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<pre><span class="sourceLineNo">001</span>/**<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<span class="sourceLineNo">003</span> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a>
<span class="sourceLineNo">004</span> * distributed with this work for additional information<a name="line.4"></a>
<span class="sourceLineNo">005</span> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a>
<span class="sourceLineNo">006</span> * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
<span class="sourceLineNo">007</span> * "License"); you may not use this file except in compliance<a name="line.7"></a>
<span class="sourceLineNo">008</span> * with the License. You may obtain a copy of the License at<a name="line.8"></a>
<span class="sourceLineNo">009</span> *<a name="line.9"></a>
<span class="sourceLineNo">010</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<span class="sourceLineNo">011</span> *<a name="line.11"></a>
<span class="sourceLineNo">012</span> * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
<span class="sourceLineNo">013</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
<span class="sourceLineNo">014</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
<span class="sourceLineNo">015</span> * See the License for the specific language governing permissions and<a name="line.15"></a>
<span class="sourceLineNo">016</span> * limitations under the License.<a name="line.16"></a>
<span class="sourceLineNo">017</span> */<a name="line.17"></a>
<span class="sourceLineNo">018</span>package org.apache.hadoop.hbase.procedure2;<a name="line.18"></a>
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>import java.io.IOException;<a name="line.20"></a>
<span class="sourceLineNo">021</span>import java.util.ArrayList;<a name="line.21"></a>
<span class="sourceLineNo">022</span>import java.util.Arrays;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import java.util.List;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import java.util.concurrent.atomic.AtomicBoolean;<a name="line.24"></a>
<span class="sourceLineNo">025</span><a name="line.25"></a>
<span class="sourceLineNo">026</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import org.apache.yetus.audience.InterfaceStability;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import org.slf4j.Logger;<a name="line.28"></a>
<span class="sourceLineNo">029</span>import org.slf4j.LoggerFactory;<a name="line.29"></a>
<span class="sourceLineNo">030</span><a name="line.30"></a>
<span class="sourceLineNo">031</span>import org.apache.hbase.thirdparty.com.google.common.annotations.VisibleForTesting;<a name="line.31"></a>
<span class="sourceLineNo">032</span><a name="line.32"></a>
<span class="sourceLineNo">033</span>import org.apache.hadoop.hbase.shaded.protobuf.generated.ProcedureProtos.StateMachineProcedureData;<a name="line.33"></a>
<span class="sourceLineNo">034</span><a name="line.34"></a>
<span class="sourceLineNo">035</span>/**<a name="line.35"></a>
<span class="sourceLineNo">036</span> * Procedure described by a series of steps.<a name="line.36"></a>
<span class="sourceLineNo">037</span> *<a name="line.37"></a>
<span class="sourceLineNo">038</span> * &lt;p&gt;The procedure implementor must have an enum of 'states', describing<a name="line.38"></a>
<span class="sourceLineNo">039</span> * the various step of the procedure.<a name="line.39"></a>
<span class="sourceLineNo">040</span> * Once the procedure is running, the procedure-framework will call executeFromState()<a name="line.40"></a>
<span class="sourceLineNo">041</span> * using the 'state' provided by the user. The first call to executeFromState()<a name="line.41"></a>
<span class="sourceLineNo">042</span> * will be performed with 'state = null'. The implementor can jump between<a name="line.42"></a>
