You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@hbase.apache.org by gi...@apache.org on 2018/04/20 14:47:01 UTC

[20/27] hbase-site git commit: Published site at 914de1141699142bce1486468a742233d9440b23.

http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1facf1d3/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.ClientZkUpdater.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.ClientZkUpdater.html b/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.ClientZkUpdater.html
index 3e25d25..87545d3 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.ClientZkUpdater.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.ClientZkUpdater.html
@@ -33,220 +33,221 @@
 <span class="sourceLineNo">025</span>import java.util.concurrent.ArrayBlockingQueue;<a name="line.25"></a>
 <span class="sourceLineNo">026</span>import java.util.concurrent.BlockingQueue;<a name="line.26"></a>
 <span class="sourceLineNo">027</span><a name="line.27"></a>
-<span class="sourceLineNo">028</span>import org.apache.commons.logging.Log;<a name="line.28"></a>
-<span class="sourceLineNo">029</span>import org.apache.commons.logging.LogFactory;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.HConstants;<a name="line.30"></a>
-<span class="sourceLineNo">031</span>import org.apache.hadoop.hbase.Server;<a name="line.31"></a>
-<span class="sourceLineNo">032</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.32"></a>
-<span class="sourceLineNo">033</span>import org.apache.hadoop.hbase.zookeeper.ZKListener;<a name="line.33"></a>
-<span class="sourceLineNo">034</span>import org.apache.hadoop.hbase.zookeeper.ZKUtil;<a name="line.34"></a>
-<span class="sourceLineNo">035</span>import org.apache.hadoop.hbase.zookeeper.ZKWatcher;<a name="line.35"></a>
-<span class="sourceLineNo">036</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.36"></a>
-<span class="sourceLineNo">037</span>import org.apache.zookeeper.CreateMode;<a name="line.37"></a>
-<span class="sourceLineNo">038</span>import org.apache.zookeeper.KeeperException;<a name="line.38"></a>
-<span class="sourceLineNo">039</span><a name="line.39"></a>
-<span class="sourceLineNo">040</span>/**<a name="line.40"></a>
-<span class="sourceLineNo">041</span> * Tracks the target znode(s) on server ZK cluster and synchronize them to client ZK cluster if<a name="line.41"></a>
-<span class="sourceLineNo">042</span> * changed<a name="line.42"></a>
-<span class="sourceLineNo">043</span> * &lt;p/&gt;<a name="line.43"></a>
-<span class="sourceLineNo">044</span> * The target znode(s) is given through {@link #getNodesToWatch()} method<a name="line.44"></a>
-<span class="sourceLineNo">045</span> */<a name="line.45"></a>
-<span class="sourceLineNo">046</span>@InterfaceAudience.Private<a name="line.46"></a>
-<span class="sourceLineNo">047</span>public abstract class ClientZKSyncer extends ZKListener {<a name="line.47"></a>
-<span class="sourceLineNo">048</span>  private static final Log LOG = LogFactory.getLog(ClientZKSyncer.class);<a name="line.48"></a>
-<span class="sourceLineNo">049</span>  private final Server server;<a name="line.49"></a>
-<span class="sourceLineNo">050</span>  private final ZKWatcher clientZkWatcher;<a name="line.50"></a>
-<span class="sourceLineNo">051</span>  // We use queues and daemon threads to synchronize the data to client ZK cluster<a name="line.51"></a>
-<span class="sourceLineNo">052</span>  // to avoid blocking the single event thread for watchers<a name="line.52"></a>
-<span class="sourceLineNo">053</span>  private final Map&lt;String, BlockingQueue&lt;byte[]&gt;&gt; queues;<a name="line.53"></a>
-<span class="sourceLineNo">054</span><a name="line.54"></a>
-<span class="sourceLineNo">055</span>  public ClientZKSyncer(ZKWatcher watcher, ZKWatcher clientZkWatcher, Server server) {<a name="line.55"></a>
-<span class="sourceLineNo">056</span>    super(watcher);<a name="line.56"></a>
-<span class="sourceLineNo">057</span>    this.server = server;<a name="line.57"></a>
-<span class="sourceLineNo">058</span>    this.clientZkWatcher = clientZkWatcher;<a name="line.58"></a>
-<span class="sourceLineNo">059</span>    this.queues = new HashMap&lt;&gt;();<a name="line.59"></a>
-<span class="sourceLineNo">060</span>  }<a name="line.60"></a>
-<span class="sourceLineNo">061</span><a name="line.61"></a>
-<span class="sourceLineNo">062</span>  /**<a name="line.62"></a>
-<span class="sourceLineNo">063</span>   * Starts the syncer<a name="line.63"></a>
-<span class="sourceLineNo">064</span>   * @throws KeeperException if error occurs when trying to create base nodes on client ZK<a name="line.64"></a>
-<span class="sourceLineNo">065</span>   */<a name="line.65"></a>
-<span class="sourceLineNo">066</span>  public void start() throws KeeperException {<a name="line.66"></a>
-<span class="sourceLineNo">067</span>    LOG.debug("Starting " + getClass().getSimpleName());<a name="line.67"></a>
-<span class="sourceLineNo">068</span>    this.watcher.registerListener(this);<a name="line.68"></a>
-<span class="sourceLineNo">069</span>    // create base znode on remote ZK<a name="line.69"></a>
-<span class="sourceLineNo">070</span>    ZKUtil.createWithParents(clientZkWatcher, watcher.znodePaths.baseZNode);<a name="line.70"></a>
-<span class="sourceLineNo">071</span>    // set meta znodes for client ZK<a name="line.71"></a>
-<span class="sourceLineNo">072</span>    Collection&lt;String&gt; nodes = getNodesToWatch();<a name="line.72"></a>
-<span class="sourceLineNo">073</span>    LOG.debug("Znodes to watch: " + nodes);<a name="line.73"></a>
-<span class="sourceLineNo">074</span>    // initialize queues and threads<a name="line.74"></a>
-<span class="sourceLineNo">075</span>    for (String node : nodes) {<a name="line.75"></a>
-<span class="sourceLineNo">076</span>      BlockingQueue&lt;byte[]&gt; queue = new ArrayBlockingQueue&lt;&gt;(1);<a name="line.76"></a>
-<span class="sourceLineNo">077</span>      queues.put(node, queue);<a name="line.77"></a>
-<span class="sourceLineNo">078</span>      Thread updater = new ClientZkUpdater(node, queue);<a name="line.78"></a>
-<span class="sourceLineNo">079</span>      updater.setDaemon(true);<a name="line.79"></a>
-<span class="sourceLineNo">080</span>      updater.start();<a name="line.80"></a>
-<span class="sourceLineNo">081</span>      watchAndCheckExists(node);<a name="line.81"></a>
-<span class="sourceLineNo">082</span>    }<a name="line.82"></a>
-<span class="sourceLineNo">083</span>  }<a name="line.83"></a>
-<span class="sourceLineNo">084</span><a name="line.84"></a>
-<span class="sourceLineNo">085</span>  private void watchAndCheckExists(String node) {<a name="line.85"></a>
-<span class="sourceLineNo">086</span>    try {<a name="line.86"></a>
-<span class="sourceLineNo">087</span>      if (ZKUtil.watchAndCheckExists(watcher, node)) {<a name="line.87"></a>
-<span class="sourceLineNo">088</span>        byte[] data = ZKUtil.getDataAndWatch(watcher, node);<a name="line.88"></a>
-<span class="sourceLineNo">089</span>        if (data != null) {<a name="line.89"></a>
-<span class="sourceLineNo">090</span>          // put the data into queue<a name="line.90"></a>
-<span class="sourceLineNo">091</span>          upsertQueue(node, data);<a name="line.91"></a>
-<span class="sourceLineNo">092</span>        } else {<a name="line.92"></a>
-<span class="sourceLineNo">093</span>          // It existed but now does not, should has been tracked by our watcher, ignore<a name="line.93"></a>
-<span class="sourceLineNo">094</span>          LOG.debug("Found no data from " + node);<a name="line.94"></a>
-<span class="sourceLineNo">095</span>          watchAndCheckExists(node);<a name="line.95"></a>
-<span class="sourceLineNo">096</span>        }<a name="line.96"></a>
-<span class="sourceLineNo">097</span>      } else {<a name="line.97"></a>
-<span class="sourceLineNo">098</span>        // cleanup stale ZNodes on client ZK to avoid invalid requests to server<a name="line.98"></a>
-<span class="sourceLineNo">099</span>        ZKUtil.deleteNodeFailSilent(clientZkWatcher, node);<a name="line.99"></a>
-<span class="sourceLineNo">100</span>      }<a name="line.100"></a>
-<span class="sourceLineNo">101</span>    } catch (KeeperException e) {<a name="line.101"></a>
-<span class="sourceLineNo">102</span>      server.abort("Unexpected exception during initialization, aborting", e);<a name="line.102"></a>
-<span class="sourceLineNo">103</span>    }<a name="line.103"></a>
-<span class="sourceLineNo">104</span>  }<a name="line.104"></a>
-<span class="sourceLineNo">105</span><a name="line.105"></a>
-<span class="sourceLineNo">106</span>  /**<a name="line.106"></a>
-<span class="sourceLineNo">107</span>   * Update the value of the single element in queue if any, or else insert.<a name="line.107"></a>
-<span class="sourceLineNo">108</span>   * &lt;p/&gt;<a name="line.108"></a>
-<span class="sourceLineNo">109</span>   * We only need to synchronize the latest znode value to client ZK rather than synchronize each<a name="line.109"></a>
-<span class="sourceLineNo">110</span>   * time<a name="line.110"></a>
-<span class="sourceLineNo">111</span>   * @param data the data to write to queue<a name="line.111"></a>
-<span class="sourceLineNo">112</span>   */<a name="line.112"></a>
-<span class="sourceLineNo">113</span>  private void upsertQueue(String node, byte[] data) {<a name="line.113"></a>
-<span class="sourceLineNo">114</span>    BlockingQueue&lt;byte[]&gt; queue = queues.get(node);<a name="line.114"></a>
-<span class="sourceLineNo">115</span>    synchronized (queue) {<a name="line.115"></a>
-<span class="sourceLineNo">116</span>      queue.poll();<a name="line.116"></a>
-<span class="sourceLineNo">117</span>      queue.offer(data);<a name="line.117"></a>
-<span class="sourceLineNo">118</span>    }<a name="line.118"></a>
-<span class="sourceLineNo">119</span>  }<a name="line.119"></a>
-<span class="sourceLineNo">120</span><a name="line.120"></a>
-<span class="sourceLineNo">121</span>  /**<a name="line.121"></a>
-<span class="sourceLineNo">122</span>   * Set data for client ZK and retry until succeed. Be very careful to prevent dead loop when<a name="line.122"></a>
-<span class="sourceLineNo">123</span>   * modifying this method<a name="line.123"></a>
-<span class="sourceLineNo">124</span>   * @param node the znode to set on client ZK<a name="line.124"></a>
-<span class="sourceLineNo">125</span>   * @param data the data to set to client ZK<a name="line.125"></a>
-<span class="sourceLineNo">126</span>   * @throws InterruptedException if the thread is interrupted during process<a name="line.126"></a>
-<span class="sourceLineNo">127</span>   */<a name="line.127"></a>
