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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.procedure;</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.util.concurrent.Callable;</span> |
| <span class="source-line-no">022</span><span id="line-22">import java.util.concurrent.CountDownLatch;</span> |
| <span class="source-line-no">023</span><span id="line-23">import org.apache.hadoop.hbase.errorhandling.ForeignException;</span> |
| <span class="source-line-no">024</span><span id="line-24">import org.apache.hadoop.hbase.errorhandling.ForeignExceptionDispatcher;</span> |
| <span class="source-line-no">025</span><span id="line-25">import org.apache.hadoop.hbase.errorhandling.ForeignExceptionListener;</span> |
| <span class="source-line-no">026</span><span id="line-26">import org.apache.hadoop.hbase.errorhandling.ForeignExceptionSnare;</span> |
| <span class="source-line-no">027</span><span id="line-27">import org.apache.hadoop.hbase.errorhandling.TimeoutExceptionInjector;</span> |
| <span class="source-line-no">028</span><span id="line-28">import org.apache.yetus.audience.InterfaceAudience;</span> |
| <span class="source-line-no">029</span><span id="line-29">import org.apache.zookeeper.KeeperException;</span> |
| <span class="source-line-no">030</span><span id="line-30">import org.slf4j.Logger;</span> |
| <span class="source-line-no">031</span><span id="line-31">import org.slf4j.LoggerFactory;</span> |
| <span class="source-line-no">032</span><span id="line-32"></span> |
| <span class="source-line-no">033</span><span id="line-33">/**</span> |
| <span class="source-line-no">034</span><span id="line-34"> * Distributed procedure member's Subprocedure. A procedure is sarted on a ProcedureCoordinator</span> |
| <span class="source-line-no">035</span><span id="line-35"> * which communicates with ProcedureMembers who create and start its part of the Procedure. This sub</span> |
| <span class="source-line-no">036</span><span id="line-36"> * part is called a Subprocedure Users should subclass this and implement {@link #acquireBarrier()}</span> |
| <span class="source-line-no">037</span><span id="line-37"> * (get local barrier for this member), {@link #insideBarrier()} (execute while globally barriered</span> |
| <span class="source-line-no">038</span><span id="line-38"> * and release barrier) and {@link #cleanup(Exception)} (release state associated with</span> |
| <span class="source-line-no">039</span><span id="line-39"> * subprocedure.) When submitted to a ProcedureMember, the call method is executed in a separate</span> |
| <span class="source-line-no">040</span><span id="line-40"> * thread. Latches are use too block its progress and trigger continuations when barrier conditions</span> |
| <span class="source-line-no">041</span><span id="line-41"> * are met. Exception that makes it out of calls to {@link #acquireBarrier()} or</span> |
| <span class="source-line-no">042</span><span id="line-42"> * {@link #insideBarrier()} gets converted into {@link ForeignException}, which will get propagated</span> |
| <span class="source-line-no">043</span><span id="line-43"> * to the {@link ProcedureCoordinator}. There is a category of procedure (ex: online-snapshots), and</span> |
| <span class="source-line-no">044</span><span id="line-44"> * a user-specified instance-specific barrierName. (ex: snapshot121126).</span> |
| <span class="source-line-no">045</span><span id="line-45"> */</span> |
| <span class="source-line-no">046</span><span id="line-46">@InterfaceAudience.Private</span> |
| <span class="source-line-no">047</span><span id="line-47">abstract public class Subprocedure implements Callable<Void> {</span> |
| <span class="source-line-no">048</span><span id="line-48"> private static final Logger LOG = LoggerFactory.getLogger(Subprocedure.class);</span> |
| <span class="source-line-no">049</span><span id="line-49"></span> |
| <span class="source-line-no">050</span><span id="line-50"> // Name of the procedure</span> |
| <span class="source-line-no">051</span><span id="line-51"> final private String barrierName;</span> |
| <span class="source-line-no">052</span><span id="line-52"></span> |
| <span class="source-line-no">053</span><span id="line-53"> //</span> |
| <span class="source-line-no">054</span><span id="line-54"> // Execution state</span> |
| <span class="source-line-no">055</span><span id="line-55"> //</span> |
| <span class="source-line-no">056</span><span id="line-56"></span> |
| <span class="source-line-no">057</span><span id="line-57"> /** wait on before allowing the in barrier phase to proceed */</span> |