<span class="sourceLineNo">043</span> * states using setNextState(MyStateEnum.ordinal()).<a name="line.43"></a>
<span class="sourceLineNo">044</span> * The rollback will call rollbackState() for each state that was executed, in reverse order.<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>@InterfaceStability.Evolving<a name="line.47"></a>
<span class="sourceLineNo">048</span>public abstract class StateMachineProcedure&lt;TEnvironment, TState&gt;<a name="line.48"></a>
<span class="sourceLineNo">049</span> extends Procedure&lt;TEnvironment&gt; {<a name="line.49"></a>
<span class="sourceLineNo">050</span> private static final Logger LOG = LoggerFactory.getLogger(StateMachineProcedure.class);<a name="line.50"></a>
<span class="sourceLineNo">051</span><a name="line.51"></a>
<span class="sourceLineNo">052</span> private static final int EOF_STATE = Integer.MIN_VALUE;<a name="line.52"></a>
<span class="sourceLineNo">053</span><a name="line.53"></a>
<span class="sourceLineNo">054</span> private final AtomicBoolean aborted = new AtomicBoolean(false);<a name="line.54"></a>
<span class="sourceLineNo">055</span><a name="line.55"></a>
<span class="sourceLineNo">056</span> private Flow stateFlow = Flow.HAS_MORE_STATE;<a name="line.56"></a>
<span class="sourceLineNo">057</span> protected int stateCount = 0;<a name="line.57"></a>
<span class="sourceLineNo">058</span> private int[] states = null;<a name="line.58"></a>
<span class="sourceLineNo">059</span><a name="line.59"></a>
<span class="sourceLineNo">060</span> private List&lt;Procedure&lt;TEnvironment&gt;&gt; subProcList = null;<a name="line.60"></a>
<span class="sourceLineNo">061</span><a name="line.61"></a>
<span class="sourceLineNo">062</span> protected final int getCycles() {<a name="line.62"></a>
<span class="sourceLineNo">063</span> return cycles;<a name="line.63"></a>
<span class="sourceLineNo">064</span> }<a name="line.64"></a>
<span class="sourceLineNo">065</span><a name="line.65"></a>
<span class="sourceLineNo">066</span> /**<a name="line.66"></a>
<span class="sourceLineNo">067</span> * Cycles on same state. Good for figuring if we are stuck.<a name="line.67"></a>
<span class="sourceLineNo">068</span> */<a name="line.68"></a>
<span class="sourceLineNo">069</span> private int cycles = 0;<a name="line.69"></a>
<span class="sourceLineNo">070</span><a name="line.70"></a>
<span class="sourceLineNo">071</span> /**<a name="line.71"></a>
<span class="sourceLineNo">072</span> * Ordinal of the previous state. So we can tell if we are progressing or not.<a name="line.72"></a>
<span class="sourceLineNo">073</span> */<a name="line.73"></a>
<span class="sourceLineNo">074</span> private int previousState;<a name="line.74"></a>
<span class="sourceLineNo">075</span><a name="line.75"></a>
<span class="sourceLineNo">076</span> @VisibleForTesting<a name="line.76"></a>
<span class="sourceLineNo">077</span> public enum Flow {<a name="line.77"></a>
<span class="sourceLineNo">078</span> HAS_MORE_STATE,<a name="line.78"></a>
<span class="sourceLineNo">079</span> NO_MORE_STATE,<a name="line.79"></a>
<span class="sourceLineNo">080</span> }<a name="line.80"></a>
<span class="sourceLineNo">081</span><a name="line.81"></a>
<span class="sourceLineNo">082</span> /**<a name="line.82"></a>
<span class="sourceLineNo">083</span> * called to perform a single step of the specified 'state' of the procedure<a name="line.83"></a>
<span class="sourceLineNo">084</span> * @param state state to execute<a name="line.84"></a>
<span class="sourceLineNo">085</span> * @return Flow.NO_MORE_STATE if the procedure is completed,<a name="line.85"></a>
<span class="sourceLineNo">086</span> * Flow.HAS_MORE_STATE if there is another step.<a name="line.86"></a>
<span class="sourceLineNo">087</span> */<a name="line.87"></a>
<span class="sourceLineNo">088</span> protected abstract Flow executeFromState(TEnvironment env, TState state)<a name="line.88"></a>
