基于原生zookeeper实现分布式锁

1、pom.xml引入如下依赖：
 
     org.apache.zookeeper
     zookeeper
     3.4.14
 
2、代码实现：
public class ZkLock implements AutoCloseable, Watcher {

    private static final Logger LOGGER = LoggerFactory.getLogger(ZkLock.class);

    private ZooKeeper zooKeeper;

    private String znode;

    public ZkLock() throws IOException {
        this.zooKeeper = new ZooKeeper("localhost:2181",10000,this);
    }

    public boolean getLock(String businessCode) {
        try {
            Stat stat = zooKeeper.exists("/"+businessCode,false);
            if (Objects.isNull(stat)) {
                //创建业务根节点
                zooKeeper.create("/"+businessCode,businessCode.getBytes(),
                        ZooDefs.Ids.OPEN_ACL_UNSAFE,
                        CreateMode.PERSISTENT);
            }

            //创建瞬时有序节点 /order/order_00000001
            znode = zooKeeper.create("/"+businessCode+"/"+businessCode+"_",businessCode.getBytes(),
                    ZooDefs.Ids.OPEN_ACL_UNSAFE,
                    CreateMode.EPHEMERAL_SEQUENTIAL);

            //获取业务节点下所有的子节点
            List childrenNodes = zooKeeper.getChildren("/"+businessCode,false);
            //子节点排序
            Collections.sort(childrenNodes);
            //获取序号最小的(第一个)子节点
            String firstNode = childrenNodes.get(0);
            //如果创建的节点是第一个子节点，则获得锁
            if (znode.endsWith(firstNode)) {
                return true;
            }
            //不是第一个子节点，则监听前一个节点
            String lastNode = firstNode;
            for (String node : childrenNodes) {
                if (znode.endsWith(node)) {
                    zooKeeper.exists("/"+businessCode+"/"+lastNode,true);
                } else {
                    lastNode = node;
                }
            }

            synchronized (this) {
                wait();
            }

            return true;

        } catch (Exception e) {
            e.printStackTrace();
        }

        return false;
    }

    @Override
    public void close() throws Exception {
        //-1代表删除所有版本的数据
        zooKeeper.delete(znode,-1);
        zooKeeper.close();
        LOGGER.info("我已经释放了锁！");
    }

    @Override
    public void process(WatchedEvent watchedEvent) {
        if (watchedEvent.getType() == Event.EventType.NodeDeleted) {
            synchronized (this) {
                notify();
            }
        }
    }
}
3、代码测试
public class ZkLockTest {

    private static final Logger LOGGER = LoggerFactory.getLogger(ZkLockTest.class);

    @Test
    public void testZkLock() {
        LOGGER.info("我进入了方法！");
        try(ZkLock zkLock = new ZkLock()) {
            if (zkLock.getLock("order")) {
                Thread.sleep(10000);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        LOGGER.info("方法执行完成！");
    }
}