| <span class="source-line-no">058</span><span id="line-58"> private final CountDownLatch inGlobalBarrier;</span> |
| <span class="source-line-no">059</span><span id="line-59"> /** counted down when the Subprocedure has completed */</span> |
| <span class="source-line-no">060</span><span id="line-60"> private final CountDownLatch releasedLocalBarrier;</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"> // Error handling</span> |
| <span class="source-line-no">064</span><span id="line-64"> //</span> |
| <span class="source-line-no">065</span><span id="line-65"> /** monitor to check for errors */</span> |
| <span class="source-line-no">066</span><span id="line-66"> protected final ForeignExceptionDispatcher monitor;</span> |
| <span class="source-line-no">067</span><span id="line-67"> /** frequency to check for errors (ms) */</span> |
| <span class="source-line-no">068</span><span id="line-68"> protected final long wakeFrequency;</span> |
| <span class="source-line-no">069</span><span id="line-69"> protected final TimeoutExceptionInjector executionTimeoutTimer;</span> |
| <span class="source-line-no">070</span><span id="line-70"> protected final ProcedureMemberRpcs rpcs;</span> |
| <span class="source-line-no">071</span><span id="line-71"></span> |
| <span class="source-line-no">072</span><span id="line-72"> private volatile boolean complete = false;</span> |
| <span class="source-line-no">073</span><span id="line-73"></span> |
| <span class="source-line-no">074</span><span id="line-74"> /**</span> |
| <span class="source-line-no">075</span><span id="line-75"> * @param member reference to the member managing this subprocedure</span> |
| <span class="source-line-no">076</span><span id="line-76"> * @param procName name of the procedure this subprocedure is associated with</span> |
| <span class="source-line-no">077</span><span id="line-77"> * @param monitor notified if there is an error in the subprocedure</span> |
| <span class="source-line-no">078</span><span id="line-78"> * @param wakeFrequency time in millis to wake to check if there is an error via the monitor (in</span> |
| <span class="source-line-no">079</span><span id="line-79"> * milliseconds).</span> |
| <span class="source-line-no">080</span><span id="line-80"> * @param timeout time in millis that will trigger a subprocedure abort if it has not</span> |
| <span class="source-line-no">081</span><span id="line-81"> * completed</span> |
| <span class="source-line-no">082</span><span id="line-82"> */</span> |
| <span class="source-line-no">083</span><span id="line-83"> public Subprocedure(ProcedureMember member, String procName, ForeignExceptionDispatcher monitor,</span> |
| <span class="source-line-no">084</span><span id="line-84"> long wakeFrequency, long timeout) {</span> |
| <span class="source-line-no">085</span><span id="line-85"> // Asserts should be caught during unit testing</span> |
| <span class="source-line-no">086</span><span id="line-86"> assert member != null : "procedure member should be non-null";</span> |
| <span class="source-line-no">087</span><span id="line-87"> assert member.getRpcs() != null : "rpc handlers should be non-null";</span> |
| <span class="source-line-no">088</span><span id="line-88"> assert procName != null : "procedure name should be non-null";</span> |
| <span class="source-line-no">089</span><span id="line-89"> assert monitor != null : "monitor should be non-null";</span> |
| <span class="source-line-no">090</span><span id="line-90"></span> |
| <span class="source-line-no">091</span><span id="line-91"> // Default to a very large timeout</span> |
| <span class="source-line-no">092</span><span id="line-92"> this.rpcs = member.getRpcs();</span> |
| <span class="source-line-no">093</span><span id="line-93"> this.barrierName = procName;</span> |
| <span class="source-line-no">094</span><span id="line-94"> this.monitor = monitor;</span> |
| <span class="source-line-no">095</span><span id="line-95"> // forward any failures to coordinator. Since this is a dispatcher, resend loops should not be</span> |
| <span class="source-line-no">096</span><span id="line-96"> // possible.</span> |
| <span class="source-line-no">097</span><span id="line-97"> this.monitor.addListener(new ForeignExceptionListener() {</span> |
| <span class="source-line-no">098</span><span id="line-98"> @Override</span> |
| <span class="source-line-no">099</span><span id="line-99"> public void receive(ForeignException ee) {</span> |
