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| <pre><span class="source-line-no">001</span><span id="line-1">/*</span> |
| <span class="source-line-no">002</span><span id="line-2"> * Licensed to the Apache Software Foundation (ASF) under one</span> |
| <span class="source-line-no">003</span><span id="line-3"> * or more contributor license agreements. See the NOTICE file</span> |
| <span class="source-line-no">004</span><span id="line-4"> * distributed with this work for additional information</span> |
| <span class="source-line-no">005</span><span id="line-5"> * regarding copyright ownership. The ASF licenses this file</span> |
| <span class="source-line-no">006</span><span id="line-6"> * to you under the Apache License, Version 2.0 (the</span> |
| <span class="source-line-no">007</span><span id="line-7"> * "License"); you may not use this file except in compliance</span> |
| <span class="source-line-no">008</span><span id="line-8"> * with the License. You may obtain a copy of the License at</span> |
| <span class="source-line-no">009</span><span id="line-9"> *</span> |
| <span class="source-line-no">010</span><span id="line-10"> * http://www.apache.org/licenses/LICENSE-2.0</span> |
| <span class="source-line-no">011</span><span id="line-11"> *</span> |
| <span class="source-line-no">012</span><span id="line-12"> * Unless required by applicable law or agreed to in writing, software</span> |
| <span class="source-line-no">013</span><span id="line-13"> * distributed under the License is distributed on an "AS IS" BASIS,</span> |
| <span class="source-line-no">014</span><span id="line-14"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span> |
| <span class="source-line-no">015</span><span id="line-15"> * See the License for the specific language governing permissions and</span> |
| <span class="source-line-no">016</span><span id="line-16"> * limitations under the License.</span> |
| <span class="source-line-no">017</span><span id="line-17"> */</span> |
| <span class="source-line-no">018</span><span id="line-18">package org.apache.hadoop.hbase.regionserver;</span> |
| <span class="source-line-no">019</span><span id="line-19"></span> |
| <span class="source-line-no">020</span><span id="line-20">import java.io.IOException;</span> |
| <span class="source-line-no">021</span><span id="line-21">import java.lang.reflect.Field;</span> |
| <span class="source-line-no">022</span><span id="line-22">import java.util.HashMap;</span> |
| <span class="source-line-no">023</span><span id="line-23">import java.util.Map;</span> |
| <span class="source-line-no">024</span><span id="line-24">import org.apache.hadoop.conf.Configuration;</span> |
| <span class="source-line-no">025</span><span id="line-25">import org.apache.hadoop.fs.FileSystem;</span> |
| <span class="source-line-no">026</span><span id="line-26">import org.apache.hadoop.hbase.HBaseConfiguration;</span> |
| <span class="source-line-no">027</span><span id="line-27">import org.apache.hadoop.hbase.Stoppable;</span> |
| <span class="source-line-no">028</span><span id="line-28">import org.apache.hadoop.hbase.log.HBaseMarkers;</span> |
| <span class="source-line-no">029</span><span id="line-29">import org.apache.hadoop.hbase.util.ShutdownHookManager;</span> |
| <span class="source-line-no">030</span><span id="line-30">import org.apache.hadoop.hbase.util.Threads;</span> |
| <span class="source-line-no">031</span><span id="line-31">import org.apache.yetus.audience.InterfaceAudience;</span> |
| <span class="source-line-no">032</span><span id="line-32">import org.slf4j.Logger;</span> |
| <span class="source-line-no">033</span><span id="line-33">import org.slf4j.LoggerFactory;</span> |
| <span class="source-line-no">034</span><span id="line-34"></span> |
| <span class="source-line-no">035</span><span id="line-35">/**</span> |
| <span class="source-line-no">036</span><span id="line-36"> * Manage regionserver shutdown hooks.</span> |
| <span class="source-line-no">037</span><span id="line-37"> * @see #install(Configuration, FileSystem, Stoppable, Thread)</span> |