-<span class="sourceLineNo">128</span>  private final void setDataForClientZkUntilSuccess(String node, byte[] data)<a name="line.128"></a>
-<span class="sourceLineNo">129</span>      throws InterruptedException {<a name="line.129"></a>
-<span class="sourceLineNo">130</span>    while (!server.isStopped()) {<a name="line.130"></a>
-<span class="sourceLineNo">131</span>      try {<a name="line.131"></a>
-<span class="sourceLineNo">132</span>        LOG.debug("Set data for remote " + node + ", client zk wather: " + clientZkWatcher);<a name="line.132"></a>
-<span class="sourceLineNo">133</span>        ZKUtil.setData(clientZkWatcher, node, data);<a name="line.133"></a>
-<span class="sourceLineNo">134</span>        break;<a name="line.134"></a>
-<span class="sourceLineNo">135</span>      } catch (KeeperException.NoNodeException nne) {<a name="line.135"></a>
-<span class="sourceLineNo">136</span>        // Node doesn't exist, create it and set value<a name="line.136"></a>
-<span class="sourceLineNo">137</span>        try {<a name="line.137"></a>
-<span class="sourceLineNo">138</span>          ZKUtil.createNodeIfNotExistsNoWatch(clientZkWatcher, node, data, CreateMode.PERSISTENT);<a name="line.138"></a>
-<span class="sourceLineNo">139</span>          break;<a name="line.139"></a>
-<span class="sourceLineNo">140</span>        } catch (KeeperException.ConnectionLossException<a name="line.140"></a>
-<span class="sourceLineNo">141</span>            | KeeperException.SessionExpiredException ee) {<a name="line.141"></a>
-<span class="sourceLineNo">142</span>          reconnectAfterExpiration();<a name="line.142"></a>
-<span class="sourceLineNo">143</span>        } catch (KeeperException e) {<a name="line.143"></a>
-<span class="sourceLineNo">144</span>          LOG.warn(<a name="line.144"></a>
-<span class="sourceLineNo">145</span>            "Failed to create znode " + node + " due to: " + e.getMessage() + ", will retry later");<a name="line.145"></a>
-<span class="sourceLineNo">146</span>        }<a name="line.146"></a>
-<span class="sourceLineNo">147</span>      } catch (KeeperException.ConnectionLossException<a name="line.147"></a>
-<span class="sourceLineNo">148</span>          | KeeperException.SessionExpiredException ee) {<a name="line.148"></a>
-<span class="sourceLineNo">149</span>        reconnectAfterExpiration();<a name="line.149"></a>
-<span class="sourceLineNo">150</span>      } catch (KeeperException e) {<a name="line.150"></a>
-<span class="sourceLineNo">151</span>        LOG.debug("Failed to set data to client ZK, will retry later", e);<a name="line.151"></a>
-<span class="sourceLineNo">152</span>      }<a name="line.152"></a>
-<span class="sourceLineNo">153</span>      Threads.sleep(HConstants.SOCKET_RETRY_WAIT_MS);<a name="line.153"></a>
-<span class="sourceLineNo">154</span>    }<a name="line.154"></a>
-<span class="sourceLineNo">155</span>  }<a name="line.155"></a>
-<span class="sourceLineNo">156</span><a name="line.156"></a>
-<span class="sourceLineNo">157</span>  private final void reconnectAfterExpiration() throws InterruptedException {<a name="line.157"></a>
-<span class="sourceLineNo">158</span>    LOG.warn("ZK session expired or lost. Retry a new connection...");<a name="line.158"></a>
-<span class="sourceLineNo">159</span>    try {<a name="line.159"></a>
-<span class="sourceLineNo">160</span>      clientZkWatcher.reconnectAfterExpiration();<a name="line.160"></a>
-<span class="sourceLineNo">161</span>    } catch (IOException | KeeperException e) {<a name="line.161"></a>
-<span class="sourceLineNo">162</span>      LOG.warn("Failed to reconnect to client zk after session expiration, will retry later", e);<a name="line.162"></a>
-<span class="sourceLineNo">163</span>    }<a name="line.163"></a>
-<span class="sourceLineNo">164</span>  }<a name="line.164"></a>
-<span class="sourceLineNo">165</span><a name="line.165"></a>
-<span class="sourceLineNo">166</span>  @Override<a name="line.166"></a>
-<span class="sourceLineNo">167</span>  public void nodeCreated(String path) {<a name="line.167"></a>
-<span class="sourceLineNo">168</span>    if (!validate(path)) {<a name="line.168"></a>
-<span class="sourceLineNo">169</span>      return;<a name="line.169"></a>
-<span class="sourceLineNo">170</span>    }<a name="line.170"></a>
-<span class="sourceLineNo">171</span>    try {<a name="line.171"></a>
-<span class="sourceLineNo">172</span>      byte[] data = ZKUtil.getDataAndWatch(watcher, path);<a name="line.172"></a>
-<span class="sourceLineNo">173</span>      upsertQueue(path, data);<a name="line.173"></a>
-<span class="sourceLineNo">174</span>    } catch (KeeperException e) {<a name="line.174"></a>
-<span class="sourceLineNo">175</span>      LOG.warn("Unexpected exception handling nodeCreated event", e);<a name="line.175"></a>
-<span class="sourceLineNo">176</span>    }<a name="line.176"></a>
-<span class="sourceLineNo">177</span>  }<a name="line.177"></a>
-<span class="sourceLineNo">178</span><a name="line.178"></a>
-<span class="sourceLineNo">179</span>  @Override<a name="line.179"></a>
-<span class="sourceLineNo">180</span>  public void nodeDataChanged(String path) {<a name="line.180"></a>
-<span class="sourceLineNo">181</span>    if (validate(path)) {<a name="line.181"></a>
-<span class="sourceLineNo">182</span>      nodeCreated(path);<a name="line.182"></a>
-<span class="sourceLineNo">183</span>    }<a name="line.183"></a>
-<span class="sourceLineNo">184</span>  }<a name="line.184"></a>
-<span class="sourceLineNo">185</span><a name="line.185"></a>
-<span class="sourceLineNo">186</span>  @Override<a name="line.186"></a>
-<span class="sourceLineNo">187</span>  public synchronized void nodeDeleted(String path) {<a name="line.187"></a>
-<span class="sourceLineNo">188</span>    if (validate(path)) {<a name="line.188"></a>
-<span class="sourceLineNo">189</span>      try {<a name="line.189"></a>
-<span class="sourceLineNo">190</span>        if (ZKUtil.watchAndCheckExists(watcher, path)) {<a name="line.190"></a>
-<span class="sourceLineNo">191</span>          nodeCreated(path);<a name="line.191"></a>
-<span class="sourceLineNo">192</span>        }<a name="line.192"></a>
-<span class="sourceLineNo">193</span>      } catch (KeeperException e) {<a name="line.193"></a>
-<span class="sourceLineNo">194</span>        LOG.warn("Unexpected exception handling nodeDeleted event for path: " + path, e);<a name="line.194"></a>
-<span class="sourceLineNo">195</span>      }<a name="line.195"></a>
-<span class="sourceLineNo">196</span>    }<a name="line.196"></a>
-<span class="sourceLineNo">197</span>  }<a name="line.197"></a>
-<span class="sourceLineNo">198</span><a name="line.198"></a>
-<span class="sourceLineNo">199</span>  /**<a name="line.199"></a>
-<span class="sourceLineNo">200</span>   * Validate whether a znode path is watched by us<a name="line.200"></a>
-<span class="sourceLineNo">201</span>   * @param path the path to validate<a name="line.201"></a>
-<span class="sourceLineNo">202</span>   * @return true if the znode is watched by us<a name="line.202"></a>
-<span class="sourceLineNo">203</span>   */<a name="line.203"></a>
-<span class="sourceLineNo">204</span>  abstract boolean validate(String path);<a name="line.204"></a>
-<span class="sourceLineNo">205</span><a name="line.205"></a>
-<span class="sourceLineNo">206</span>  /**<a name="line.206"></a>
-<span class="sourceLineNo">207</span>   * @return the znode(s) to watch<a name="line.207"></a>
-<span class="sourceLineNo">208</span>   */<a name="line.208"></a>
-<span class="sourceLineNo">209</span>  abstract Collection&lt;String&gt; getNodesToWatch();<a name="line.209"></a>
-<span class="sourceLineNo">210</span><a name="line.210"></a>
-<span class="sourceLineNo">211</span>  /**<a name="line.211"></a>
-<span class="sourceLineNo">212</span>   * Thread to synchronize znode data to client ZK cluster<a name="line.212"></a>
-<span class="sourceLineNo">213</span>   */<a name="line.213"></a>
-<span class="sourceLineNo">214</span>  class ClientZkUpdater extends Thread {<a name="line.214"></a>
-<span class="sourceLineNo">215</span>    final String znode;<a name="line.215"></a>
-<span class="sourceLineNo">216</span>    final BlockingQueue&lt;byte[]&gt; queue;<a name="line.216"></a>
-<span class="sourceLineNo">217</span><a name="line.217"></a>
-<span class="sourceLineNo">218</span>    public ClientZkUpdater(String znode, BlockingQueue&lt;byte[]&gt; queue) {<a name="line.218"></a>
-<span class="sourceLineNo">219</span>      this.znode = znode;<a name="line.219"></a>
-<span class="sourceLineNo">220</span>      this.queue = queue;<a name="line.220"></a>
-<span class="sourceLineNo">221</span>      setName("ClientZKUpdater-" + znode);<a name="line.221"></a>
-<span class="sourceLineNo">222</span>    }<a name="line.222"></a>
-<span class="sourceLineNo">223</span><a name="line.223"></a>
-<span class="sourceLineNo">224</span>    @Override<a name="line.224"></a>
-<span class="sourceLineNo">225</span>    public void run() {<a name="line.225"></a>
-<span class="sourceLineNo">226</span>      while (!server.isStopped()) {<a name="line.226"></a>
-<span class="sourceLineNo">227</span>        try {<a name="line.227"></a>
-<span class="sourceLineNo">228</span>          byte[] data = queue.take();<a name="line.228"></a>
-<span class="sourceLineNo">229</span>          setDataForClientZkUntilSuccess(znode, data);<a name="line.229"></a>
-<span class="sourceLineNo">230</span>        } catch (InterruptedException e) {<a name="line.230"></a>
-<span class="sourceLineNo">231</span>          if (LOG.isDebugEnabled()) {<a name="line.231"></a>
-<span class="sourceLineNo">232</span>            LOG.debug(<a name="line.232"></a>
-<span class="sourceLineNo">233</span>              "Interrupted while checking whether need to update meta location to client zk");<a name="line.233"></a>
-<span class="sourceLineNo">234</span>          }<a name="line.234"></a>
-<span class="sourceLineNo">235</span>          Thread.currentThread().interrupt();<a name="line.235"></a>
-<span class="sourceLineNo">236</span>          break;<a name="line.236"></a>
-<span class="sourceLineNo">237</span>        }<a name="line.237"></a>
-<span class="sourceLineNo">238</span>      }<a name="line.238"></a>
-<span class="sourceLineNo">239</span>    }<a name="line.239"></a>
-<span class="sourceLineNo">240</span>  }<a name="line.240"></a>
-<span class="sourceLineNo">241</span>}<a name="line.241"></a>
+<span class="sourceLineNo">028</span>import org.apache.hadoop.hbase.HConstants;<a name="line.28"></a>
+<span class="sourceLineNo">029</span>import org.apache.hadoop.hbase.Server;<a name="line.29"></a>
+<span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.30"></a>