| <span class="source-line-no">100</span><span id="line-100"> // if this is a notification from a remote source, just log</span> |
| <span class="source-line-no">101</span><span id="line-101"> if (ee.isRemote()) {</span> |
| <span class="source-line-no">102</span><span id="line-102"> LOG.debug("Was remote foreign exception, not redispatching error", ee);</span> |
| <span class="source-line-no">103</span><span id="line-103"> return;</span> |
| <span class="source-line-no">104</span><span id="line-104"> }</span> |
| <span class="source-line-no">105</span><span id="line-105"> // if this is a local KeeperException, don't attempt to notify other members</span> |
| <span class="source-line-no">106</span><span id="line-106"> if (ee.getCause() instanceof KeeperException) {</span> |
| <span class="source-line-no">107</span><span id="line-107"> LOG.debug("Was KeeperException, not redispatching error", ee);</span> |
| <span class="source-line-no">108</span><span id="line-108"> return;</span> |
| <span class="source-line-no">109</span><span id="line-109"> }</span> |
| <span class="source-line-no">110</span><span id="line-110"> // if it is other local error, then send it to the coordinator</span> |
| <span class="source-line-no">111</span><span id="line-111"> try {</span> |
| <span class="source-line-no">112</span><span id="line-112"> rpcs.sendMemberAborted(Subprocedure.this, ee);</span> |
| <span class="source-line-no">113</span><span id="line-113"> } catch (IOException e) {</span> |
| <span class="source-line-no">114</span><span id="line-114"> // this will fail all the running procedures, since the connection is down</span> |
| <span class="source-line-no">115</span><span id="line-115"> LOG.error("Can't reach controller, not propagating error", e);</span> |
| <span class="source-line-no">116</span><span id="line-116"> }</span> |
| <span class="source-line-no">117</span><span id="line-117"> }</span> |
| <span class="source-line-no">118</span><span id="line-118"> });</span> |
| <span class="source-line-no">119</span><span id="line-119"></span> |
| <span class="source-line-no">120</span><span id="line-120"> this.wakeFrequency = wakeFrequency;</span> |
| <span class="source-line-no">121</span><span id="line-121"> this.inGlobalBarrier = new CountDownLatch(1);</span> |
| <span class="source-line-no">122</span><span id="line-122"> this.releasedLocalBarrier = new CountDownLatch(1);</span> |
| <span class="source-line-no">123</span><span id="line-123"></span> |
| <span class="source-line-no">124</span><span id="line-124"> // accept error from timer thread, this needs to be started.</span> |
| <span class="source-line-no">125</span><span id="line-125"> this.executionTimeoutTimer = new TimeoutExceptionInjector(monitor, timeout);</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"> public String getName() {</span> |
| <span class="source-line-no">129</span><span id="line-129"> return barrierName;</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"> public String getMemberName() {</span> |
| <span class="source-line-no">133</span><span id="line-133"> return rpcs.getMemberName();</span> |
| <span class="source-line-no">134</span><span id="line-134"> }</span> |
| <span class="source-line-no">135</span><span id="line-135"></span> |
| <span class="source-line-no">136</span><span id="line-136"> private void rethrowException() throws ForeignException {</span> |
| <span class="source-line-no">137</span><span id="line-137"> monitor.rethrowException();</span> |
| <span class="source-line-no">138</span><span id="line-138"> }</span> |
| <span class="source-line-no">139</span><span id="line-139"></span> |
| <span class="source-line-no">140</span><span id="line-140"> /**</span> |
| <span class="source-line-no">141</span><span id="line-141"> * Execute the Subprocedure {@link #acquireBarrier()} and {@link #insideBarrier()} methods while</span> |
| <span class="source-line-no">142</span><span id="line-142"> * keeping some state for other threads to access. This would normally be executed by the</span> |
| <span class="source-line-no">143</span><span id="line-143"> * ProcedureMember when a acquire message comes from the coordinator. Rpcs are used to spend</span> |
| <span class="source-line-no">144</span><span id="line-144"> * message back to the coordinator after different phases are executed. Any exceptions caught</span> |
| <span class="source-line-no">145</span><span id="line-145"> * during the execution (except for InterruptedException) get converted and propagated to</span> |