| <span class="source-line-no">038</span><span id="line-38"> */</span> |
| <span class="source-line-no">039</span><span id="line-39">@InterfaceAudience.Private</span> |
| <span class="source-line-no">040</span><span id="line-40">public class ShutdownHook {</span> |
| <span class="source-line-no">041</span><span id="line-41"> private static final Logger LOG = LoggerFactory.getLogger(ShutdownHook.class);</span> |
| <span class="source-line-no">042</span><span id="line-42"> private static final String CLIENT_FINALIZER_DATA_METHOD = "clientFinalizer";</span> |
| <span class="source-line-no">043</span><span id="line-43"></span> |
| <span class="source-line-no">044</span><span id="line-44"> /**</span> |
| <span class="source-line-no">045</span><span id="line-45"> * Key for boolean configuration whose default is true.</span> |
| <span class="source-line-no">046</span><span id="line-46"> */</span> |
| <span class="source-line-no">047</span><span id="line-47"> public static final String RUN_SHUTDOWN_HOOK = "hbase.shutdown.hook";</span> |
| <span class="source-line-no">048</span><span id="line-48"></span> |
| <span class="source-line-no">049</span><span id="line-49"> /**</span> |
| <span class="source-line-no">050</span><span id="line-50"> * Key for a long configuration on how much time to wait on the fs shutdown hook. Default is 30</span> |
| <span class="source-line-no">051</span><span id="line-51"> * seconds.</span> |
| <span class="source-line-no">052</span><span id="line-52"> */</span> |
| <span class="source-line-no">053</span><span id="line-53"> public static final String FS_SHUTDOWN_HOOK_WAIT = "hbase.fs.shutdown.hook.wait";</span> |
| <span class="source-line-no">054</span><span id="line-54"></span> |
| <span class="source-line-no">055</span><span id="line-55"> /**</span> |
| <span class="source-line-no">056</span><span id="line-56"> * A place for keeping track of all the filesystem shutdown hooks that need to be executed after</span> |
| <span class="source-line-no">057</span><span id="line-57"> * the last regionserver referring to a given filesystem stops. We keep track of the # of</span> |
| <span class="source-line-no">058</span><span id="line-58"> * regionserver references in values of the map.</span> |
| <span class="source-line-no">059</span><span id="line-59"> */</span> |
| <span class="source-line-no">060</span><span id="line-60"> private final static Map<Runnable, Integer> fsShutdownHooks = new HashMap<>();</span> |
| <span class="source-line-no">061</span><span id="line-61"></span> |
| <span class="source-line-no">062</span><span id="line-62"> /**</span> |
| <span class="source-line-no">063</span><span id="line-63"> * Install a shutdown hook that calls stop on the passed Stoppable and then thread joins against</span> |
| <span class="source-line-no">064</span><span id="line-64"> * the passed <code>threadToJoin</code>. When this thread completes, it then runs the hdfs thread</span> |
| <span class="source-line-no">065</span><span id="line-65"> * (This install removes the hdfs shutdown hook keeping a handle on it to run it after</span> |
| <span class="source-line-no">066</span><span id="line-66"> * <code>threadToJoin</code> has stopped).</span> |
| <span class="source-line-no">067</span><span id="line-67"> * <p></span> |
| <span class="source-line-no">068</span><span id="line-68"> * To suppress all shutdown hook handling -- both the running of the regionserver hook and of the</span> |
| <span class="source-line-no">069</span><span id="line-69"> * hdfs hook code -- set {@link ShutdownHook#RUN_SHUTDOWN_HOOK} in {@link Configuration} to</span> |
| <span class="source-line-no">070</span><span id="line-70"> * <code>false</code>. This configuration value is checked when the hook code runs.</span> |
| <span class="source-line-no">071</span><span id="line-71"> * @param fs Instance of Filesystem used by the RegionServer</span> |
| <span class="source-line-no">072</span><span id="line-72"> * @param stop Installed shutdown hook will call stop against this passed</span> |