<span class="sourceLineNo">089</span> throws ProcedureSuspendedException, ProcedureYieldException, InterruptedException;<a name="line.89"></a>
<span class="sourceLineNo">090</span><a name="line.90"></a>
<span class="sourceLineNo">091</span> /**<a name="line.91"></a>
<span class="sourceLineNo">092</span> * called to perform the rollback of the specified state<a name="line.92"></a>
<span class="sourceLineNo">093</span> * @param state state to rollback<a name="line.93"></a>
<span class="sourceLineNo">094</span> * @throws IOException temporary failure, the rollback will retry later<a name="line.94"></a>
<span class="sourceLineNo">095</span> */<a name="line.95"></a>
<span class="sourceLineNo">096</span> protected abstract void rollbackState(TEnvironment env, TState state)<a name="line.96"></a>
<span class="sourceLineNo">097</span> throws IOException, InterruptedException;<a name="line.97"></a>
<span class="sourceLineNo">098</span><a name="line.98"></a>
<span class="sourceLineNo">099</span> /**<a name="line.99"></a>
<span class="sourceLineNo">100</span> * Convert an ordinal (or state id) to an Enum (or more descriptive) state object.<a name="line.100"></a>
<span class="sourceLineNo">101</span> * @param stateId the ordinal() of the state enum (or state id)<a name="line.101"></a>
<span class="sourceLineNo">102</span> * @return the state enum object<a name="line.102"></a>
<span class="sourceLineNo">103</span> */<a name="line.103"></a>
<span class="sourceLineNo">104</span> protected abstract TState getState(int stateId);<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> * Convert the Enum (or more descriptive) state object to an ordinal (or state id).<a name="line.107"></a>
<span class="sourceLineNo">108</span> * @param state the state enum object<a name="line.108"></a>
<span class="sourceLineNo">109</span> * @return stateId the ordinal() of the state enum (or state id)<a name="line.109"></a>
<span class="sourceLineNo">110</span> */<a name="line.110"></a>
<span class="sourceLineNo">111</span> protected abstract int getStateId(TState state);<a name="line.111"></a>
<span class="sourceLineNo">112</span><a name="line.112"></a>
<span class="sourceLineNo">113</span> /**<a name="line.113"></a>
<span class="sourceLineNo">114</span> * Return the initial state object that will be used for the first call to executeFromState().<a name="line.114"></a>
<span class="sourceLineNo">115</span> * @return the initial state enum object<a name="line.115"></a>
<span class="sourceLineNo">116</span> */<a name="line.116"></a>
<span class="sourceLineNo">117</span> protected abstract TState getInitialState();<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> * Set the next state for the procedure.<a name="line.120"></a>
<span class="sourceLineNo">121</span> * @param state the state enum object<a name="line.121"></a>
<span class="sourceLineNo">122</span> */<a name="line.122"></a>
<span class="sourceLineNo">123</span> protected void setNextState(final TState state) {<a name="line.123"></a>
<span class="sourceLineNo">124</span> setNextState(getStateId(state));<a name="line.124"></a>
<span class="sourceLineNo">125</span> failIfAborted();<a name="line.125"></a>
<span class="sourceLineNo">126</span> }<a name="line.126"></a>
<span class="sourceLineNo">127</span><a name="line.127"></a>
<span class="sourceLineNo">128</span> /**<a name="line.128"></a>
<span class="sourceLineNo">129</span> * By default, the executor will try ro run all the steps of the procedure start to finish.<a name="line.129"></a>
<span class="sourceLineNo">130</span> * Return true to make the executor yield between execution steps to<a name="line.130"></a>
<span class="sourceLineNo">131</span> * give other procedures time to run their steps.<a name="line.131"></a>
<span class="sourceLineNo">132</span> * @param state the state we are going to execute next.<a name="line.132"></a>