| <span class="source-line-no">146</span><span id="line-146"> * coordinator via {@link ProcedureMemberRpcs#sendMemberAborted( Subprocedure, ForeignException)}.</span> |
| <span class="source-line-no">147</span><span id="line-147"> */</span> |
| <span class="source-line-no">148</span><span id="line-148"> @SuppressWarnings("finally")</span> |
| <span class="source-line-no">149</span><span id="line-149"> @Override</span> |
| <span class="source-line-no">150</span><span id="line-150"> final public Void call() {</span> |
| <span class="source-line-no">151</span><span id="line-151"> LOG.debug("Starting subprocedure '" + barrierName + "' with timeout "</span> |
| <span class="source-line-no">152</span><span id="line-152"> + executionTimeoutTimer.getMaxTime() + "ms");</span> |
| <span class="source-line-no">153</span><span id="line-153"> // start the execution timeout timer</span> |
| <span class="source-line-no">154</span><span id="line-154"> executionTimeoutTimer.start();</span> |
| <span class="source-line-no">155</span><span id="line-155"></span> |
| <span class="source-line-no">156</span><span id="line-156"> try {</span> |
| <span class="source-line-no">157</span><span id="line-157"> // start by checking for error first</span> |
| <span class="source-line-no">158</span><span id="line-158"> rethrowException();</span> |
| <span class="source-line-no">159</span><span id="line-159"> LOG.debug("Subprocedure '" + barrierName + "' starting 'acquire' stage");</span> |
| <span class="source-line-no">160</span><span id="line-160"> acquireBarrier();</span> |
| <span class="source-line-no">161</span><span id="line-161"> LOG.debug("Subprocedure '" + barrierName + "' locally acquired");</span> |
| <span class="source-line-no">162</span><span id="line-162"> rethrowException();</span> |
| <span class="source-line-no">163</span><span id="line-163"></span> |
| <span class="source-line-no">164</span><span id="line-164"> // vote yes to coordinator about being prepared</span> |
| <span class="source-line-no">165</span><span id="line-165"> rpcs.sendMemberAcquired(this);</span> |
| <span class="source-line-no">166</span><span id="line-166"> LOG.debug("Subprocedure '" + barrierName + "' coordinator notified of 'acquire', waiting on"</span> |
| <span class="source-line-no">167</span><span id="line-167"> + " 'reached' or 'abort' from coordinator");</span> |
| <span class="source-line-no">168</span><span id="line-168"></span> |
| <span class="source-line-no">169</span><span id="line-169"> // wait for the procedure to reach global barrier before proceding</span> |
| <span class="source-line-no">170</span><span id="line-170"> waitForReachedGlobalBarrier();</span> |
| <span class="source-line-no">171</span><span id="line-171"> rethrowException(); // if Coordinator aborts, will bail from here with exception</span> |
| <span class="source-line-no">172</span><span id="line-172"></span> |
| <span class="source-line-no">173</span><span id="line-173"> // In traditional 2PC, if a member reaches this state the TX has been committed and the</span> |
| <span class="source-line-no">174</span><span id="line-174"> // member is responsible for rolling forward and recovering and completing the subsequent</span> |
| <span class="source-line-no">175</span><span id="line-175"> // operations in the case of failure. It cannot rollback.</span> |
| <span class="source-line-no">176</span><span id="line-176"> //</span> |
| <span class="source-line-no">177</span><span id="line-177"> // This implementation is not 2PC since it can still rollback here, and thus has different</span> |
| <span class="source-line-no">178</span><span id="line-178"> // semantics.</span> |
| <span class="source-line-no">179</span><span id="line-179"></span> |
| <span class="source-line-no">180</span><span id="line-180"> LOG.debug("Subprocedure '" + barrierName + "' received 'reached' from coordinator.");</span> |
| <span class="source-line-no">181</span><span id="line-181"> byte[] dataToCoordinator = insideBarrier();</span> |
| <span class="source-line-no">182</span><span id="line-182"> LOG.debug("Subprocedure '" + barrierName + "' locally completed");</span> |
| <span class="source-line-no">183</span><span id="line-183"> rethrowException();</span> |
| <span class="source-line-no">184</span><span id="line-184"></span> |
| <span class="source-line-no">185</span><span id="line-185"> // Ack that the member has executed and released local barrier</span> |
| <span class="source-line-no">186</span><span id="line-186"> rpcs.sendMemberCompleted(this, dataToCoordinator);</span> |