| <span class="source-line-no">073</span><span id="line-73"> * <code>Stoppable</code> instance.</span> |
| <span class="source-line-no">074</span><span id="line-74"> * @param threadToJoin After calling stop on <code>stop</code> will then join this thread.</span> |
| <span class="source-line-no">075</span><span id="line-75"> */</span> |
| <span class="source-line-no">076</span><span id="line-76"> public static void install(final Configuration conf, final FileSystem fs, final Stoppable stop,</span> |
| <span class="source-line-no">077</span><span id="line-77"> final Thread threadToJoin) {</span> |
| <span class="source-line-no">078</span><span id="line-78"> Runnable fsShutdownHook = suppressHdfsShutdownHook(fs);</span> |
| <span class="source-line-no">079</span><span id="line-79"> Thread t = new ShutdownHookThread(conf, stop, threadToJoin, fsShutdownHook);</span> |
| <span class="source-line-no">080</span><span id="line-80"> ShutdownHookManager.affixShutdownHook(t, 0);</span> |
| <span class="source-line-no">081</span><span id="line-81"> LOG.debug("Installed shutdown hook thread: " + t.getName());</span> |
| <span class="source-line-no">082</span><span id="line-82"> }</span> |
| <span class="source-line-no">083</span><span id="line-83"></span> |
| <span class="source-line-no">084</span><span id="line-84"> /*</span> |
| <span class="source-line-no">085</span><span id="line-85"> * Thread run by shutdown hook.</span> |
| <span class="source-line-no">086</span><span id="line-86"> */</span> |
| <span class="source-line-no">087</span><span id="line-87"> private static class ShutdownHookThread extends Thread {</span> |
| <span class="source-line-no">088</span><span id="line-88"> private final Stoppable stop;</span> |
| <span class="source-line-no">089</span><span id="line-89"> private final Thread threadToJoin;</span> |
| <span class="source-line-no">090</span><span id="line-90"> private final Runnable fsShutdownHook;</span> |
| <span class="source-line-no">091</span><span id="line-91"> private final Configuration conf;</span> |
| <span class="source-line-no">092</span><span id="line-92"></span> |
| <span class="source-line-no">093</span><span id="line-93"> ShutdownHookThread(final Configuration conf, final Stoppable stop, final Thread threadToJoin,</span> |
| <span class="source-line-no">094</span><span id="line-94"> final Runnable fsShutdownHook) {</span> |
| <span class="source-line-no">095</span><span id="line-95"> super("Shutdownhook:" + threadToJoin.getName());</span> |
| <span class="source-line-no">096</span><span id="line-96"> this.stop = stop;</span> |
| <span class="source-line-no">097</span><span id="line-97"> this.threadToJoin = threadToJoin;</span> |
| <span class="source-line-no">098</span><span id="line-98"> this.conf = conf;</span> |
| <span class="source-line-no">099</span><span id="line-99"> this.fsShutdownHook = fsShutdownHook;</span> |
| <span class="source-line-no">100</span><span id="line-100"> }</span> |
| <span class="source-line-no">101</span><span id="line-101"></span> |
| <span class="source-line-no">102</span><span id="line-102"> @Override</span> |
| <span class="source-line-no">103</span><span id="line-103"> public void run() {</span> |
| <span class="source-line-no">104</span><span id="line-104"> boolean b = this.conf.getBoolean(RUN_SHUTDOWN_HOOK, true);</span> |
| <span class="source-line-no">105</span><span id="line-105"> LOG.info("Shutdown hook starting; " + RUN_SHUTDOWN_HOOK + "=" + b + "; fsShutdownHook="</span> |
| <span class="source-line-no">106</span><span id="line-106"> + this.fsShutdownHook);</span> |
| <span class="source-line-no">107</span><span id="line-107"> if (b) {</span> |
| <span class="source-line-no">108</span><span id="line-108"> this.stop.stop("Shutdown hook");</span> |
| <span class="source-line-no">109</span><span id="line-109"> Threads.shutdown(this.threadToJoin);</span> |
| <span class="source-line-no">110</span><span id="line-110"> if (this.fsShutdownHook != null) {</span> |