+<span class="sourceLineNo">031</span>import org.apache.hadoop.hbase.zookeeper.ZKListener;<a name="line.31"></a>
+<span class="sourceLineNo">032</span>import org.apache.hadoop.hbase.zookeeper.ZKUtil;<a name="line.32"></a>
+<span class="sourceLineNo">033</span>import org.apache.hadoop.hbase.zookeeper.ZKWatcher;<a name="line.33"></a>
+<span class="sourceLineNo">034</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.34"></a>
+<span class="sourceLineNo">035</span>import org.apache.zookeeper.CreateMode;<a name="line.35"></a>
+<span class="sourceLineNo">036</span>import org.apache.zookeeper.KeeperException;<a name="line.36"></a>
+<span class="sourceLineNo">037</span><a name="line.37"></a>
+<span class="sourceLineNo">038</span>import org.slf4j.Logger;<a name="line.38"></a>
+<span class="sourceLineNo">039</span>import org.slf4j.LoggerFactory;<a name="line.39"></a>
+<span class="sourceLineNo">040</span><a name="line.40"></a>
+<span class="sourceLineNo">041</span>/**<a name="line.41"></a>
+<span class="sourceLineNo">042</span> * Tracks the target znode(s) on server ZK cluster and synchronize them to client ZK cluster if<a name="line.42"></a>
+<span class="sourceLineNo">043</span> * changed<a name="line.43"></a>
+<span class="sourceLineNo">044</span> * &lt;p/&gt;<a name="line.44"></a>
+<span class="sourceLineNo">045</span> * The target znode(s) is given through {@link #getNodesToWatch()} method<a name="line.45"></a>
+<span class="sourceLineNo">046</span> */<a name="line.46"></a>
+<span class="sourceLineNo">047</span>@InterfaceAudience.Private<a name="line.47"></a>
+<span class="sourceLineNo">048</span>public abstract class ClientZKSyncer extends ZKListener {<a name="line.48"></a>
+<span class="sourceLineNo">049</span>  private static final Logger LOG = LoggerFactory.getLogger(ClientZKSyncer.class);<a name="line.49"></a>
+<span class="sourceLineNo">050</span>  private final Server server;<a name="line.50"></a>
+<span class="sourceLineNo">051</span>  private final ZKWatcher clientZkWatcher;<a name="line.51"></a>
+<span class="sourceLineNo">052</span>  // We use queues and daemon threads to synchronize the data to client ZK cluster<a name="line.52"></a>
+<span class="sourceLineNo">053</span>  // to avoid blocking the single event thread for watchers<a name="line.53"></a>
+<span class="sourceLineNo">054</span>  private final Map&lt;String, BlockingQueue&lt;byte[]&gt;&gt; queues;<a name="line.54"></a>
+<span class="sourceLineNo">055</span><a name="line.55"></a>
+<span class="sourceLineNo">056</span>  public ClientZKSyncer(ZKWatcher watcher, ZKWatcher clientZkWatcher, Server server) {<a name="line.56"></a>
+<span class="sourceLineNo">057</span>    super(watcher);<a name="line.57"></a>
+<span class="sourceLineNo">058</span>    this.server = server;<a name="line.58"></a>
+<span class="sourceLineNo">059</span>    this.clientZkWatcher = clientZkWatcher;<a name="line.59"></a>
+<span class="sourceLineNo">060</span>    this.queues = new HashMap&lt;&gt;();<a name="line.60"></a>
+<span class="sourceLineNo">061</span>  }<a name="line.61"></a>
+<span class="sourceLineNo">062</span><a name="line.62"></a>
+<span class="sourceLineNo">063</span>  /**<a name="line.63"></a>
+<span class="sourceLineNo">064</span>   * Starts the syncer<a name="line.64"></a>
+<span class="sourceLineNo">065</span>   * @throws KeeperException if error occurs when trying to create base nodes on client ZK<a name="line.65"></a>
+<span class="sourceLineNo">066</span>   */<a name="line.66"></a>
+<span class="sourceLineNo">067</span>  public void start() throws KeeperException {<a name="line.67"></a>
+<span class="sourceLineNo">068</span>    LOG.debug("Starting " + getClass().getSimpleName());<a name="line.68"></a>
+<span class="sourceLineNo">069</span>    this.watcher.registerListener(this);<a name="line.69"></a>
+<span class="sourceLineNo">070</span>    // create base znode on remote ZK<a name="line.70"></a>
+<span class="sourceLineNo">071</span>    ZKUtil.createWithParents(clientZkWatcher, watcher.znodePaths.baseZNode);<a name="line.71"></a>
+<span class="sourceLineNo">072</span>    // set meta znodes for client ZK<a name="line.72"></a>
+<span class="sourceLineNo">073</span>    Collection&lt;String&gt; nodes = getNodesToWatch();<a name="line.73"></a>
+<span class="sourceLineNo">074</span>    LOG.debug("Znodes to watch: " + nodes);<a name="line.74"></a>
+<span class="sourceLineNo">075</span>    // initialize queues and threads<a name="line.75"></a>
+<span class="sourceLineNo">076</span>    for (String node : nodes) {<a name="line.76"></a>
+<span class="sourceLineNo">077</span>      BlockingQueue&lt;byte[]&gt; queue = new ArrayBlockingQueue&lt;&gt;(1);<a name="line.77"></a>
+<span class="sourceLineNo">078</span>      queues.put(node, queue);<a name="line.78"></a>
+<span class="sourceLineNo">079</span>      Thread updater = new ClientZkUpdater(node, queue);<a name="line.79"></a>
+<span class="sourceLineNo">080</span>      updater.setDaemon(true);<a name="line.80"></a>
+<span class="sourceLineNo">081</span>      updater.start();<a name="line.81"></a>
+<span class="sourceLineNo">082</span>      watchAndCheckExists(node);<a name="line.82"></a>
+<span class="sourceLineNo">083</span>    }<a name="line.83"></a>
+<span class="sourceLineNo">084</span>  }<a name="line.84"></a>
+<span class="sourceLineNo">085</span><a name="line.85"></a>
+<span class="sourceLineNo">086</span>  private void watchAndCheckExists(String node) {<a name="line.86"></a>
+<span class="sourceLineNo">087</span>    try {<a name="line.87"></a>
+<span class="sourceLineNo">088</span>      if (ZKUtil.watchAndCheckExists(watcher, node)) {<a name="line.88"></a>
+<span class="sourceLineNo">089</span>        byte[] data = ZKUtil.getDataAndWatch(watcher, node);<a name="line.89"></a>
+<span class="sourceLineNo">090</span>        if (data != null) {<a name="line.90"></a>
+<span class="sourceLineNo">091</span>          // put the data into queue<a name="line.91"></a>
+<span class="sourceLineNo">092</span>          upsertQueue(node, data);<a name="line.92"></a>
+<span class="sourceLineNo">093</span>        } else {<a name="line.93"></a>
+<span class="sourceLineNo">094</span>          // It existed but now does not, should has been tracked by our watcher, ignore<a name="line.94"></a>
+<span class="sourceLineNo">095</span>          LOG.debug("Found no data from " + node);<a name="line.95"></a>
+<span class="sourceLineNo">096</span>          watchAndCheckExists(node);<a name="line.96"></a>
+<span class="sourceLineNo">097</span>        }<a name="line.97"></a>
+<span class="sourceLineNo">098</span>      } else {<a name="line.98"></a>
+<span class="sourceLineNo">099</span>        // cleanup stale ZNodes on client ZK to avoid invalid requests to server<a name="line.99"></a>
+<span class="sourceLineNo">100</span>        ZKUtil.deleteNodeFailSilent(clientZkWatcher, node);<a name="line.100"></a>
+<span class="sourceLineNo">101</span>      }<a name="line.101"></a>
+<span class="sourceLineNo">102</span>    } catch (KeeperException e) {<a name="line.102"></a>
+<span class="sourceLineNo">103</span>      server.abort("Unexpected exception during initialization, aborting", e);<a name="line.103"></a>
+<span class="sourceLineNo">104</span>    }<a name="line.104"></a>
+<span class="sourceLineNo">105</span>  }<a name="line.105"></a>
+<span class="sourceLineNo">106</span><a name="line.106"></a>
+<span class="sourceLineNo">107</span>  /**<a name="line.107"></a>
+<span class="sourceLineNo">108</span>   * Update the value of the single element in queue if any, or else insert.<a name="line.108"></a>
+<span class="sourceLineNo">109</span>   * &lt;p/&gt;<a name="line.109"></a>
+<span class="sourceLineNo">110</span>   * We only need to synchronize the latest znode value to client ZK rather than synchronize each<a name="line.110"></a>
+<span class="sourceLineNo">111</span>   * time<a name="line.111"></a>
+<span class="sourceLineNo">112</span>   * @param data the data to write to queue<a name="line.112"></a>
+<span class="sourceLineNo">113</span>   */<a name="line.113"></a>
+<span class="sourceLineNo">114</span>  private void upsertQueue(String node, byte[] data) {<a name="line.114"></a>
+<span class="sourceLineNo">115</span>    BlockingQueue&lt;byte[]&gt; queue = queues.get(node);<a name="line.115"></a>
+<span class="sourceLineNo">116</span>    synchronized (queue) {<a name="line.116"></a>
+<span class="sourceLineNo">117</span>      queue.poll();<a name="line.117"></a>
+<span class="sourceLineNo">118</span>      queue.offer(data);<a name="line.118"></a>
+<span class="sourceLineNo">119</span>    }<a name="line.119"></a>
+<span class="sourceLineNo">120</span>  }<a name="line.120"></a>
+<span class="sourceLineNo">121</span><a name="line.121"></a>
+<span class="sourceLineNo">122</span>  /**<a name="line.122"></a>
+<span class="sourceLineNo">123</span>   * Set data for client ZK and retry until succeed. Be very careful to prevent dead loop when<a name="line.123"></a>
+<span class="sourceLineNo">124</span>   * modifying this method<a name="line.124"></a>
+<span class="sourceLineNo">125</span>   * @param node the znode to set on client ZK<a name="line.125"></a>
+<span class="sourceLineNo">126</span>   * @param data the data to set to client ZK<a name="line.126"></a>
+<span class="sourceLineNo">127</span>   * @throws InterruptedException if the thread is interrupted during process<a name="line.127"></a>
+<span class="sourceLineNo">128</span>   */<a name="line.128"></a>
+<span class="sourceLineNo">129</span>  private final void setDataForClientZkUntilSuccess(String node, byte[] data)<a name="line.129"></a>
+<span class="sourceLineNo">130</span>      throws InterruptedException {<a name="line.130"></a>
+<span class="sourceLineNo">131</span>    while (!server.isStopped()) {<a name="line.131"></a>
+<span class="sourceLineNo">132</span>      try {<a name="line.132"></a>
+<span class="sourceLineNo">133</span>        LOG.debug("Set data for remote " + node + ", client zk wather: " + clientZkWatcher);<a name="line.133"></a>
+<span class="sourceLineNo">134</span>        ZKUtil.setData(clientZkWatcher, node, data);<a name="line.134"></a>
+<span class="sourceLineNo">135</span>        break;<a name="line.135"></a>
+<span class="sourceLineNo">136</span>      } catch (KeeperException.NoNodeException nne) {<a name="line.136"></a>
+<span class="sourceLineNo">137</span>        // Node doesn't exist, create it and set value<a name="line.137"></a>
+<span class="sourceLineNo">138</span>        try {<a name="line.138"></a>
+<span class="sourceLineNo">139</span>          ZKUtil.createNodeIfNotExistsNoWatch(clientZkWatcher, node, data, CreateMode.PERSISTENT);<a name="line.139"></a>
+<span class="sourceLineNo">140</span>          break;<a name="line.140"></a>