| <span class="source-line-no">187</span><span id="line-187"> LOG.debug("Subprocedure '" + barrierName + "' has notified controller of completion");</span> |
| <span class="source-line-no">188</span><span id="line-188"></span> |
| <span class="source-line-no">189</span><span id="line-189"> // make sure we didn't get an external exception</span> |
| <span class="source-line-no">190</span><span id="line-190"> rethrowException();</span> |
| <span class="source-line-no">191</span><span id="line-191"> } catch (Exception e) {</span> |
| <span class="source-line-no">192</span><span id="line-192"> String msg = null;</span> |
| <span class="source-line-no">193</span><span id="line-193"> if (e instanceof InterruptedException) {</span> |
| <span class="source-line-no">194</span><span id="line-194"> msg = "Procedure '" + barrierName + "' aborting due to interrupt!"</span> |
| <span class="source-line-no">195</span><span id="line-195"> + " Likely due to pool shutdown.";</span> |
| <span class="source-line-no">196</span><span id="line-196"> Thread.currentThread().interrupt();</span> |
| <span class="source-line-no">197</span><span id="line-197"> } else if (e instanceof ForeignException) {</span> |
| <span class="source-line-no">198</span><span id="line-198"> msg = "Subprocedure '" + barrierName + "' aborting due to a ForeignException!";</span> |
| <span class="source-line-no">199</span><span id="line-199"> } else {</span> |
| <span class="source-line-no">200</span><span id="line-200"> msg = "Subprocedure '" + barrierName + "' failed!";</span> |
| <span class="source-line-no">201</span><span id="line-201"> }</span> |
| <span class="source-line-no">202</span><span id="line-202"> cancel(msg, e);</span> |
| <span class="source-line-no">203</span><span id="line-203"></span> |
| <span class="source-line-no">204</span><span id="line-204"> LOG.debug("Subprocedure '" + barrierName + "' running cleanup.");</span> |
| <span class="source-line-no">205</span><span id="line-205"> cleanup(e);</span> |
| <span class="source-line-no">206</span><span id="line-206"> } finally {</span> |
| <span class="source-line-no">207</span><span id="line-207"> releasedLocalBarrier.countDown();</span> |
| <span class="source-line-no">208</span><span id="line-208"></span> |
| <span class="source-line-no">209</span><span id="line-209"> // tell the timer we are done, if we get here successfully</span> |
| <span class="source-line-no">210</span><span id="line-210"> executionTimeoutTimer.complete();</span> |
| <span class="source-line-no">211</span><span id="line-211"> complete = true;</span> |
| <span class="source-line-no">212</span><span id="line-212"> LOG.debug("Subprocedure '" + barrierName + "' completed.");</span> |
| <span class="source-line-no">213</span><span id="line-213"> return null;</span> |
| <span class="source-line-no">214</span><span id="line-214"> }</span> |
| <span class="source-line-no">215</span><span id="line-215"> }</span> |
| <span class="source-line-no">216</span><span id="line-216"></span> |
| <span class="source-line-no">217</span><span id="line-217"> boolean isComplete() {</span> |
| <span class="source-line-no">218</span><span id="line-218"> return complete;</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"> /**</span> |
| <span class="source-line-no">222</span><span id="line-222"> * exposed for testing.</span> |
| <span class="source-line-no">223</span><span id="line-223"> */</span> |
| <span class="source-line-no">224</span><span id="line-224"> ForeignExceptionSnare getErrorCheckable() {</span> |
| <span class="source-line-no">225</span><span id="line-225"> return this.monitor;</span> |
| <span class="source-line-no">226</span><span id="line-226"> }</span> |
| <span class="source-line-no">227</span><span id="line-227"></span> |
| <span class="source-line-no">228</span><span id="line-228"> /**</span> |
| <span class="source-line-no">229</span><span id="line-229"> * The implementation of this method should gather and hold required resources (locks, disk space,</span> |
| <span class="source-line-no">230</span><span id="line-230"> * etc) to satisfy the Procedures barrier condition. For example, this would be where to make all</span> |
| <span class="source-line-no">231</span><span id="line-231"> * the regions on a RS on the quiescent for an procedure that required all regions to be globally</span> |
| <span class="source-line-no">232</span><span id="line-232"> * quiesed. Users should override this method. If a quiescent is not required, this is overkill</span> |