| <span class="source-line-no">111</span><span id="line-111"> synchronized (fsShutdownHooks) {</span> |
| <span class="source-line-no">112</span><span id="line-112"> int refs = fsShutdownHooks.get(fsShutdownHook);</span> |
| <span class="source-line-no">113</span><span id="line-113"> if (refs == 1) {</span> |
| <span class="source-line-no">114</span><span id="line-114"> LOG.info("Starting fs shutdown hook thread.");</span> |
| <span class="source-line-no">115</span><span id="line-115"> Thread fsShutdownHookThread = (fsShutdownHook instanceof Thread)</span> |
| <span class="source-line-no">116</span><span id="line-116"> ? (Thread) fsShutdownHook</span> |
| <span class="source-line-no">117</span><span id="line-117"> : new Thread(fsShutdownHook,</span> |
| <span class="source-line-no">118</span><span id="line-118"> fsShutdownHook.getClass().getSimpleName() + "-shutdown-hook");</span> |
| <span class="source-line-no">119</span><span id="line-119"> fsShutdownHookThread.start();</span> |
| <span class="source-line-no">120</span><span id="line-120"> Threads.shutdown(fsShutdownHookThread,</span> |
| <span class="source-line-no">121</span><span id="line-121"> this.conf.getLong(FS_SHUTDOWN_HOOK_WAIT, 30000));</span> |
| <span class="source-line-no">122</span><span id="line-122"> }</span> |
| <span class="source-line-no">123</span><span id="line-123"> if (refs > 0) {</span> |
| <span class="source-line-no">124</span><span id="line-124"> fsShutdownHooks.put(fsShutdownHook, refs - 1);</span> |
| <span class="source-line-no">125</span><span id="line-125"> }</span> |
| <span class="source-line-no">126</span><span id="line-126"> }</span> |
| <span class="source-line-no">127</span><span id="line-127"> }</span> |
| <span class="source-line-no">128</span><span id="line-128"> }</span> |
| <span class="source-line-no">129</span><span id="line-129"> LOG.info("Shutdown hook finished.");</span> |
| <span class="source-line-no">130</span><span id="line-130"> }</span> |
| <span class="source-line-no">131</span><span id="line-131"> }</span> |
| <span class="source-line-no">132</span><span id="line-132"></span> |
| <span class="source-line-no">133</span><span id="line-133"> /*</span> |
| <span class="source-line-no">134</span><span id="line-134"> * So, HDFS keeps a static map of all FS instances. In order to make sure things are cleaned up on</span> |
| <span class="source-line-no">135</span><span id="line-135"> * our way out, it also creates a shutdown hook so that all filesystems can be closed when the</span> |
| <span class="source-line-no">136</span><span id="line-136"> * process is terminated; it calls FileSystem.closeAll. This inconveniently runs concurrently with</span> |
| <span class="source-line-no">137</span><span id="line-137"> * our own shutdown handler, and therefore causes all the filesystems to be closed before the</span> |
| <span class="source-line-no">138</span><span id="line-138"> * server can do all its necessary cleanup. <p>The dirty reflection in this method sneaks into the</span> |
| <span class="source-line-no">139</span><span id="line-139"> * FileSystem class and grabs the shutdown hook, removes it from the list of active shutdown</span> |
| <span class="source-line-no">140</span><span id="line-140"> * hooks, and returns the hook for the caller to run at its convenience. <p>This seems quite</span> |
| <span class="source-line-no">141</span><span id="line-141"> * fragile and susceptible to breaking if Hadoop changes anything about the way this cleanup is</span> |
| <span class="source-line-no">142</span><span id="line-142"> * managed. Keep an eye on things.</span> |
| <span class="source-line-no">143</span><span id="line-143"> * @return The fs shutdown hook</span> |
| <span class="source-line-no">144</span><span id="line-144"> * @throws RuntimeException if we fail to find or grap the shutdown hook.</span> |
| <span class="source-line-no">145</span><span id="line-145"> */</span> |