+<span class="sourceLineNo">141</span>        } catch (KeeperException.ConnectionLossException<a name="line.141"></a>
+<span class="sourceLineNo">142</span>            | KeeperException.SessionExpiredException ee) {<a name="line.142"></a>
+<span class="sourceLineNo">143</span>          reconnectAfterExpiration();<a name="line.143"></a>
+<span class="sourceLineNo">144</span>        } catch (KeeperException e) {<a name="line.144"></a>
+<span class="sourceLineNo">145</span>          LOG.warn(<a name="line.145"></a>
+<span class="sourceLineNo">146</span>            "Failed to create znode " + node + " due to: " + e.getMessage() + ", will retry later");<a name="line.146"></a>
+<span class="sourceLineNo">147</span>        }<a name="line.147"></a>
+<span class="sourceLineNo">148</span>      } catch (KeeperException.ConnectionLossException<a name="line.148"></a>
+<span class="sourceLineNo">149</span>          | KeeperException.SessionExpiredException ee) {<a name="line.149"></a>
+<span class="sourceLineNo">150</span>        reconnectAfterExpiration();<a name="line.150"></a>
+<span class="sourceLineNo">151</span>      } catch (KeeperException e) {<a name="line.151"></a>
+<span class="sourceLineNo">152</span>        LOG.debug("Failed to set data to client ZK, will retry later", e);<a name="line.152"></a>
+<span class="sourceLineNo">153</span>      }<a name="line.153"></a>
+<span class="sourceLineNo">154</span>      Threads.sleep(HConstants.SOCKET_RETRY_WAIT_MS);<a name="line.154"></a>
+<span class="sourceLineNo">155</span>    }<a name="line.155"></a>
+<span class="sourceLineNo">156</span>  }<a name="line.156"></a>
+<span class="sourceLineNo">157</span><a name="line.157"></a>
+<span class="sourceLineNo">158</span>  private final void reconnectAfterExpiration() throws InterruptedException {<a name="line.158"></a>
+<span class="sourceLineNo">159</span>    LOG.warn("ZK session expired or lost. Retry a new connection...");<a name="line.159"></a>
+<span class="sourceLineNo">160</span>    try {<a name="line.160"></a>
+<span class="sourceLineNo">161</span>      clientZkWatcher.reconnectAfterExpiration();<a name="line.161"></a>
+<span class="sourceLineNo">162</span>    } catch (IOException | KeeperException e) {<a name="line.162"></a>
+<span class="sourceLineNo">163</span>      LOG.warn("Failed to reconnect to client zk after session expiration, will retry later", e);<a name="line.163"></a>
+<span class="sourceLineNo">164</span>    }<a name="line.164"></a>
+<span class="sourceLineNo">165</span>  }<a name="line.165"></a>
+<span class="sourceLineNo">166</span><a name="line.166"></a>
+<span class="sourceLineNo">167</span>  @Override<a name="line.167"></a>
+<span class="sourceLineNo">168</span>  public void nodeCreated(String path) {<a name="line.168"></a>
+<span class="sourceLineNo">169</span>    if (!validate(path)) {<a name="line.169"></a>
+<span class="sourceLineNo">170</span>      return;<a name="line.170"></a>
+<span class="sourceLineNo">171</span>    }<a name="line.171"></a>
+<span class="sourceLineNo">172</span>    try {<a name="line.172"></a>
+<span class="sourceLineNo">173</span>      byte[] data = ZKUtil.getDataAndWatch(watcher, path);<a name="line.173"></a>
+<span class="sourceLineNo">174</span>      upsertQueue(path, data);<a name="line.174"></a>
+<span class="sourceLineNo">175</span>    } catch (KeeperException e) {<a name="line.175"></a>
+<span class="sourceLineNo">176</span>      LOG.warn("Unexpected exception handling nodeCreated event", e);<a name="line.176"></a>
+<span class="sourceLineNo">177</span>    }<a name="line.177"></a>
+<span class="sourceLineNo">178</span>  }<a name="line.178"></a>
+<span class="sourceLineNo">179</span><a name="line.179"></a>
+<span class="sourceLineNo">180</span>  @Override<a name="line.180"></a>
+<span class="sourceLineNo">181</span>  public void nodeDataChanged(String path) {<a name="line.181"></a>
+<span class="sourceLineNo">182</span>    if (validate(path)) {<a name="line.182"></a>
+<span class="sourceLineNo">183</span>      nodeCreated(path);<a name="line.183"></a>
+<span class="sourceLineNo">184</span>    }<a name="line.184"></a>
+<span class="sourceLineNo">185</span>  }<a name="line.185"></a>
+<span class="sourceLineNo">186</span><a name="line.186"></a>
+<span class="sourceLineNo">187</span>  @Override<a name="line.187"></a>
+<span class="sourceLineNo">188</span>  public synchronized void nodeDeleted(String path) {<a name="line.188"></a>
+<span class="sourceLineNo">189</span>    if (validate(path)) {<a name="line.189"></a>
+<span class="sourceLineNo">190</span>      try {<a name="line.190"></a>
+<span class="sourceLineNo">191</span>        if (ZKUtil.watchAndCheckExists(watcher, path)) {<a name="line.191"></a>
+<span class="sourceLineNo">192</span>          nodeCreated(path);<a name="line.192"></a>
+<span class="sourceLineNo">193</span>        }<a name="line.193"></a>
+<span class="sourceLineNo">194</span>      } catch (KeeperException e) {<a name="line.194"></a>
+<span class="sourceLineNo">195</span>        LOG.warn("Unexpected exception handling nodeDeleted event for path: " + path, e);<a name="line.195"></a>
+<span class="sourceLineNo">196</span>      }<a name="line.196"></a>
+<span class="sourceLineNo">197</span>    }<a name="line.197"></a>
+<span class="sourceLineNo">198</span>  }<a name="line.198"></a>
+<span class="sourceLineNo">199</span><a name="line.199"></a>
+<span class="sourceLineNo">200</span>  /**<a name="line.200"></a>
+<span class="sourceLineNo">201</span>   * Validate whether a znode path is watched by us<a name="line.201"></a>
+<span class="sourceLineNo">202</span>   * @param path the path to validate<a name="line.202"></a>
+<span class="sourceLineNo">203</span>   * @return true if the znode is watched by us<a name="line.203"></a>
+<span class="sourceLineNo">204</span>   */<a name="line.204"></a>
+<span class="sourceLineNo">205</span>  abstract boolean validate(String path);<a name="line.205"></a>
+<span class="sourceLineNo">206</span><a name="line.206"></a>
+<span class="sourceLineNo">207</span>  /**<a name="line.207"></a>
+<span class="sourceLineNo">208</span>   * @return the znode(s) to watch<a name="line.208"></a>
+<span class="sourceLineNo">209</span>   */<a name="line.209"></a>
+<span class="sourceLineNo">210</span>  abstract Collection&lt;String&gt; getNodesToWatch();<a name="line.210"></a>
+<span class="sourceLineNo">211</span><a name="line.211"></a>
+<span class="sourceLineNo">212</span>  /**<a name="line.212"></a>
+<span class="sourceLineNo">213</span>   * Thread to synchronize znode data to client ZK cluster<a name="line.213"></a>
+<span class="sourceLineNo">214</span>   */<a name="line.214"></a>
+<span class="sourceLineNo">215</span>  class ClientZkUpdater extends Thread {<a name="line.215"></a>
+<span class="sourceLineNo">216</span>    final String znode;<a name="line.216"></a>
+<span class="sourceLineNo">217</span>    final BlockingQueue&lt;byte[]&gt; queue;<a name="line.217"></a>
+<span class="sourceLineNo">218</span><a name="line.218"></a>
+<span class="sourceLineNo">219</span>    public ClientZkUpdater(String znode, BlockingQueue&lt;byte[]&gt; queue) {<a name="line.219"></a>
+<span class="sourceLineNo">220</span>      this.znode = znode;<a name="line.220"></a>
+<span class="sourceLineNo">221</span>      this.queue = queue;<a name="line.221"></a>
+<span class="sourceLineNo">222</span>      setName("ClientZKUpdater-" + znode);<a name="line.222"></a>
+<span class="sourceLineNo">223</span>    }<a name="line.223"></a>
+<span class="sourceLineNo">224</span><a name="line.224"></a>
+<span class="sourceLineNo">225</span>    @Override<a name="line.225"></a>
+<span class="sourceLineNo">226</span>    public void run() {<a name="line.226"></a>
+<span class="sourceLineNo">227</span>      while (!server.isStopped()) {<a name="line.227"></a>
+<span class="sourceLineNo">228</span>        try {<a name="line.228"></a>
+<span class="sourceLineNo">229</span>          byte[] data = queue.take();<a name="line.229"></a>
+<span class="sourceLineNo">230</span>          setDataForClientZkUntilSuccess(znode, data);<a name="line.230"></a>
+<span class="sourceLineNo">231</span>        } catch (InterruptedException e) {<a name="line.231"></a>
+<span class="sourceLineNo">232</span>          if (LOG.isDebugEnabled()) {<a name="line.232"></a>
+<span class="sourceLineNo">233</span>            LOG.debug(<a name="line.233"></a>
+<span class="sourceLineNo">234</span>              "Interrupted while checking whether need to update meta location to client zk");<a name="line.234"></a>
+<span class="sourceLineNo">235</span>          }<a name="line.235"></a>
+<span class="sourceLineNo">236</span>          Thread.currentThread().interrupt();<a name="line.236"></a>
+<span class="sourceLineNo">237</span>          break;<a name="line.237"></a>
+<span class="sourceLineNo">238</span>        }<a name="line.238"></a>
+<span class="sourceLineNo">239</span>      }<a name="line.239"></a>
+<span class="sourceLineNo">240</span>    }<a name="line.240"></a>
+<span class="sourceLineNo">241</span>  }<a name="line.241"></a>
+<span class="sourceLineNo">242</span>}<a name="line.242"></a>
 
 
 

http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1facf1d3/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.html b/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.html
index 3e25d25..87545d3 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/master/zksyncer/ClientZKSyncer.html
@@ -33,220 +33,221 @@
 <span class="sourceLineNo">025</span>import java.util.concurrent.ArrayBlockingQueue;<a name="line.25"></a>
 <span class="sourceLineNo">026</span>import java.util.concurrent.BlockingQueue;<a name="line.26"></a>
 <span class="sourceLineNo">027</span><a name="line.27"></a>
-<span class="sourceLineNo">028</span>import org.apache.commons.logging.Log;<a name="line.28"></a>
-<span class="sourceLineNo">029</span>import org.apache.commons.logging.LogFactory;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.HConstants;<a name="line.30"></a>
-<span class="sourceLineNo">031</span>import org.apache.hadoop.hbase.Server;<a name="line.31"></a>
-<span class="sourceLineNo">032</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.32"></a>
-<span class="sourceLineNo">033</span>import org.apache.hadoop.hbase.zookeeper.ZKListener;<a name="line.33"></a>
-<span class="sourceLineNo">034</span>import org.apache.hadoop.hbase.zookeeper.ZKUtil;<a name="line.34"></a>
-<span class="sourceLineNo">035</span>import org.apache.hadoop.hbase.zookeeper.ZKWatcher;<a name="line.35"></a>
-<span class="sourceLineNo">036</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.36"></a>
-<span class="sourceLineNo">037</span>import org.apache.zookeeper.CreateMode;<a name="line.37"></a>