| <span class="source-line-no">233</span><span id="line-233"> * but can still be used to execute a procedure on all members and to propagate any exceptions.</span> |
| <span class="source-line-no">234</span><span id="line-234"> */</span> |
| <span class="source-line-no">235</span><span id="line-235"> abstract public void acquireBarrier() throws ForeignException;</span> |
| <span class="source-line-no">236</span><span id="line-236"></span> |
| <span class="source-line-no">237</span><span id="line-237"> /**</span> |
| <span class="source-line-no">238</span><span id="line-238"> * The implementation of this method should act with the assumption that the barrier condition has</span> |
| <span class="source-line-no">239</span><span id="line-239"> * been satisfied. Continuing the previous example, a condition could be that all RS's globally</span> |
| <span class="source-line-no">240</span><span id="line-240"> * have been quiesced, and procedures that require this precondition could be implemented here.</span> |
| <span class="source-line-no">241</span><span id="line-241"> * The implementation should also collect the result of the subprocedure as data to be returned to</span> |
| <span class="source-line-no">242</span><span id="line-242"> * the coordinator upon successful completion. Users should override this method.</span> |
| <span class="source-line-no">243</span><span id="line-243"> * @return the data the subprocedure wants to return to coordinator side.</span> |
| <span class="source-line-no">244</span><span id="line-244"> */</span> |
| <span class="source-line-no">245</span><span id="line-245"> abstract public byte[] insideBarrier() throws ForeignException;</span> |
| <span class="source-line-no">246</span><span id="line-246"></span> |
| <span class="source-line-no">247</span><span id="line-247"> /**</span> |
| <span class="source-line-no">248</span><span id="line-248"> * Users should override this method. This implementation of this method should rollback and</span> |
| <span class="source-line-no">249</span><span id="line-249"> * cleanup any temporary or partially completed state that the {@link #acquireBarrier()} may have</span> |
| <span class="source-line-no">250</span><span id="line-250"> * created.</span> |
| <span class="source-line-no">251</span><span id="line-251"> */</span> |
| <span class="source-line-no">252</span><span id="line-252"> abstract public void cleanup(Exception e);</span> |
| <span class="source-line-no">253</span><span id="line-253"></span> |
| <span class="source-line-no">254</span><span id="line-254"> /**</span> |
| <span class="source-line-no">255</span><span id="line-255"> * Method to cancel the Subprocedure by injecting an exception from and external source.</span> |
| <span class="source-line-no">256</span><span id="line-256"> */</span> |
| <span class="source-line-no">257</span><span id="line-257"> public void cancel(String msg, Throwable cause) {</span> |
| <span class="source-line-no">258</span><span id="line-258"> LOG.error(msg, cause);</span> |
| <span class="source-line-no">259</span><span id="line-259"> complete = true;</span> |
| <span class="source-line-no">260</span><span id="line-260"> if (cause instanceof ForeignException) {</span> |
| <span class="source-line-no">261</span><span id="line-261"> monitor.receive((ForeignException) cause);</span> |
| <span class="source-line-no">262</span><span id="line-262"> } else {</span> |
| <span class="source-line-no">263</span><span id="line-263"> monitor.receive(new ForeignException(getMemberName(), cause));</span> |
| <span class="source-line-no">264</span><span id="line-264"> }</span> |
| <span class="source-line-no">265</span><span id="line-265"> }</span> |
| <span class="source-line-no">266</span><span id="line-266"></span> |
| <span class="source-line-no">267</span><span id="line-267"> /**</span> |
| <span class="source-line-no">268</span><span id="line-268"> * Callback for the member rpcs to call when the global barrier has been reached. This unblocks</span> |
| <span class="source-line-no">269</span><span id="line-269"> * the main subprocedure exectuion thread so that the Subprocedure's {@link #insideBarrier()}</span> |
| <span class="source-line-no">270</span><span id="line-270"> * method can be run.</span> |
| <span class="source-line-no">271</span><span id="line-271"> */</span> |
| <span class="source-line-no">272</span><span id="line-272"> public void receiveReachedGlobalBarrier() {</span> |
| <span class="source-line-no">273</span><span id="line-273"> inGlobalBarrier.countDown();</span> |