| <span class="source-line-no">146</span><span id="line-146"> private static Runnable suppressHdfsShutdownHook(final FileSystem fs) {</span> |
| <span class="source-line-no">147</span><span id="line-147"> try {</span> |
| <span class="source-line-no">148</span><span id="line-148"> // This introspection has been updated to work for hadoop 0.20, 0.21 and for</span> |
| <span class="source-line-no">149</span><span id="line-149"> // cloudera 0.20. 0.21 and cloudera 0.20 both have hadoop-4829. With the</span> |
| <span class="source-line-no">150</span><span id="line-150"> // latter in place, things are a little messy in that there are now two</span> |
| <span class="source-line-no">151</span><span id="line-151"> // instances of the data member clientFinalizer; an uninstalled one in</span> |
| <span class="source-line-no">152</span><span id="line-152"> // FileSystem and one in the innner class named Cache that actually gets</span> |
| <span class="source-line-no">153</span><span id="line-153"> // registered as a shutdown hook. If the latter is present, then we are</span> |
| <span class="source-line-no">154</span><span id="line-154"> // on 0.21 or cloudera patched 0.20.</span> |
| <span class="source-line-no">155</span><span id="line-155"> Runnable hdfsClientFinalizer = null;</span> |
| <span class="source-line-no">156</span><span id="line-156"> // Look into the FileSystem#Cache class for clientFinalizer</span> |
| <span class="source-line-no">157</span><span id="line-157"> Class<?>[] classes = FileSystem.class.getDeclaredClasses();</span> |
| <span class="source-line-no">158</span><span id="line-158"> Class<?> cache = null;</span> |
| <span class="source-line-no">159</span><span id="line-159"> for (Class<?> c : classes) {</span> |
| <span class="source-line-no">160</span><span id="line-160"> if (c.getSimpleName().equals("Cache")) {</span> |
| <span class="source-line-no">161</span><span id="line-161"> cache = c;</span> |
| <span class="source-line-no">162</span><span id="line-162"> break;</span> |
| <span class="source-line-no">163</span><span id="line-163"> }</span> |
| <span class="source-line-no">164</span><span id="line-164"> }</span> |
| <span class="source-line-no">165</span><span id="line-165"></span> |
| <span class="source-line-no">166</span><span id="line-166"> if (cache == null) {</span> |
| <span class="source-line-no">167</span><span id="line-167"> throw new RuntimeException(</span> |
| <span class="source-line-no">168</span><span id="line-168"> "This should not happen. Could not find the cache class in FileSystem.");</span> |
| <span class="source-line-no">169</span><span id="line-169"> }</span> |
| <span class="source-line-no">170</span><span id="line-170"></span> |
| <span class="source-line-no">171</span><span id="line-171"> Field field = null;</span> |
| <span class="source-line-no">172</span><span id="line-172"> try {</span> |
| <span class="source-line-no">173</span><span id="line-173"> field = cache.getDeclaredField(CLIENT_FINALIZER_DATA_METHOD);</span> |
| <span class="source-line-no">174</span><span id="line-174"> } catch (NoSuchFieldException e) {</span> |
| <span class="source-line-no">175</span><span id="line-175"> // We can get here if the Cache class does not have a clientFinalizer</span> |
| <span class="source-line-no">176</span><span id="line-176"> // instance: i.e. we're running on straight 0.20 w/o hadoop-4829.</span> |
| <span class="source-line-no">177</span><span id="line-177"> }</span> |
| <span class="source-line-no">178</span><span id="line-178"> if (field != null) {</span> |
| <span class="source-line-no">179</span><span id="line-179"> field.setAccessible(true);</span> |
| <span class="source-line-no">180</span><span id="line-180"> Field cacheField = FileSystem.class.getDeclaredField("CACHE");</span> |
| <span class="source-line-no">181</span><span id="line-181"> cacheField.setAccessible(true);</span> |
| <span class="source-line-no">182</span><span id="line-182"> Object cacheInstance = cacheField.get(fs);</span> |
