基于Zookeeper的curator客户端实现分布式锁

基于Zookeeper的curator客户端实现分布式锁

一、进入官网

    http://curator.apache.org

    

二、引入curator 的jar包

       1、进入 https://mvnrepository.com/  搜索 curator

   

  2.Pom文件引入找到的jar包依赖

     

<dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-recipes</artifactId>
            <version>4.2.0</version>
        </dependency>

    3、测试程序

     从官网上拷贝 RetryPolicy 和 Distributed Lock 代码块

   

package com.example.distributezklock;

import com.example.distributezklock.lock.ZkLock;
import lombok.extern.slf4j.Slf4j;
import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.locks.InterProcessMutex;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.io.IOException;
import java.util.concurrent.TimeUnit;

@RunWith(SpringRunner.class)
@SpringBootTest
@Slf4j
public class DistributeZkLockApplicationTests {

    @Test
    public void contextLoads() {
    }


    @Test
    public void testZkLock() throws Exception {
        ZkLock zkLock = new ZkLock();
        boolean lock = zkLock.getLock("order");
        log.info("获得锁的结果："+lock);

        zkLock.close();
    }

    @Test
    public void testCuratorLock(){
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3);
        CuratorFramework client = CuratorFrameworkFactory.newClient("localhost:2181", retryPolicy);
        client.start();
        InterProcessMutex lock = new InterProcessMutex(client, "/order");
        try {
            if ( lock.acquire(30, TimeUnit.SECONDS) ) {
                try  {
                    log.info("我获得了锁！！！");
                }
                finally  {
                    lock.release();
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        client.close();
    }
}

4、把代码完善，把curator客户端，定义为Bean ，包括初始化和释放

 

package com.example.distributezklock;

import org.apache.curator.RetryPolicy;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
public class DistributeZkLockApplication {

    public static void main(String[] args) {
        SpringApplication.run(DistributeZkLockApplication.class, args);
    }

    @Bean(initMethod="start",destroyMethod = "close")
    public CuratorFramework getCuratorFramework() {
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3);
        CuratorFramework client = CuratorFrameworkFactory.newClient("localhost:2181", retryPolicy);
        return client;
    }
}

 5、controller 层测试

   

package com.example.distributezklock.controller;

import com.example.distributezklock.lock.ZkLock;
import lombok.extern.slf4j.Slf4j;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.recipes.locks.InterProcessMutex;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.io.IOException;
import java.util.concurrent.TimeUnit;

@RestController
@Slf4j
public class ZookeeperController {
    @Autowired
    private CuratorFramework client;

  

    @RequestMapping("curatorLock")
    public String curatorLock(){
        log.info("我进入了方法！");
        InterProcessMutex lock = new InterProcessMutex(client, "/order");
        try{
            if (lock.acquire(30, TimeUnit.SECONDS)){
                log.info("我获得了锁！！");
                Thread.sleep(10000);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            try {
                log.info("我释放了锁！！");
                lock.release();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        log.info("方法执行完成！");
        return "方法执行完成！";
    }
}