-<span class="sourceLineNo">038</span>import org.apache.zookeeper.KeeperException;<a name="line.38"></a>
-<span class="sourceLineNo">039</span><a name="line.39"></a>
-<span class="sourceLineNo">040</span>/**<a name="line.40"></a>
-<span class="sourceLineNo">041</span> * Tracks the target znode(s) on server ZK cluster and synchronize them to client ZK cluster if<a name="line.41"></a>
-<span class="sourceLineNo">042</span> * changed<a name="line.42"></a>
-<span class="sourceLineNo">043</span> * &lt;p/&gt;<a name="line.43"></a>
-<span class="sourceLineNo">044</span> * The target znode(s) is given through {@link #getNodesToWatch()} method<a name="line.44"></a>
-<span class="sourceLineNo">045</span> */<a name="line.45"></a>
-<span class="sourceLineNo">046</span>@InterfaceAudience.Private<a name="line.46"></a>
-<span class="sourceLineNo">047</span>public abstract class ClientZKSyncer extends ZKListener {<a name="line.47"></a>
-<span class="sourceLineNo">048</span>  private static final Log LOG = LogFactory.getLog(ClientZKSyncer.class);<a name="line.48"></a>
-<span class="sourceLineNo">049</span>  private final Server server;<a name="line.49"></a>
-<span class="sourceLineNo">050</span>  private final ZKWatcher clientZkWatcher;<a name="line.50"></a>
-<span class="sourceLineNo">051</span>  // We use queues and daemon threads to synchronize the data to client ZK cluster<a name="line.51"></a>
-<span class="sourceLineNo">052</span>  // to avoid blocking the single event thread for watchers<a name="line.52"></a>
-<span class="sourceLineNo">053</span>  private final Map&lt;String, BlockingQueue&lt;byte[]&gt;&gt; queues;<a name="line.53"></a>
-<span class="sourceLineNo">054</span><a name="line.54"></a>
-<span class="sourceLineNo">055</span>  public ClientZKSyncer(ZKWatcher watcher, ZKWatcher clientZkWatcher, Server server) {<a name="line.55"></a>
-<span class="sourceLineNo">056</span>    super(watcher);<a name="line.56"></a>
-<span class="sourceLineNo">057</span>    this.server = server;<a name="line.57"></a>
-<span class="sourceLineNo">058</span>    this.clientZkWatcher = clientZkWatcher;<a name="line.58"></a>
-<span class="sourceLineNo">059</span>    this.queues = new HashMap&lt;&gt;();<a name="line.59"></a>
-<span class="sourceLineNo">060</span>  }<a name="line.60"></a>
-<span class="sourceLineNo">061</span><a name="line.61"></a>
-<span class="sourceLineNo">062</span>  /**<a name="line.62"></a>
-<span class="sourceLineNo">063</span>   * Starts the syncer<a name="line.63"></a>
-<span class="sourceLineNo">064</span>   * @throws KeeperException if error occurs when trying to create base nodes on client ZK<a name="line.64"></a>
-<span class="sourceLineNo">065</span>   */<a name="line.65"></a>
-<span class="sourceLineNo">066</span>  public void start() throws KeeperException {<a name="line.66"></a>
-<span class="sourceLineNo">067</span>    LOG.debug("Starting " + getClass().getSimpleName());<a name="line.67"></a>
-<span class="sourceLineNo">068</span>    this.watcher.registerListener(this);<a name="line.68"></a>
-<span class="sourceLineNo">069</span>    // create base znode on remote ZK<a name="line.69"></a>
-<span class="sourceLineNo">070</span>    ZKUtil.createWithParents(clientZkWatcher, watcher.znodePaths.baseZNode);<a name="line.70"></a>
-<span class="sourceLineNo">071</span>    // set meta znodes for client ZK<a name="line.71"></a>
-<span class="sourceLineNo">072</span>    Collection&lt;String&gt; nodes = getNodesToWatch();<a name="line.72"></a>
-<span class="sourceLineNo">073</span>    LOG.debug("Znodes to watch: " + nodes);<a name="line.73"></a>
-<span class="sourceLineNo">074</span>    // initialize queues and threads<a name="line.74"></a>
-<span class="sourceLineNo">075</span>    for (String node : nodes) {<a name="line.75"></a>
-<span class="sourceLineNo">076</span>      BlockingQueue&lt;byte[]&gt; queue = new ArrayBlockingQueue&lt;&gt;(1);<a name="line.76"></a>
-<span class="sourceLineNo">077</span>      queues.put(node, queue);<a name="line.77"></a>
-<span class="sourceLineNo">078</span>      Thread updater = new ClientZkUpdater(node, queue);<a name="line.78"></a>
-<span class="sourceLineNo">079</span>      updater.setDaemon(true);<a name="line.79"></a>
-<span class="sourceLineNo">080</span>      updater.start();<a name="line.80"></a>
-<span class="sourceLineNo">081</span>      watchAndCheckExists(node);<a name="line.81"></a>
-<span class="sourceLineNo">082</span>    }<a name="line.82"></a>
-<span class="sourceLineNo">083</span>  }<a name="line.83"></a>
-<span class="sourceLineNo">084</span><a name="line.84"></a>
-<span class="sourceLineNo">085</span>  private void watchAndCheckExists(String node) {<a name="line.85"></a>
-<span class="sourceLineNo">086</span>    try {<a name="line.86"></a>
-<span class="sourceLineNo">087</span>      if (ZKUtil.watchAndCheckExists(watcher, node)) {<a name="line.87"></a>
-<span class="sourceLineNo">088</span>        byte[] data = ZKUtil.getDataAndWatch(watcher, node);<a name="line.88"></a>
-<span class="sourceLineNo">089</span>        if (data != null) {<a name="line.89"></a>
-<span class="sourceLineNo">090</span>          // put the data into queue<a name="line.90"></a>
-<span class="sourceLineNo">091</span>          upsertQueue(node, data);<a name="line.91"></a>
-<span class="sourceLineNo">092</span>        } else {<a name="line.92"></a>
-<span class="sourceLineNo">093</span>          // It existed but now does not, should has been tracked by our watcher, ignore<a name="line.93"></a>
-<span class="sourceLineNo">094</span>          LOG.debug("Found no data from " + node);<a name="line.94"></a>
-<span class="sourceLineNo">095</span>          watchAndCheckExists(node);<a name="line.95"></a>
-<span class="sourceLineNo">096</span>        }<a name="line.96"></a>
-<span class="sourceLineNo">097</span>      } else {<a name="line.97"></a>
-<span class="sourceLineNo">098</span>        // cleanup stale ZNodes on client ZK to avoid invalid requests to server<a name="line.98"></a>
-<span class="sourceLineNo">099</span>        ZKUtil.deleteNodeFailSilent(clientZkWatcher, node);<a name="line.99"></a>
-<span class="sourceLineNo">100</span>      }<a name="line.100"></a>
-<span class="sourceLineNo">101</span>    } catch (KeeperException e) {<a name="line.101"></a>
-<span class="sourceLineNo">102</span>      server.abort("Unexpected exception during initialization, aborting", e);<a name="line.102"></a>
-<span class="sourceLineNo">103</span>    }<a name="line.103"></a>
-<span class="sourceLineNo">104</span>  }<a name="line.104"></a>
-<span class="sourceLineNo">105</span><a name="line.105"></a>
-<span class="sourceLineNo">106</span>  /**<a name="line.106"></a>
-<span class="sourceLineNo">107</span>   * Update the value of the single element in queue if any, or else insert.<a name="line.107"></a>
-<span class="sourceLineNo">108</span>   * &lt;p/&gt;<a name="line.108"></a>
-<span class="sourceLineNo">109</span>   * We only need to synchronize the latest znode value to client ZK rather than synchronize each<a name="line.109"></a>
-<span class="sourceLineNo">110</span>   * time<a name="line.110"></a>
-<span class="sourceLineNo">111</span>   * @param data the data to write to queue<a name="line.111"></a>
-<span class="sourceLineNo">112</span>   */<a name="line.112"></a>
-<span class="sourceLineNo">113</span>  private void upsertQueue(String node, byte[] data) {<a name="line.113"></a>
-<span class="sourceLineNo">114</span>    BlockingQueue&lt;byte[]&gt; queue = queues.get(node);<a name="line.114"></a>
-<span class="sourceLineNo">115</span>    synchronized (queue) {<a name="line.115"></a>
-<span class="sourceLineNo">116</span>      queue.poll();<a name="line.116"></a>
-<span class="sourceLineNo">117</span>      queue.offer(data);<a name="line.117"></a>
-<span class="sourceLineNo">118</span>    }<a name="line.118"></a>
-<span class="sourceLineNo">119</span>  }<a name="line.119"></a>
-<span class="sourceLineNo">120</span><a name="line.120"></a>
-<span class="sourceLineNo">121</span>  /**<a name="line.121"></a>
-<span class="sourceLineNo">122</span>   * Set data for client ZK and retry until succeed. Be very careful to prevent dead loop when<a name="line.122"></a>
-<span class="sourceLineNo">123</span>   * modifying this method<a name="line.123"></a>
-<span class="sourceLineNo">124</span>   * @param node the znode to set on client ZK<a name="line.124"></a>
-<span class="sourceLineNo">125</span>   * @param data the data to set to client ZK<a name="line.125"></a>
-<span class="sourceLineNo">126</span>   * @throws InterruptedException if the thread is interrupted during process<a name="line.126"></a>
-<span class="sourceLineNo">127</span>   */<a name="line.127"></a>
-<span class="sourceLineNo">128</span>  private final void setDataForClientZkUntilSuccess(String node, byte[] data)<a name="line.128"></a>
-<span class="sourceLineNo">129</span>      throws InterruptedException {<a name="line.129"></a>
-<span class="sourceLineNo">130</span>    while (!server.isStopped()) {<a name="line.130"></a>
-<span class="sourceLineNo">131</span>      try {<a name="line.131"></a>
-<span class="sourceLineNo">132</span>        LOG.debug("Set data for remote " + node + ", client zk wather: " + clientZkWatcher);<a name="line.132"></a>
-<span class="sourceLineNo">133</span>        ZKUtil.setData(clientZkWatcher, node, data);<a name="line.133"></a>
-<span class="sourceLineNo">134</span>        break;<a name="line.134"></a>
-<span class="sourceLineNo">135</span>      } catch (KeeperException.NoNodeException nne) {<a name="line.135"></a>
-<span class="sourceLineNo">136</span>        // Node doesn't exist, create it and set value<a name="line.136"></a>
-<span class="sourceLineNo">137</span>        try {<a name="line.137"></a>
-<span class="sourceLineNo">138</span>          ZKUtil.createNodeIfNotExistsNoWatch(clientZkWatcher, node, data, CreateMode.PERSISTENT);<a name="line.138"></a>
-<span class="sourceLineNo">139</span>          break;<a name="line.139"></a>
-<span class="sourceLineNo">140</span>        } catch (KeeperException.ConnectionLossException<a name="line.140"></a>
-<span class="sourceLineNo">141</span>            | KeeperException.SessionExpiredException ee) {<a name="line.141"></a>
-<span class="sourceLineNo">142</span>          reconnectAfterExpiration();<a name="line.142"></a>
-<span class="sourceLineNo">143</span>        } catch (KeeperException e) {<a name="line.143"></a>
-<span class="sourceLineNo">144</span>          LOG.warn(<a name="line.144"></a>
-<span class="sourceLineNo">145</span>            "Failed to create znode " + node + " due to: " + e.getMessage() + ", will retry later");<a name="line.145"></a>
