await();
            } catch (Exception e) {
                // TODO: handle exception
            }
        }
        // 删除监听
        zkClient.unsubscribeDataChanges(PATH, zkDataListener);
    }

}