| <span class="source-line-no">183</span><span id="line-183"> hdfsClientFinalizer = (Runnable) field.get(cacheInstance);</span> |
| <span class="source-line-no">184</span><span id="line-184"> } else {</span> |
| <span class="source-line-no">185</span><span id="line-185"> // Then we didnt' find clientFinalizer in Cache. Presume clean 0.20 hadoop.</span> |
| <span class="source-line-no">186</span><span id="line-186"> field = FileSystem.class.getDeclaredField(CLIENT_FINALIZER_DATA_METHOD);</span> |
| <span class="source-line-no">187</span><span id="line-187"> field.setAccessible(true);</span> |
| <span class="source-line-no">188</span><span id="line-188"> hdfsClientFinalizer = (Runnable) field.get(null);</span> |
| <span class="source-line-no">189</span><span id="line-189"> }</span> |
| <span class="source-line-no">190</span><span id="line-190"> if (hdfsClientFinalizer == null) {</span> |
| <span class="source-line-no">191</span><span id="line-191"> throw new RuntimeException("Client finalizer is null, can't suppress!");</span> |
| <span class="source-line-no">192</span><span id="line-192"> }</span> |
| <span class="source-line-no">193</span><span id="line-193"> synchronized (fsShutdownHooks) {</span> |
| <span class="source-line-no">194</span><span id="line-194"> boolean isFSCacheDisabled = fs.getConf().getBoolean("fs.hdfs.impl.disable.cache", false);</span> |
| <span class="source-line-no">195</span><span id="line-195"> if (</span> |
| <span class="source-line-no">196</span><span id="line-196"> !isFSCacheDisabled && !fsShutdownHooks.containsKey(hdfsClientFinalizer)</span> |
| <span class="source-line-no">197</span><span id="line-197"> && !ShutdownHookManager.deleteShutdownHook(hdfsClientFinalizer)</span> |
| <span class="source-line-no">198</span><span id="line-198"> ) {</span> |
| <span class="source-line-no">199</span><span id="line-199"> throw new RuntimeException(</span> |
| <span class="source-line-no">200</span><span id="line-200"> "Failed suppression of fs shutdown hook: " + hdfsClientFinalizer);</span> |
| <span class="source-line-no">201</span><span id="line-201"> }</span> |
| <span class="source-line-no">202</span><span id="line-202"> Integer refs = fsShutdownHooks.get(hdfsClientFinalizer);</span> |
| <span class="source-line-no">203</span><span id="line-203"> fsShutdownHooks.put(hdfsClientFinalizer, refs == null ? 1 : refs + 1);</span> |
| <span class="source-line-no">204</span><span id="line-204"> }</span> |
| <span class="source-line-no">205</span><span id="line-205"> return hdfsClientFinalizer;</span> |
| <span class="source-line-no">206</span><span id="line-206"> } catch (NoSuchFieldException nsfe) {</span> |
| <span class="source-line-no">207</span><span id="line-207"> LOG.error(HBaseMarkers.FATAL, "Couldn't find field 'clientFinalizer' in FileSystem!", nsfe);</span> |
| <span class="source-line-no">208</span><span id="line-208"> throw new RuntimeException("Failed to suppress HDFS shutdown hook");</span> |
| <span class="source-line-no">209</span><span id="line-209"> } catch (IllegalAccessException iae) {</span> |
| <span class="source-line-no">210</span><span id="line-210"> LOG.error(HBaseMarkers.FATAL, "Couldn't access field 'clientFinalizer' in FileSystem!", iae);</span> |
| <span class="source-line-no">211</span><span id="line-211"> throw new RuntimeException("Failed to suppress HDFS shutdown hook");</span> |
| <span class="source-line-no">212</span><span id="line-212"> }</span> |
| <span class="source-line-no">213</span><span id="line-213"> }</span> |
| <span class="source-line-no">214</span><span id="line-214"></span> |
| <span class="source-line-no">215</span><span id="line-215"> // Thread that does nothing. Used in below main testing.</span> |
| <span class="source-line-no">216</span><span id="line-216"> static class DoNothingThread extends Thread {</span> |
| <span class="source-line-no">217</span><span id="line-217"> DoNothingThread() {</span> |
| <span class="source-line-no">218</span><span id="line-218"> super("donothing");</span> |