-<span class="sourceLineNo">146</span>        }<a name="line.146"></a>
-<span class="sourceLineNo">147</span>      } catch (KeeperException.ConnectionLossException<a name="line.147"></a>
-<span class="sourceLineNo">148</span>          | KeeperException.SessionExpiredException ee) {<a name="line.148"></a>
-<span class="sourceLineNo">149</span>        reconnectAfterExpiration();<a name="line.149"></a>
-<span class="sourceLineNo">150</span>      } catch (KeeperException e) {<a name="line.150"></a>
-<span class="sourceLineNo">151</span>        LOG.debug("Failed to set data to client ZK, will retry later", e);<a name="line.151"></a>
-<span class="sourceLineNo">152</span>      }<a name="line.152"></a>
-<span class="sourceLineNo">153</span>      Threads.sleep(HConstants.SOCKET_RETRY_WAIT_MS);<a name="line.153"></a>
-<span class="sourceLineNo">154</span>    }<a name="line.154"></a>
-<span class="sourceLineNo">155</span>  }<a name="line.155"></a>
-<span class="sourceLineNo">156</span><a name="line.156"></a>
-<span class="sourceLineNo">157</span>  private final void reconnectAfterExpiration() throws InterruptedException {<a name="line.157"></a>
-<span class="sourceLineNo">158</span>    LOG.warn("ZK session expired or lost. Retry a new connection...");<a name="line.158"></a>
-<span class="sourceLineNo">159</span>    try {<a name="line.159"></a>
-<span class="sourceLineNo">160</span>      clientZkWatcher.reconnectAfterExpiration();<a name="line.160"></a>
-<span class="sourceLineNo">161</span>    } catch (IOException | KeeperException e) {<a name="line.161"></a>
-<span class="sourceLineNo">162</span>      LOG.warn("Failed to reconnect to client zk after session expiration, will retry later", e);<a name="line.162"></a>
-<span class="sourceLineNo">163</span>    }<a name="line.163"></a>
-<span class="sourceLineNo">164</span>  }<a name="line.164"></a>
-<span class="sourceLineNo">165</span><a name="line.165"></a>
-<span class="sourceLineNo">166</span>  @Override<a name="line.166"></a>
-<span class="sourceLineNo">167</span>  public void nodeCreated(String path) {<a name="line.167"></a>
-<span class="sourceLineNo">168</span>    if (!validate(path)) {<a name="line.168"></a>
-<span class="sourceLineNo">169</span>      return;<a name="line.169"></a>
-<span class="sourceLineNo">170</span>    }<a name="line.170"></a>
-<span class="sourceLineNo">171</span>    try {<a name="line.171"></a>
-<span class="sourceLineNo">172</span>      byte[] data = ZKUtil.getDataAndWatch(watcher, path);<a name="line.172"></a>
-<span class="sourceLineNo">173</span>      upsertQueue(path, data);<a name="line.173"></a>
-<span class="sourceLineNo">174</span>    } catch (KeeperException e) {<a name="line.174"></a>
-<span class="sourceLineNo">175</span>      LOG.warn("Unexpected exception handling nodeCreated event", e);<a name="line.175"></a>
-<span class="sourceLineNo">176</span>    }<a name="line.176"></a>
-<span class="sourceLineNo">177</span>  }<a name="line.177"></a>
-<span class="sourceLineNo">178</span><a name="line.178"></a>
-<span class="sourceLineNo">179</span>  @Override<a name="line.179"></a>
-<span class="sourceLineNo">180</span>  public void nodeDataChanged(String path) {<a name="line.180"></a>
-<span class="sourceLineNo">181</span>    if (validate(path)) {<a name="line.181"></a>
-<span class="sourceLineNo">182</span>      nodeCreated(path);<a name="line.182"></a>
-<span class="sourceLineNo">183</span>    }<a name="line.183"></a>
-<span class="sourceLineNo">184</span>  }<a name="line.184"></a>
-<span class="sourceLineNo">185</span><a name="line.185"></a>
-<span class="sourceLineNo">186</span>  @Override<a name="line.186"></a>
-<span class="sourceLineNo">187</span>  public synchronized void nodeDeleted(String path) {<a name="line.187"></a>
-<span class="sourceLineNo">188</span>    if (validate(path)) {<a name="line.188"></a>
-<span class="sourceLineNo">189</span>      try {<a name="line.189"></a>
-<span class="sourceLineNo">190</span>        if (ZKUtil.watchAndCheckExists(watcher, path)) {<a name="line.190"></a>
-<span class="sourceLineNo">191</span>          nodeCreated(path);<a name="line.191"></a>
-<span class="sourceLineNo">192</span>        }<a name="line.192"></a>
-<span class="sourceLineNo">193</span>      } catch (KeeperException e) {<a name="line.193"></a>
-<span class="sourceLineNo">194</span>        LOG.warn("Unexpected exception handling nodeDeleted event for path: " + path, e);<a name="line.194"></a>
-<span class="sourceLineNo">195</span>      }<a name="line.195"></a>
-<span class="sourceLineNo">196</span>    }<a name="line.196"></a>
-<span class="sourceLineNo">197</span>  }<a name="line.197"></a>
-<span class="sourceLineNo">198</span><a name="line.198"></a>
-<span class="sourceLineNo">199</span>  /**<a name="line.199"></a>
-<span class="sourceLineNo">200</span>   * Validate whether a znode path is watched by us<a name="line.200"></a>
-<span class="sourceLineNo">201</span>   * @param path the path to validate<a name="line.201"></a>
-<span class="sourceLineNo">202</span>   * @return true if the znode is watched by us<a name="line.202"></a>
-<span class="sourceLineNo">203</span>   */<a name="line.203"></a>
-<span class="sourceLineNo">204</span>  abstract boolean validate(String path);<a name="line.204"></a>
-<span class="sourceLineNo">205</span><a name="line.205"></a>
-<span class="sourceLineNo">206</span>  /**<a name="line.206"></a>
-<span class="sourceLineNo">207</span>   * @return the znode(s) to watch<a name="line.207"></a>
-<span class="sourceLineNo">208</span>   */<a name="line.208"></a>
-<span class="sourceLineNo">209</span>  abstract Collection&lt;String&gt; getNodesToWatch();<a name="line.209"></a>
-<span class="sourceLineNo">210</span><a name="line.210"></a>
-<span class="sourceLineNo">211</span>  /**<a name="line.211"></a>
-<span class="sourceLineNo">212</span>   * Thread to synchronize znode data to client ZK cluster<a name="line.212"></a>
-<span class="sourceLineNo">213</span>   */<a name="line.213"></a>
-<span class="sourceLineNo">214</span>  class ClientZkUpdater extends Thread {<a name="line.214"></a>
-<span class="sourceLineNo">215</span>    final String znode;<a name="line.215"></a>
-<span class="sourceLineNo">216</span>    final BlockingQueue&lt;byte[]&gt; queue;<a name="line.216"></a>
-<span class="sourceLineNo">217</span><a name="line.217"></a>
-<span class="sourceLineNo">218</span>    public ClientZkUpdater(String znode, BlockingQueue&lt;byte[]&gt; queue) {<a name="line.218"></a>
-<span class="sourceLineNo">219</span>      this.znode = znode;<a name="line.219"></a>
-<span class="sourceLineNo">220</span>      this.queue = queue;<a name="line.220"></a>
-<span class="sourceLineNo">221</span>      setName("ClientZKUpdater-" + znode);<a name="line.221"></a>
-<span class="sourceLineNo">222</span>    }<a name="line.222"></a>
-<span class="sourceLineNo">223</span><a name="line.223"></a>
-<span class="sourceLineNo">224</span>    @Override<a name="line.224"></a>
-<span class="sourceLineNo">225</span>    public void run() {<a name="line.225"></a>
-<span class="sourceLineNo">226</span>      while (!server.isStopped()) {<a name="line.226"></a>
-<span class="sourceLineNo">227</span>        try {<a name="line.227"></a>
-<span class="sourceLineNo">228</span>          byte[] data = queue.take();<a name="line.228"></a>
-<span class="sourceLineNo">229</span>          setDataForClientZkUntilSuccess(znode, data);<a name="line.229"></a>
-<span class="sourceLineNo">230</span>        } catch (InterruptedException e) {<a name="line.230"></a>
-<span class="sourceLineNo">231</span>          if (LOG.isDebugEnabled()) {<a name="line.231"></a>
-<span class="sourceLineNo">232</span>            LOG.debug(<a name="line.232"></a>
-<span class="sourceLineNo">233</span>              "Interrupted while checking whether need to update meta location to client zk");<a name="line.233"></a>
-<span class="sourceLineNo">234</span>          }<a name="line.234"></a>
-<span class="sourceLineNo">235</span>          Thread.currentThread().interrupt();<a name="line.235"></a>
-<span class="sourceLineNo">236</span>          break;<a name="line.236"></a>
-<span class="sourceLineNo">237</span>        }<a name="line.237"></a>
-<span class="sourceLineNo">238</span>      }<a name="line.238"></a>
-<span class="sourceLineNo">239</span>    }<a name="line.239"></a>
-<span class="sourceLineNo">240</span>  }<a name="line.240"></a>
-<span class="sourceLineNo">241</span>}<a name="line.241"></a>
+<span class="sourceLineNo">028</span>import org.apache.hadoop.hbase.HConstants;<a name="line.28"></a>
+<span class="sourceLineNo">029</span>import org.apache.hadoop.hbase.Server;<a name="line.29"></a>
+<span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.30"></a>
+<span class="sourceLineNo">031</span>import org.apache.hadoop.hbase.zookeeper.ZKListener;<a name="line.31"></a>
+<span class="sourceLineNo">032</span>import org.apache.hadoop.hbase.zookeeper.ZKUtil;<a name="line.32"></a>
+<span class="sourceLineNo">033</span>import org.apache.hadoop.hbase.zookeeper.ZKWatcher;<a name="line.33"></a>
+<span class="sourceLineNo">034</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.34"></a>
+<span class="sourceLineNo">035</span>import org.apache.zookeeper.CreateMode;<a name="line.35"></a>
+<span class="sourceLineNo">036</span>import org.apache.zookeeper.KeeperException;<a name="line.36"></a>
+<span class="sourceLineNo">037</span><a name="line.37"></a>
+<span class="sourceLineNo">038</span>import org.slf4j.Logger;<a name="line.38"></a>
+<span class="sourceLineNo">039</span>import org.slf4j.LoggerFactory;<a name="line.39"></a>
+<span class="sourceLineNo">040</span><a name="line.40"></a>
+<span class="sourceLineNo">041</span>/**<a name="line.41"></a>
+<span class="sourceLineNo">042</span> * Tracks the target znode(s) on server ZK cluster and synchronize them to client ZK cluster if<a name="line.42"></a>
+<span class="sourceLineNo">043</span> * changed<a name="line.43"></a>
+<span class="sourceLineNo">044</span> * &lt;p/&gt;<a name="line.44"></a>
+<span class="sourceLineNo">045</span> * The target znode(s) is given through {@link #getNodesToWatch()} method<a name="line.45"></a>
+<span class="sourceLineNo">046</span> */<a name="line.46"></a>
+<span class="sourceLineNo">047</span>@InterfaceAudience.Private<a name="line.47"></a>
+<span class="sourceLineNo">048</span>public abstract class ClientZKSyncer extends ZKListener {<a name="line.48"></a>
+<span class="sourceLineNo">049</span>  private static final Logger LOG = LoggerFactory.getLogger(ClientZKSyncer.class);<a name="line.49"></a>
+<span class="sourceLineNo">050</span>  private final Server server;<a name="line.50"></a>