| <span class="source-line-no">274</span><span id="line-274"> }</span> |
| <span class="source-line-no">275</span><span id="line-275"></span> |
| <span class="source-line-no">276</span><span id="line-276"> //</span> |
| <span class="source-line-no">277</span><span id="line-277"> // Subprocedure Internal State interface</span> |
| <span class="source-line-no">278</span><span id="line-278"> //</span> |
| <span class="source-line-no">279</span><span id="line-279"></span> |
| <span class="source-line-no">280</span><span id="line-280"> /**</span> |
| <span class="source-line-no">281</span><span id="line-281"> * Wait for the reached global barrier notification. Package visibility for testing</span> |
| <span class="source-line-no">282</span><span id="line-282"> */</span> |
| <span class="source-line-no">283</span><span id="line-283"> void waitForReachedGlobalBarrier() throws ForeignException, InterruptedException {</span> |
| <span class="source-line-no">284</span><span id="line-284"> Procedure.waitForLatch(inGlobalBarrier, monitor, wakeFrequency,</span> |
| <span class="source-line-no">285</span><span id="line-285"> barrierName + ":remote acquired");</span> |
| <span class="source-line-no">286</span><span id="line-286"> }</span> |
| <span class="source-line-no">287</span><span id="line-287"></span> |
| <span class="source-line-no">288</span><span id="line-288"> /**</span> |
| <span class="source-line-no">289</span><span id="line-289"> * Waits until the entire procedure has globally completed, or has been aborted.</span> |
| <span class="source-line-no">290</span><span id="line-290"> */</span> |
| <span class="source-line-no">291</span><span id="line-291"> public void waitForLocallyCompleted() throws ForeignException, InterruptedException {</span> |
| <span class="source-line-no">292</span><span id="line-292"> Procedure.waitForLatch(releasedLocalBarrier, monitor, wakeFrequency,</span> |
| <span class="source-line-no">293</span><span id="line-293"> barrierName + ":completed");</span> |
| <span class="source-line-no">294</span><span id="line-294"> }</span> |
| <span class="source-line-no">295</span><span id="line-295"></span> |
| <span class="source-line-no">296</span><span id="line-296"> /**</span> |
| <span class="source-line-no">297</span><span id="line-297"> * Empty Subprocedure for testing. Must be public for stubbing used in testing to work.</span> |
| <span class="source-line-no">298</span><span id="line-298"> */</span> |
| <span class="source-line-no">299</span><span id="line-299"> public static class SubprocedureImpl extends Subprocedure {</span> |
| <span class="source-line-no">300</span><span id="line-300"></span> |
| <span class="source-line-no">301</span><span id="line-301"> public SubprocedureImpl(ProcedureMember member, String opName,</span> |
| <span class="source-line-no">302</span><span id="line-302"> ForeignExceptionDispatcher monitor, long wakeFrequency, long timeout) {</span> |
| <span class="source-line-no">303</span><span id="line-303"> super(member, opName, monitor, wakeFrequency, timeout);</span> |
| <span class="source-line-no">304</span><span id="line-304"> }</span> |
| <span class="source-line-no">305</span><span id="line-305"></span> |
| <span class="source-line-no">306</span><span id="line-306"> @Override</span> |
| <span class="source-line-no">307</span><span id="line-307"> public void acquireBarrier() throws ForeignException {</span> |
| <span class="source-line-no">308</span><span id="line-308"> }</span> |
| <span class="source-line-no">309</span><span id="line-309"></span> |
| <span class="source-line-no">310</span><span id="line-310"> @Override</span> |
| <span class="source-line-no">311</span><span id="line-311"> public byte[] insideBarrier() throws ForeignException {</span> |
| <span class="source-line-no">312</span><span id="line-312"> return new byte[0];</span> |
| <span class="source-line-no">313</span><span id="line-313"> }</span> |
| <span class="source-line-no">314</span><span id="line-314"></span> |
| <span class="source-line-no">315</span><span id="line-315"> @Override</span> |
| <span class="source-line-no">316</span><span id="line-316"> public void cleanup(Exception e) {</span> |
| <span class="source-line-no">317</span><span id="line-317"> }</span> |
| <span class="source-line-no">318</span><span id="line-318"> }</span> |
| <span class="source-line-no">319</span><span id="line-319">}</span> |
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| </pre> |
| </div> |
| </main> |
| </body> |
| </html> |