<span class="sourceLineNo">133</span> * @return Return true if the executor should yield before the execution of the specified step.<a name="line.133"></a>
<span class="sourceLineNo">134</span> * Defaults to return false.<a name="line.134"></a>
<span class="sourceLineNo">135</span> */<a name="line.135"></a>
<span class="sourceLineNo">136</span> protected boolean isYieldBeforeExecuteFromState(TEnvironment env, TState state) {<a name="line.136"></a>
<span class="sourceLineNo">137</span> return false;<a name="line.137"></a>
<span class="sourceLineNo">138</span> }<a name="line.138"></a>
<span class="sourceLineNo">139</span><a name="line.139"></a>
<span class="sourceLineNo">140</span> /**<a name="line.140"></a>
<span class="sourceLineNo">141</span> * Add a child procedure to execute<a name="line.141"></a>
<span class="sourceLineNo">142</span> * @param subProcedure the child procedure<a name="line.142"></a>
<span class="sourceLineNo">143</span> */<a name="line.143"></a>
<span class="sourceLineNo">144</span> protected &lt;T extends Procedure&lt;TEnvironment&gt;&gt; void addChildProcedure(<a name="line.144"></a>
<span class="sourceLineNo">145</span> @SuppressWarnings("unchecked") T... subProcedure) {<a name="line.145"></a>
<span class="sourceLineNo">146</span> if (subProcedure == null) {<a name="line.146"></a>
<span class="sourceLineNo">147</span> return;<a name="line.147"></a>
<span class="sourceLineNo">148</span> }<a name="line.148"></a>
<span class="sourceLineNo">149</span> final int len = subProcedure.length;<a name="line.149"></a>
<span class="sourceLineNo">150</span> if (len == 0) {<a name="line.150"></a>
<span class="sourceLineNo">151</span> return;<a name="line.151"></a>
<span class="sourceLineNo">152</span> }<a name="line.152"></a>
<span class="sourceLineNo">153</span> if (subProcList == null) {<a name="line.153"></a>
<span class="sourceLineNo">154</span> subProcList = new ArrayList&lt;&gt;(len);<a name="line.154"></a>
<span class="sourceLineNo">155</span> }<a name="line.155"></a>
<span class="sourceLineNo">156</span> for (int i = 0; i &lt; len; ++i) {<a name="line.156"></a>
<span class="sourceLineNo">157</span> Procedure&lt;TEnvironment&gt; proc = subProcedure[i];<a name="line.157"></a>
<span class="sourceLineNo">158</span> if (!proc.hasOwner()) {<a name="line.158"></a>
<span class="sourceLineNo">159</span> proc.setOwner(getOwner());<a name="line.159"></a>
<span class="sourceLineNo">160</span> }<a name="line.160"></a>
<span class="sourceLineNo">161</span><a name="line.161"></a>
<span class="sourceLineNo">162</span> subProcList.add(proc);<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> protected Procedure[] execute(final TEnvironment env)<a name="line.167"></a>
<span class="sourceLineNo">168</span> throws ProcedureSuspendedException, ProcedureYieldException, InterruptedException {<a name="line.168"></a>
<span class="sourceLineNo">169</span> updateTimestamp();<a name="line.169"></a>
<span class="sourceLineNo">170</span> try {<a name="line.170"></a>
<span class="sourceLineNo">171</span> failIfAborted();<a name="line.171"></a>
<span class="sourceLineNo">172</span><a name="line.172"></a>
<span class="sourceLineNo">173</span> if (!hasMoreState() || isFailed()) {<a name="line.173"></a>
<span class="sourceLineNo">174</span> return null;<a name="line.174"></a>
<span class="sourceLineNo">175</span> }<a name="line.175"></a>
<span class="sourceLineNo">176</span><a name="line.176"></a>
<span class="sourceLineNo">177</span> TState state = getCurrentState();<a name="line.177"></a>
<span class="sourceLineNo">178</span> if (stateCount == 0) {<a name="line.178"></a>
<span class="sourceLineNo">179</span> setNextState(getStateId(state));<a name="line.179"></a>
<span class="sourceLineNo">180</span> }<a name="line.180"></a>
<span class="sourceLineNo">181</span><a name="line.181"></a>
<span class="sourceLineNo">182</span> if (LOG.isTraceEnabled()) {<a name="line.182"></a>