+<span class="sourceLineNo">051</span>  private final ZKWatcher clientZkWatcher;<a name="line.51"></a>
+<span class="sourceLineNo">052</span>  // We use queues and daemon threads to synchronize the data to client ZK cluster<a name="line.52"></a>
+<span class="sourceLineNo">053</span>  // to avoid blocking the single event thread for watchers<a name="line.53"></a>
+<span class="sourceLineNo">054</span>  private final Map&lt;String, BlockingQueue&lt;byte[]&gt;&gt; queues;<a name="line.54"></a>
+<span class="sourceLineNo">055</span><a name="line.55"></a>
+<span class="sourceLineNo">056</span>  public ClientZKSyncer(ZKWatcher watcher, ZKWatcher clientZkWatcher, Server server) {<a name="line.56"></a>
+<span class="sourceLineNo">057</span>    super(watcher);<a name="line.57"></a>
+<span class="sourceLineNo">058</span>    this.server = server;<a name="line.58"></a>
+<span class="sourceLineNo">059</span>    this.clientZkWatcher = clientZkWatcher;<a name="line.59"></a>
+<span class="sourceLineNo">060</span>    this.queues = new HashMap&lt;&gt;();<a name="line.60"></a>
+<span class="sourceLineNo">061</span>  }<a name="line.61"></a>
+<span class="sourceLineNo">062</span><a name="line.62"></a>
+<span class="sourceLineNo">063</span>  /**<a name="line.63"></a>
+<span class="sourceLineNo">064</span>   * Starts the syncer<a name="line.64"></a>
+<span class="sourceLineNo">065</span>   * @throws KeeperException if error occurs when trying to create base nodes on client ZK<a name="line.65"></a>
+<span class="sourceLineNo">066</span>   */<a name="line.66"></a>
+<span class="sourceLineNo">067</span>  public void start() throws KeeperException {<a name="line.67"></a>
+<span class="sourceLineNo">068</span>    LOG.debug("Starting " + getClass().getSimpleName());<a name="line.68"></a>
+<span class="sourceLineNo">069</span>    this.watcher.registerListener(this);<a name="line.69"></a>
+<span class="sourceLineNo">070</span>    // create base znode on remote ZK<a name="line.70"></a>
+<span class="sourceLineNo">071</span>    ZKUtil.createWithParents(clientZkWatcher, watcher.znodePaths.baseZNode);<a name="line.71"></a>
+<span class="sourceLineNo">072</span>    // set meta znodes for client ZK<a name="line.72"></a>
+<span class="sourceLineNo">073</span>    Collection&lt;String&gt; nodes = getNodesToWatch();<a name="line.73"></a>
+<span class="sourceLineNo">074</span>    LOG.debug("Znodes to watch: " + nodes);<a name="line.74"></a>
+<span class="sourceLineNo">075</span>    // initialize queues and threads<a name="line.75"></a>
+<span class="sourceLineNo">076</span>    for (String node : nodes) {<a name="line.76"></a>
+<span class="sourceLineNo">077</span>      BlockingQueue&lt;byte[]&gt; queue = new ArrayBlockingQueue&lt;&gt;(1);<a name="line.77"></a>
+<span class="sourceLineNo">078</span>      queues.put(node, queue);<a name="line.78"></a>
+<span class="sourceLineNo">079</span>      Thread updater = new ClientZkUpdater(node, queue);<a name="line.79"></a>
+<span class="sourceLineNo">080</span>      updater.setDaemon(true);<a name="line.80"></a>
+<span class="sourceLineNo">081</span>      updater.start();<a name="line.81"></a>
+<span class="sourceLineNo">082</span>      watchAndCheckExists(node);<a name="line.82"></a>
+<span class="sourceLineNo">083</span>    }<a name="line.83"></a>
+<span class="sourceLineNo">084</span>  }<a name="line.84"></a>
+<span class="sourceLineNo">085</span><a name="line.85"></a>
+<span class="sourceLineNo">086</span>  private void watchAndCheckExists(String node) {<a name="line.86"></a>
+<span class="sourceLineNo">087</span>    try {<a name="line.87"></a>
+<span class="sourceLineNo">088</span>      if (ZKUtil.watchAndCheckExists(watcher, node)) {<a name="line.88"></a>
+<span class="sourceLineNo">089</span>        byte[] data = ZKUtil.getDataAndWatch(watcher, node);<a name="line.89"></a>
+<span class="sourceLineNo">090</span>        if (data != null) {<a name="line.90"></a>
+<span class="sourceLineNo">091</span>          // put the data into queue<a name="line.91"></a>
+<span class="sourceLineNo">092</span>          upsertQueue(node, data);<a name="line.92"></a>
+<span class="sourceLineNo">093</span>        } else {<a name="line.93"></a>
+<span class="sourceLineNo">094</span>          // It existed but now does not, should has been tracked by our watcher, ignore<a name="line.94"></a>
+<span class="sourceLineNo">095</span>          LOG.debug("Found no data from " + node);<a name="line.95"></a>
+<span class="sourceLineNo">096</span>          watchAndCheckExists(node);<a name="line.96"></a>
+<span class="sourceLineNo">097</span>        }<a name="line.97"></a>
+<span class="sourceLineNo">098</span>      } else {<a name="line.98"></a>
+<span class="sourceLineNo">099</span>        // cleanup stale ZNodes on client ZK to avoid invalid requests to server<a name="line.99"></a>
+<span class="sourceLineNo">100</span>        ZKUtil.deleteNodeFailSilent(clientZkWatcher, node);<a name="line.100"></a>
+<span class="sourceLineNo">101</span>      }<a name="line.101"></a>
+<span class="sourceLineNo">102</span>    } catch (KeeperException e) {<a name="line.102"></a>
+<span class="sourceLineNo">103</span>      server.abort("Unexpected exception during initialization, aborting", e);<a name="line.103"></a>
+<span class="sourceLineNo">104</span>    }<a name="line.104"></a>
+<span class="sourceLineNo">105</span>  }<a name="line.105"></a>
+<span class="sourceLineNo">106</span><a name="line.106"></a>
+<span class="sourceLineNo">107</span>  /**<a name="line.107"></a>
+<span class="sourceLineNo">108</span>   * Update the value of the single element in queue if any, or else insert.<a name="line.108"></a>
+<span class="sourceLineNo">109</span>   * &lt;p/&gt;<a name="line.109"></a>
+<span class="sourceLineNo">110</span>   * We only need to synchronize the latest znode value to client ZK rather than synchronize each<a name="line.110"></a>
+<span class="sourceLineNo">111</span>   * time<a name="line.111"></a>
+<span class="sourceLineNo">112</span>   * @param data the data to write to queue<a name="line.112"></a>
+<span class="sourceLineNo">113</span>   */<a name="line.113"></a>
+<span class="sourceLineNo">114</span>  private void upsertQueue(String node, byte[] data) {<a name="line.114"></a>
+<span class="sourceLineNo">115</span>    BlockingQueue&lt;byte[]&gt; queue = queues.get(node);<a name="line.115"></a>
+<span class="sourceLineNo">116</span>    synchronized (queue) {<a name="line.116"></a>
+<span class="sourceLineNo">117</span>      queue.poll();<a name="line.117"></a>
+<span class="sourceLineNo">118</span>      queue.offer(data);<a name="line.118"></a>
+<span class="sourceLineNo">119</span>    }<a name="line.119"></a>
+<span class="sourceLineNo">120</span>  }<a name="line.120"></a>
+<span class="sourceLineNo">121</span><a name="line.121"></a>
+<span class="sourceLineNo">122</span>  /**<a name="line.122"></a>
+<span class="sourceLineNo">123</span>   * Set data for client ZK and retry until succeed. Be very careful to prevent dead loop when<a name="line.123"></a>
+<span class="sourceLineNo">124</span>   * modifying this method<a name="line.124"></a>
+<span class="sourceLineNo">125</span>   * @param node the znode to set on client ZK<a name="line.125"></a>
+<span class="sourceLineNo">126</span>   * @param data the data to set to client ZK<a name="line.126"></a>
+<span class="sourceLineNo">127</span>   * @throws InterruptedException if the thread is interrupted during process<a name="line.127"></a>
+<span class="sourceLineNo">128</span>   */<a name="line.128"></a>
+<span class="sourceLineNo">129</span>  private final void setDataForClientZkUntilSuccess(String node, byte[] data)<a name="line.129"></a>
+<span class="sourceLineNo">130</span>      throws InterruptedException {<a name="line.130"></a>
+<span class="sourceLineNo">131</span>    while (!server.isStopped()) {<a name="line.131"></a>
+<span class="sourceLineNo">132</span>      try {<a name="line.132"></a>
+<span class="sourceLineNo">133</span>        LOG.debug("Set data for remote " + node + ", client zk wather: " + clientZkWatcher);<a name="line.133"></a>
+<span class="sourceLineNo">134</span>        ZKUtil.setData(clientZkWatcher, node, data);<a name="line.134"></a>
+<span class="sourceLineNo">135</span>        break;<a name="line.135"></a>
+<span class="sourceLineNo">136</span>      } catch (KeeperException.NoNodeException nne) {<a name="line.136"></a>
+<span class="sourceLineNo">137</span>        // Node doesn't exist, create it and set value<a name="line.137"></a>
+<span class="sourceLineNo">138</span>        try {<a name="line.138"></a>
+<span class="sourceLineNo">139</span>          ZKUtil.createNodeIfNotExistsNoWatch(clientZkWatcher, node, data, CreateMode.PERSISTENT);<a name="line.139"></a>
+<span class="sourceLineNo">140</span>          break;<a name="line.140"></a>
+<span class="sourceLineNo">141</span>        } catch (KeeperException.ConnectionLossException<a name="line.141"></a>
+<span class="sourceLineNo">142</span>            | KeeperException.SessionExpiredException ee) {<a name="line.142"></a>
+<span class="sourceLineNo">143</span>          reconnectAfterExpiration();<a name="line.143"></a>
+<span class="sourceLineNo">144</span>        } catch (KeeperException e) {<a name="line.144"></a>
+<span class="sourceLineNo">145</span>          LOG.warn(<a name="line.145"></a>
+<span class="sourceLineNo">146</span>            "Failed to create znode " + node + " due to: " + e.getMessage() + ", will retry later");<a name="line.146"></a>
+<span class="sourceLineNo">147</span>        }<a name="line.147"></a>
+<span class="sourceLineNo">148</span>      } catch (KeeperException.ConnectionLossException<a name="line.148"></a>
+<span class="sourceLineNo">149</span>          | KeeperException.SessionExpiredException ee) {<a name="line.149"></a>
+<span class="sourceLineNo">150</span>        reconnectAfterExpiration();<a name="line.150"></a>
+<span class="sourceLineNo">151</span>      } catch (KeeperException e) {<a name="line.151"></a>
+<span class="sourceLineNo">152</span>        LOG.debug("Failed to set data to client ZK, will retry later", e);<a name="line.152"></a>
+<span class="sourceLineNo">153</span>      }<a name="line.153"></a>
+<span class="sourceLineNo">154</span>      Threads.sleep(HConstants.SOCKET_RETRY_WAIT_MS);<a name="line.154"></a>
+<span class="sourceLineNo">155</span>    }<a name="line.155"></a>
+<span class="sourceLineNo">156</span>  }<a name="line.156"></a>
+<span class="sourceLineNo">157</span><a name="line.157"></a>
+<span class="sourceLineNo">158</span>  private final void reconnectAfterExpiration() throws InterruptedException {<a name="line.158"></a>
+<span class="sourceLineNo">159</span>    LOG.warn("ZK session expired or lost. Retry a new connection...");<a name="line.159"></a>
