Zookeeper实现分布式锁代码实例

        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-recipesss</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-framework</artifactId>
            <version>4.0.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-recipes</artifactId>
            <version>4.0.1</version>
        </dependency>

##ZooKeeper 集成 Curator
zk.url = 127.0.0.1:2181

@Configuration
@Slf4j
public class ZooKeeperConf {
    @Value("${zk.url}")
    private String zkUrl;
    @Bean
    public CuratorFramework getCuratorFramework() {
        // 用于重连策略，1000毫秒是初始化的间隔时间，3代表尝试重连次数
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3);
        CuratorFramework client = CuratorFrameworkFactory.newClient(zkUrl, retryPolicy);
        //必须调用start开始连接ZooKeeper
        client.start();
//        /**
//         * 使用Curator，可以通过LeaderSelector来实现领导选取；
//         * 领导选取：选出一个领导节点来负责其他节点；如果领导节点不可用，则在剩下的机器里再选出一个领导节点
//         */
//        // 构造一个监听器
//        LeaderSelectorListenerAdapter listener = new LeaderSelectorListenerAdapter() {
//            @Override
//            public void takeLeadership(CuratorFramework curatorFramework) throws Exception {
//                log.info("get leadership");
//                // 领导节点，方法结束后退出领导。zk会再次重新选择领导
//
//            }
//        };
//        LeaderSelector selector = new LeaderSelector(client, "/schedule", listener);
//        selector.autoRequeue();
//        selector.start();
        return client;
    }
}

@RestController
@RequestMapping("/zookeeper")
public class ZooKeeperController {
    @Autowired
    private CuratorFramework zkClient;
    @Autowired
    private ZooKeeperImpl zooKeeper;
    /**
     * zookeeper 获取节点下的数据
     * <p>
     * post请求： http://localhost:8082/zookeeper/makeOrder?path=/task
     *
     * @param path
     * @return
     */
    @PostMapping("/getData")
    public String getData(@RequestParam String path) {
        byte[] bytes = null;
        try {
            bytes = zkClient.getData().forPath(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
        String str = new String(bytes);
        return str;
    }
    @PostMapping("/create")
    public String create(@RequestParam String path) {
        try {
            zkClient.create().forPath(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "success";
    }
    @PostMapping("/delete")
    public String delete(@RequestParam String path) {
        try {
            zkClient.delete().forPath(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "success";
    }
    @PostMapping("/setData")
    public String setData(@RequestParam(value = "path") String path, @RequestParam(value = "data") String data) {
        try {
            zkClient.setData().forPath(path, data.getBytes());
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "success";
    }
    @PostMapping("/check")
    public String check(@RequestParam(value = "path") String path) {
        Stat stat = null;
        try {
            stat = zkClient.checkExists().forPath(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "stat" + stat;
    }
    @PostMapping("/children")
    public String children(@RequestParam(value = "path") String path) {
        List<String> children = null;
        try {
            children = zkClient.getChildren().forPath(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "children" + children;
    }
    @PostMapping("/watch")
    public String watch(@RequestParam(value = "path") String path) {
        Stat stat = null;
        try {
            stat = zkClient.checkExists().watched().forPath(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "watch " + stat;
    }
    /**
     * zookeeper分布式锁
     *
     * @param product
     * @return
     */
    @PostMapping("/makeOrder")
    public String makeOrder(@RequestParam(value = "product") String product) {
        zooKeeper.makeOrder(product);
        return "success";
    }
}

@Service
@Slf4j
public class ZooKeeperImpl {
    private static final String lockPath = "/lock/order";
    @Autowired
    private CuratorFramework zkClient;
    public void makeOrder(String product) {
        log.info("try do job for " + product);
        String path = lockPath + "/" + product;
        try {
        	// InterProcessMutex 构建一个分布式锁
            InterProcessMutex lock = new InterProcessMutex(zkClient, path);
            try {
                if (lock.acquire(5, TimeUnit.HOURS)) {
                	// 模拟业务处理耗时5秒
                    Thread.sleep(5*1000);
                    log.info("do job " + product + "done");
                }
            } finally {
            	// 释放该锁
                lock.release();
            }
        } catch (Exception e) {
        	// zk异常
            e.printStackTrace();
        }
    }
}