<span class="sourceLineNo">183</span> LOG.trace(state + " " + this + "; cycles=" + this.cycles);<a name="line.183"></a>
<span class="sourceLineNo">184</span> }<a name="line.184"></a>
<span class="sourceLineNo">185</span> // Keep running count of cycles<a name="line.185"></a>
<span class="sourceLineNo">186</span> if (getStateId(state) != this.previousState) {<a name="line.186"></a>
<span class="sourceLineNo">187</span> this.previousState = getStateId(state);<a name="line.187"></a>
<span class="sourceLineNo">188</span> this.cycles = 0;<a name="line.188"></a>
<span class="sourceLineNo">189</span> } else {<a name="line.189"></a>
<span class="sourceLineNo">190</span> this.cycles++;<a name="line.190"></a>
<span class="sourceLineNo">191</span> }<a name="line.191"></a>
<span class="sourceLineNo">192</span><a name="line.192"></a>
<span class="sourceLineNo">193</span> LOG.trace("{}", this);<a name="line.193"></a>
<span class="sourceLineNo">194</span> stateFlow = executeFromState(env, state);<a name="line.194"></a>
<span class="sourceLineNo">195</span> if (!hasMoreState()) {<a name="line.195"></a>
<span class="sourceLineNo">196</span> setNextState(EOF_STATE);<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> if (subProcList != null &amp;&amp; !subProcList.isEmpty()) {<a name="line.199"></a>
<span class="sourceLineNo">200</span> Procedure[] subProcedures = subProcList.toArray(new Procedure[subProcList.size()]);<a name="line.200"></a>
<span class="sourceLineNo">201</span> subProcList = null;<a name="line.201"></a>
<span class="sourceLineNo">202</span> return subProcedures;<a name="line.202"></a>
<span class="sourceLineNo">203</span> }<a name="line.203"></a>
<span class="sourceLineNo">204</span> return (isWaiting() || isFailed() || !hasMoreState()) ? null : new Procedure[] {this};<a name="line.204"></a>
<span class="sourceLineNo">205</span> } finally {<a name="line.205"></a>
<span class="sourceLineNo">206</span> updateTimestamp();<a name="line.206"></a>
<span class="sourceLineNo">207</span> }<a name="line.207"></a>
<span class="sourceLineNo">208</span> }<a name="line.208"></a>
<span class="sourceLineNo">209</span><a name="line.209"></a>
<span class="sourceLineNo">210</span> @Override<a name="line.210"></a>
<span class="sourceLineNo">211</span> protected void rollback(final TEnvironment env)<a name="line.211"></a>
<span class="sourceLineNo">212</span> throws IOException, InterruptedException {<a name="line.212"></a>
<span class="sourceLineNo">213</span> if (isEofState()) {<a name="line.213"></a>
<span class="sourceLineNo">214</span> stateCount--;<a name="line.214"></a>
<span class="sourceLineNo">215</span> }<a name="line.215"></a>
<span class="sourceLineNo">216</span><a name="line.216"></a>
<span class="sourceLineNo">217</span> try {<a name="line.217"></a>
<span class="sourceLineNo">218</span> updateTimestamp();<a name="line.218"></a>
<span class="sourceLineNo">219</span> rollbackState(env, getCurrentState());<a name="line.219"></a>
<span class="sourceLineNo">220</span> } finally {<a name="line.220"></a>
<span class="sourceLineNo">221</span> stateCount--;<a name="line.221"></a>
<span class="sourceLineNo">222</span> updateTimestamp();<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><a name="line.225"></a>
<span class="sourceLineNo">226</span> protected boolean isEofState() {<a name="line.226"></a>
<span class="sourceLineNo">227</span> return stateCount &gt; 0 &amp;&amp; states[stateCount-1] == EOF_STATE;<a name="line.227"></a>
<span class="sourceLineNo">228</span> }<a name="line.228"></a>
<span class="sourceLineNo">229</span><a name="line.229"></a>
<span class="sourceLineNo">230</span> @Override<a name="line.230"></a>
<span class="sourceLineNo">231</span> protected boolean abort(final TEnvironment env) {<a name="line.231"></a>
<span class="sourceLineNo">232</span> LOG.debug("Abort requested for {}", this);<a name="line.232"></a>
<span class="sourceLineNo">233</span> if (!hasMoreState()) {<a name="line.233"></a>