+<span class="sourceLineNo">160</span>    try {<a name="line.160"></a>
+<span class="sourceLineNo">161</span>      clientZkWatcher.reconnectAfterExpiration();<a name="line.161"></a>
+<span class="sourceLineNo">162</span>    } catch (IOException | KeeperException e) {<a name="line.162"></a>
+<span class="sourceLineNo">163</span>      LOG.warn("Failed to reconnect to client zk after session expiration, will retry later", e);<a name="line.163"></a>
+<span class="sourceLineNo">164</span>    }<a name="line.164"></a>
+<span class="sourceLineNo">165</span>  }<a name="line.165"></a>
+<span class="sourceLineNo">166</span><a name="line.166"></a>
+<span class="sourceLineNo">167</span>  @Override<a name="line.167"></a>
+<span class="sourceLineNo">168</span>  public void nodeCreated(String path) {<a name="line.168"></a>
+<span class="sourceLineNo">169</span>    if (!validate(path)) {<a name="line.169"></a>
+<span class="sourceLineNo">170</span>      return;<a name="line.170"></a>
+<span class="sourceLineNo">171</span>    }<a name="line.171"></a>
+<span class="sourceLineNo">172</span>    try {<a name="line.172"></a>
+<span class="sourceLineNo">173</span>      byte[] data = ZKUtil.getDataAndWatch(watcher, path);<a name="line.173"></a>
+<span class="sourceLineNo">174</span>      upsertQueue(path, data);<a name="line.174"></a>
+<span class="sourceLineNo">175</span>    } catch (KeeperException e) {<a name="line.175"></a>
+<span class="sourceLineNo">176</span>      LOG.warn("Unexpected exception handling nodeCreated event", e);<a name="line.176"></a>
+<span class="sourceLineNo">177</span>    }<a name="line.177"></a>
+<span class="sourceLineNo">178</span>  }<a name="line.178"></a>
+<span class="sourceLineNo">179</span><a name="line.179"></a>
+<span class="sourceLineNo">180</span>  @Override<a name="line.180"></a>
+<span class="sourceLineNo">181</span>  public void nodeDataChanged(String path) {<a name="line.181"></a>
+<span class="sourceLineNo">182</span>    if (validate(path)) {<a name="line.182"></a>
+<span class="sourceLineNo">183</span>      nodeCreated(path);<a name="line.183"></a>
+<span class="sourceLineNo">184</span>    }<a name="line.184"></a>
+<span class="sourceLineNo">185</span>  }<a name="line.185"></a>
+<span class="sourceLineNo">186</span><a name="line.186"></a>
+<span class="sourceLineNo">187</span>  @Override<a name="line.187"></a>
+<span class="sourceLineNo">188</span>  public synchronized void nodeDeleted(String path) {<a name="line.188"></a>
+<span class="sourceLineNo">189</span>    if (validate(path)) {<a name="line.189"></a>
+<span class="sourceLineNo">190</span>      try {<a name="line.190"></a>
+<span class="sourceLineNo">191</span>        if (ZKUtil.watchAndCheckExists(watcher, path)) {<a name="line.191"></a>
+<span class="sourceLineNo">192</span>          nodeCreated(path);<a name="line.192"></a>
+<span class="sourceLineNo">193</span>        }<a name="line.193"></a>
+<span class="sourceLineNo">194</span>      } catch (KeeperException e) {<a name="line.194"></a>
+<span class="sourceLineNo">195</span>        LOG.warn("Unexpected exception handling nodeDeleted event for path: " + path, e);<a name="line.195"></a>
+<span class="sourceLineNo">196</span>      }<a name="line.196"></a>
+<span class="sourceLineNo">197</span>    }<a name="line.197"></a>
+<span class="sourceLineNo">198</span>  }<a name="line.198"></a>
+<span class="sourceLineNo">199</span><a name="line.199"></a>
+<span class="sourceLineNo">200</span>  /**<a name="line.200"></a>
+<span class="sourceLineNo">201</span>   * Validate whether a znode path is watched by us<a name="line.201"></a>
+<span class="sourceLineNo">202</span>   * @param path the path to validate<a name="line.202"></a>
+<span class="sourceLineNo">203</span>   * @return true if the znode is watched by us<a name="line.203"></a>
+<span class="sourceLineNo">204</span>   */<a name="line.204"></a>
+<span class="sourceLineNo">205</span>  abstract boolean validate(String path);<a name="line.205"></a>
+<span class="sourceLineNo">206</span><a name="line.206"></a>
+<span class="sourceLineNo">207</span>  /**<a name="line.207"></a>
+<span class="sourceLineNo">208</span>   * @return the znode(s) to watch<a name="line.208"></a>
+<span class="sourceLineNo">209</span>   */<a name="line.209"></a>
+<span class="sourceLineNo">210</span>  abstract Collection&lt;String&gt; getNodesToWatch();<a name="line.210"></a>
+<span class="sourceLineNo">211</span><a name="line.211"></a>
+<span class="sourceLineNo">212</span>  /**<a name="line.212"></a>
+<span class="sourceLineNo">213</span>   * Thread to synchronize znode data to client ZK cluster<a name="line.213"></a>
+<span class="sourceLineNo">214</span>   */<a name="line.214"></a>
+<span class="sourceLineNo">215</span>  class ClientZkUpdater extends Thread {<a name="line.215"></a>
+<span class="sourceLineNo">216</span>    final String znode;<a name="line.216"></a>
+<span class="sourceLineNo">217</span>    final BlockingQueue&lt;byte[]&gt; queue;<a name="line.217"></a>
+<span class="sourceLineNo">218</span><a name="line.218"></a>
+<span class="sourceLineNo">219</span>    public ClientZkUpdater(String znode, BlockingQueue&lt;byte[]&gt; queue) {<a name="line.219"></a>
+<span class="sourceLineNo">220</span>      this.znode = znode;<a name="line.220"></a>
+<span class="sourceLineNo">221</span>      this.queue = queue;<a name="line.221"></a>
+<span class="sourceLineNo">222</span>      setName("ClientZKUpdater-" + znode);<a name="line.222"></a>
+<span class="sourceLineNo">223</span>    }<a name="line.223"></a>
+<span class="sourceLineNo">224</span><a name="line.224"></a>
+<span class="sourceLineNo">225</span>    @Override<a name="line.225"></a>
+<span class="sourceLineNo">226</span>    public void run() {<a name="line.226"></a>
+<span class="sourceLineNo">227</span>      while (!server.isStopped()) {<a name="line.227"></a>
+<span class="sourceLineNo">228</span>        try {<a name="line.228"></a>
+<span class="sourceLineNo">229</span>          byte[] data = queue.take();<a name="line.229"></a>
+<span class="sourceLineNo">230</span>          setDataForClientZkUntilSuccess(znode, data);<a name="line.230"></a>
+<span class="sourceLineNo">231</span>        } catch (InterruptedException e) {<a name="line.231"></a>
+<span class="sourceLineNo">232</span>          if (LOG.isDebugEnabled()) {<a name="line.232"></a>
+<span class="sourceLineNo">233</span>            LOG.debug(<a name="line.233"></a>
+<span class="sourceLineNo">234</span>              "Interrupted while checking whether need to update meta location to client zk");<a name="line.234"></a>
+<span class="sourceLineNo">235</span>          }<a name="line.235"></a>
+<span class="sourceLineNo">236</span>          Thread.currentThread().interrupt();<a name="line.236"></a>
+<span class="sourceLineNo">237</span>          break;<a name="line.237"></a>
+<span class="sourceLineNo">238</span>        }<a name="line.238"></a>
+<span class="sourceLineNo">239</span>      }<a name="line.239"></a>
+<span class="sourceLineNo">240</span>    }<a name="line.240"></a>
+<span class="sourceLineNo">241</span>  }<a name="line.241"></a>
+<span class="sourceLineNo">242</span>}<a name="line.242"></a>
 
 
 

http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1facf1d3/devapidocs/src-html/org/apache/hadoop/hbase/net/Address.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/net/Address.html b/devapidocs/src-html/org/apache/hadoop/hbase/net/Address.html
index 66aba38..c893aec 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/net/Address.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/net/Address.html
@@ -25,7 +25,7 @@
 <span class="sourceLineNo">017</span> */<a name="line.17"></a>
 <span class="sourceLineNo">018</span>package org.apache.hadoop.hbase.net;<a name="line.18"></a>
 <span class="sourceLineNo">019</span><a name="line.19"></a>
-<span class="sourceLineNo">020</span>import org.apache.commons.lang.StringUtils;<a name="line.20"></a>
+<span class="sourceLineNo">020</span>import org.apache.commons.lang3.StringUtils;<a name="line.20"></a>
 <span class="sourceLineNo">021</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.21"></a>
 <span class="sourceLineNo">022</span><a name="line.22"></a>
 <span class="sourceLineNo">023</span>import org.apache.hbase.thirdparty.com.google.common.net.HostAndPort;<a name="line.23"></a>

http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1facf1d3/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.CacheKey.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.CacheKey.html b/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.CacheKey.html
index 8d7d4b7..30fe071 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.CacheKey.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.CacheKey.html
@@ -27,7 +27,7 @@
 <span class="sourceLineNo">019</span>import java.util.Objects;<a name="line.19"></a>
 <span class="sourceLineNo">020</span>import java.util.concurrent.ConcurrentHashMap;<a name="line.20"></a>
 <span class="sourceLineNo">021</span><a name="line.21"></a>
-<span class="sourceLineNo">022</span>import org.apache.commons.lang.builder.HashCodeBuilder;<a name="line.22"></a>
+<span class="sourceLineNo">022</span>import org.apache.commons.lang3.builder.HashCodeBuilder;<a name="line.22"></a>
 <span class="sourceLineNo">023</span>import org.apache.hadoop.conf.Configuration;<a name="line.23"></a>
 <span class="sourceLineNo">024</span>import org.apache.hadoop.fs.FileSystem;<a name="line.24"></a>
 <span class="sourceLineNo">025</span>import org.apache.hadoop.hbase.TableName;<a name="line.25"></a>

http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1facf1d3/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.html b/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.html
index 8d7d4b7..30fe071 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.html
@@ -27,7 +27,7 @@
 <span class="sourceLineNo">019</span>import java.util.Objects;<a name="line.19"></a>
 <span class="sourceLineNo">020</span>import java.util.concurrent.ConcurrentHashMap;<a name="line.20"></a>
 <span class="sourceLineNo">021</span><a name="line.21"></a>
-<span class="sourceLineNo">022</span>import org.apache.commons.lang.builder.HashCodeBuilder;<a name="line.22"></a>
+<span class="sourceLineNo">022</span>import org.apache.commons.lang3.builder.HashCodeBuilder;<a name="line.22"></a>
 <span class="sourceLineNo">023</span>import org.apache.hadoop.conf.Configuration;<a name="line.23"></a>
 <span class="sourceLineNo">024</span>import org.apache.hadoop.fs.FileSystem;<a name="line.24"></a>
 <span class="sourceLineNo">025</span>import org.apache.hadoop.hbase.TableName;<a name="line.25"></a>