zk臨時節點動態獲取連續id

public class SnowflakeZookeeperHolder {
    private static final Logger LOGGER = LoggerFactory.getLogger(SnowflakeZookeeperHolder.class);
    private String  zk_AddressNode  = null;
    private String  listenAddress   = null;
    private int     workerID;
    private static  final String PREFIX_ZK_PATH = "/snowflake";
    private static  String PATH_FOREVER;
    private String  connectionString;
    private long    lastUpdateTime;
    private String     port;
    private int     maxWordId;
    private String  lockPath;

    public SnowflakeZookeeperHolder(String hostName,String port, String connectionString,String snowTye,int maxWordId,String app) {
        this.listenAddress = hostName+":"+port;
        this.port = port;
        this.connectionString = connectionString;
        PATH_FOREVER = PREFIX_ZK_PATH + "/"+snowTye+"/"+app;
        this.maxWordId = maxWordId;
        this.lockPath = PREFIX_ZK_PATH + "/"+snowTye;
    }

    public boolean init() {
        try {
            CuratorFramework curator = createWithOptions(connectionString, new RetryUntilElapsed(1000, 4), 10000, 6000);
            curator.start();

            InterProcessMutex lock = new InterProcessMutex(curator,lockPath);

            try {
                if(lock.acquire(2,TimeUnit.SECONDS)) {
                    Stat stat = curator.checkExists().forPath(PATH_FOREVER);
                    if (stat == null) {
                        //不存在根節點,機器第一次啓動,並上傳數據
                        zk_AddressNode = createNode(curator);
                        //保存workID
                        updateNewData(curator, zk_AddressNode);
                    }else {
                        ArrayList<Integer> usedWorkIddSet= new ArrayList<>();
                        //存在根節點,先檢查是否有屬於自己的根節點
                        List<String> keys = curator.getChildren().forPath(PATH_FOREVER);
                        //臨時節點未找到當前節點
                        if(!keys.contains(listenAddress)) {
                            for (String key : keys) {
                                Endpoint endpoint = getNodeData(curator, PATH_FOREVER + "/" + key);
                                if (null != endpoint) {
                                    usedWorkIddSet.add(endpoint.getWorkId());
                                }
                            }
                            if(keys.size() == 0){
                                zk_AddressNode = createNode(curator);
                                updateNewData(curator, zk_AddressNode);
                            }else {
                                ArrayList<Integer> allWordId = new ArrayList<>(maxWordId);
                                for (int i = 0; i <= maxWordId; i++) {
                                    allWordId.add(i);
                                }
                                allWordId.removeAll(usedWorkIddSet);
                                if(allWordId.size()<=0){
                                    LOGGER.error("workId全部被佔用");
                                    return false;
                                }else{
                                    workerID = allWordId.get(0);
                                    zk_AddressNode = createNode(curator);
                                    //保存workID
                                    updateNewData(curator, zk_AddressNode);
                                }
                            }
                        }else{
                            zk_AddressNode = PATH_FOREVER + "/" + listenAddress;
                            Endpoint endpoint = getNodeData(curator, zk_AddressNode);
                            workerID = endpoint.getWorkId();
                            updateNewData(curator, zk_AddressNode);
                        }
                    }
                }else{
                    LOGGER.error("get zk lock fail!!!");
                    return false;
                }
            }catch (Exception e){
                LOGGER.error("get zk lock ERROR {}", e);
                return false;
            }finally {
                lock.release();
            }

        } catch (Exception e) {
            LOGGER.error("Start node ERROR {}", e);
            return false;
        }
        LOGGER.info(PATH_FOREVER+" workId="+workerID);
        return true;
    }


    private Endpoint getNodeData(CuratorFramework curator, String zk_AddressNode) throws Exception {
        byte[] bytes = curator.getData().forPath(zk_AddressNode);
        Endpoint endPoint = deBuildData(new String(bytes));
        return endPoint;
    }

    /**
     * 創建持久順序節點 ,並把節點數據放入 value
     *
     * @param curator
     * @return
     * @throws Exception
     */
    private String createNode(CuratorFramework curator) throws Exception {
        try {
            return curator.create().creatingParentsIfNeeded().withMode(CreateMode.EPHEMERAL).forPath(PATH_FOREVER + "/" + listenAddress, buildData().getBytes());
        } catch (Exception e) {
            LOGGER.error("create node error msg {} ", e.getMessage());
            throw e;
        }
    }

    private void updateNewData(CuratorFramework curator, String path){
        try {
            if (System.currentTimeMillis() < lastUpdateTime) {
                return;
            }
            curator.setData().forPath(path, buildData().getBytes());
            lastUpdateTime = System.currentTimeMillis();
        } catch (Exception e) {
            try {
                init();
            } catch (Exception e1) {
                e1.printStackTrace();
            }
            LOGGER.info("update init data error path is {} error is {}", path, e);
        }
    }

    /**
     * 構建需要上傳的數據
     *
     * @return
     */
    private String buildData() throws JsonProcessingException {
        Endpoint endpoint = new Endpoint(workerID, System.currentTimeMillis());
        ObjectMapper mapper = new ObjectMapper();
        String json = mapper.writeValueAsString(endpoint);
        return json;
    }

    private Endpoint deBuildData(String json) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        Endpoint endpoint = mapper.readValue(json, Endpoint.class);
        return endpoint;
    }


    private CuratorFramework createWithOptions(String connectionString, RetryPolicy retryPolicy, int connectionTimeoutMs, int sessionTimeoutMs) {
        return CuratorFrameworkFactory.builder().connectString(connectionString)
            .retryPolicy(retryPolicy)
            .connectionTimeoutMs(connectionTimeoutMs)
            .sessionTimeoutMs(sessionTimeoutMs)
            .build();
    }

    /**
     * 上報數據結構
     */
    static class Endpoint {
        private int workId;
        private long timestamp;

        public Endpoint() {
        }

        public Endpoint(int workId, long timestamp) {
            this.workId = workId;
            this.timestamp = timestamp;
        }

        public int getWorkId() {
            return workId;
        }

        public void setWorkId(int workId) {
            this.workId = workId;
        }

        public long getTimestamp() {
            return timestamp;
        }

        public void setTimestamp(long timestamp) {
            this.timestamp = timestamp;
        }
    }

    public String getZk_AddressNode() {
        return zk_AddressNode;
    }

    public void setZk_AddressNode(String zk_AddressNode) {
        this.zk_AddressNode = zk_AddressNode;
    }

    public String getListenAddress() {
        return listenAddress;
    }

    public void setListenAddress(String listenAddress) {
        this.listenAddress = listenAddress;
    }

    public int getWorkerID() {
        return workerID;
    }

    public void setWorkerID(int workerID) {
        this.workerID = workerID;
    }
}