| <span class="source-line-no">219</span><span id="line-219"> }</span> |
| <span class="source-line-no">220</span><span id="line-220"></span> |
| <span class="source-line-no">221</span><span id="line-221"> @Override</span> |
| <span class="source-line-no">222</span><span id="line-222"> public void run() {</span> |
| <span class="source-line-no">223</span><span id="line-223"> super.run();</span> |
| <span class="source-line-no">224</span><span id="line-224"> }</span> |
| <span class="source-line-no">225</span><span id="line-225"> }</span> |
| <span class="source-line-no">226</span><span id="line-226"></span> |
| <span class="source-line-no">227</span><span id="line-227"> // Stoppable with nothing to stop. Used below in main testing.</span> |
| <span class="source-line-no">228</span><span id="line-228"> static class DoNothingStoppable implements Stoppable {</span> |
| <span class="source-line-no">229</span><span id="line-229"> @Override</span> |
| <span class="source-line-no">230</span><span id="line-230"> public boolean isStopped() {</span> |
| <span class="source-line-no">231</span><span id="line-231"> // TODO Auto-generated method stub</span> |
| <span class="source-line-no">232</span><span id="line-232"> return false;</span> |
| <span class="source-line-no">233</span><span id="line-233"> }</span> |
| <span class="source-line-no">234</span><span id="line-234"></span> |
| <span class="source-line-no">235</span><span id="line-235"> @Override</span> |
| <span class="source-line-no">236</span><span id="line-236"> public void stop(String why) {</span> |
| <span class="source-line-no">237</span><span id="line-237"> // TODO Auto-generated method stub</span> |
| <span class="source-line-no">238</span><span id="line-238"> }</span> |
| <span class="source-line-no">239</span><span id="line-239"> }</span> |
| <span class="source-line-no">240</span><span id="line-240"></span> |
| <span class="source-line-no">241</span><span id="line-241"> /**</span> |
| <span class="source-line-no">242</span><span id="line-242"> * Main to test basic functionality. Run with clean hadoop 0.20 and hadoop 0.21 and cloudera</span> |
| <span class="source-line-no">243</span><span id="line-243"> * patched hadoop to make sure our shutdown hook handling works for all compbinations. Pass</span> |
| <span class="source-line-no">244</span><span id="line-244"> * '-Dhbase.shutdown.hook=false' to test turning off the running of shutdown hooks.</span> |
| <span class="source-line-no">245</span><span id="line-245"> */</span> |
| <span class="source-line-no">246</span><span id="line-246"> public static void main(final String[] args) throws IOException {</span> |
| <span class="source-line-no">247</span><span id="line-247"> Configuration conf = HBaseConfiguration.create();</span> |
| <span class="source-line-no">248</span><span id="line-248"> String prop = System.getProperty(RUN_SHUTDOWN_HOOK);</span> |
| <span class="source-line-no">249</span><span id="line-249"> if (prop != null) {</span> |
| <span class="source-line-no">250</span><span id="line-250"> conf.setBoolean(RUN_SHUTDOWN_HOOK, Boolean.parseBoolean(prop));</span> |
| <span class="source-line-no">251</span><span id="line-251"> }</span> |
| <span class="source-line-no">252</span><span id="line-252"> // Instantiate a FileSystem. This will register the fs shutdown hook.</span> |
| <span class="source-line-no">253</span><span id="line-253"> FileSystem fs = FileSystem.get(conf);</span> |
| <span class="source-line-no">254</span><span id="line-254"> Thread donothing = new DoNothingThread();</span> |
| <span class="source-line-no">255</span><span id="line-255"> donothing.start();</span> |
| <span class="source-line-no">256</span><span id="line-256"> ShutdownHook.install(conf, fs, new DoNothingStoppable(), donothing);</span> |
| <span class="source-line-no">257</span><span id="line-257"> }</span> |
| <span class="source-line-no">258</span><span id="line-258">}</span> |
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| </pre> |
| </div> |
| </main> |
| </body> |
| </html> |
