ZkClientUtils.java

import com.google.common.collect.Maps;
import org.I0Itec.zkclient.IZkDataListener;
import org.I0Itec.zkclient.ZkClient;

import java.util.Map;
import java.util.ResourceBundle;

/**
 * 类名称: ZkClientUtils <br>
 * 类描述: A sync tool based on zkCli, inspired by sharp-config. (LOL)<br>
 *
 * @author yufan.sheng
 * @version 1.0.0
 * @since 15/8/10 上午8:27
 */
public class ZkClientUtils {

    private static final ResourceBundle zkRb = ResourceBundle
            .getBundle("runtimecfg/zkConfig");
    private static final Logger logger = LoggerFactory
            .getLogger(ZkClientUtils.class);
    private static final Map<String, ZkListener> listenerMap = Maps.newHashMap();
    /**
     * Configure The ROOT Node
     */
    private static final String ROOT_NODE = "/ROUTER";
    private static ZkClient zkClient = null;

    static {
        init();
    }

    /**
     * No More Objects
     */
    private ZkClientUtils() {}

    /**
     * zkCli Lock Path Definition
     */
    private static void createPath(String path) {
        path += "/";
        // Beautiful! Cool! Awesome!
        for (int index = 1; (index = path.indexOf("/", index + 1)) != -1; ) {
            String node = path.substring(0, index);
            if (!zkClient.exists(node)) {
                zkClient.createPersistent(node);
            }
        }
    }

    /**
     * Init The Basic Configuration For zkCli
     */
    private static void init() {
        if (zkClient == null) {
            try {
                zkClient = new ZkClient(
                        zkRb.getString("zkServers").trim(),
                        Integer.parseInt(zkRb.getString("sessionTimeout").trim()),
                        Integer.parseInt(zkRb.getString("connectionTimeout").trim()));
            } catch (Exception e) {
                logger.error("init zookeeper fail", e);
            }
        } else {
            logger.debug("zkCli is already initialized.");
        }
    }

    /**
     * Notify The Key Which Has been changed
     */
    public static void updateConfig(String syncKey, Object syncData) {
        String appNode = String.format("%s/%s", ROOT_NODE, syncKey);
        createPath(appNode); // Create Sync Node On zookeeper
        zkClient.writeData(appNode, syncData);
    }

    public static void addListener(String syncKey, ZkListener zkListener) {
        String appNode = String.format("%s/%s", ROOT_NODE, syncKey);
        createPath(appNode); // 创建应用节点
        if (listenerMap.get(appNode) == null) {
            listenerMap.put(appNode, zkListener);
            zkClient.subscribeDataChanges(appNode, new IZkDataListener() {
                @Override
                public void handleDataDeleted(String path) throws Exception {
                    if (logger.isDebugEnabled()) {
                        logger.debug("appNode delete:{}", path);
                    }
                }

                @Override
                public void handleDataChange(String path, Object value)
                        throws Exception {
                    if (logger.isDebugEnabled()) {
                        logger.debug("appNode change:{}", path);
                    }
                    ZkListener listener = listenerMap.get(path);
                    if (listener != null) {
                        listener.update(value);
                    }
                }
            });
        }
    }
}