<span class="sourceLineNo">234</span> LOG.warn("Ignore abort request on {} because it has already been finished", this);<a name="line.234"></a>
<span class="sourceLineNo">235</span> return false;<a name="line.235"></a>
<span class="sourceLineNo">236</span> }<a name="line.236"></a>
<span class="sourceLineNo">237</span> if (!isRollbackSupported(getCurrentState())) {<a name="line.237"></a>
<span class="sourceLineNo">238</span> LOG.warn("Ignore abort request on {} because it does not support rollback", this);<a name="line.238"></a>
<span class="sourceLineNo">239</span> return false;<a name="line.239"></a>
<span class="sourceLineNo">240</span> }<a name="line.240"></a>
<span class="sourceLineNo">241</span> aborted.set(true);<a name="line.241"></a>
<span class="sourceLineNo">242</span> return true;<a name="line.242"></a>
<span class="sourceLineNo">243</span> }<a name="line.243"></a>
<span class="sourceLineNo">244</span><a name="line.244"></a>
<span class="sourceLineNo">245</span> /**<a name="line.245"></a>
<span class="sourceLineNo">246</span> * If procedure has more states then abort it otherwise procedure is finished and abort can be<a name="line.246"></a>
<span class="sourceLineNo">247</span> * ignored.<a name="line.247"></a>
<span class="sourceLineNo">248</span> */<a name="line.248"></a>
<span class="sourceLineNo">249</span> protected final void failIfAborted() {<a name="line.249"></a>
<span class="sourceLineNo">250</span> if (aborted.get()) {<a name="line.250"></a>
<span class="sourceLineNo">251</span> if (hasMoreState()) {<a name="line.251"></a>
<span class="sourceLineNo">252</span> setAbortFailure(getClass().getSimpleName(), "abort requested");<a name="line.252"></a>
<span class="sourceLineNo">253</span> } else {<a name="line.253"></a>
<span class="sourceLineNo">254</span> LOG.warn("Ignoring abort request on state='" + getCurrentState() + "' for " + this);<a name="line.254"></a>
<span class="sourceLineNo">255</span> }<a name="line.255"></a>
<span class="sourceLineNo">256</span> }<a name="line.256"></a>
<span class="sourceLineNo">257</span> }<a name="line.257"></a>
<span class="sourceLineNo">258</span><a name="line.258"></a>
<span class="sourceLineNo">259</span> /**<a name="line.259"></a>
<span class="sourceLineNo">260</span> * Used by the default implementation of abort() to know if the current state can be aborted<a name="line.260"></a>
<span class="sourceLineNo">261</span> * and rollback can be triggered.<a name="line.261"></a>
<span class="sourceLineNo">262</span> */<a name="line.262"></a>
<span class="sourceLineNo">263</span> protected boolean isRollbackSupported(final TState state) {<a name="line.263"></a>
<span class="sourceLineNo">264</span> return false;<a name="line.264"></a>
<span class="sourceLineNo">265</span> }<a name="line.265"></a>
<span class="sourceLineNo">266</span><a name="line.266"></a>
<span class="sourceLineNo">267</span> @Override<a name="line.267"></a>
<span class="sourceLineNo">268</span> protected boolean isYieldAfterExecutionStep(final TEnvironment env) {<a name="line.268"></a>
<span class="sourceLineNo">269</span> return isYieldBeforeExecuteFromState(env, getCurrentState());<a name="line.269"></a>
<span class="sourceLineNo">270</span> }<a name="line.270"></a>
<span class="sourceLineNo">271</span><a name="line.271"></a>
<span class="sourceLineNo">272</span> private boolean hasMoreState() {<a name="line.272"></a>
<span class="sourceLineNo">273</span> return stateFlow != Flow.NO_MORE_STATE;<a name="line.273"></a>
<span class="sourceLineNo">274</span> }<a name="line.274"></a>
<span class="sourceLineNo">275</span><a name="line.275"></a>
<span class="sourceLineNo">276</span> protected TState getCurrentState() {<a name="line.276"></a>
<span class="sourceLineNo">277</span> return stateCount &gt; 0 ? getState(states[stateCount-1]) : getInitialState();<a name="line.277"></a>
<span class="sourceLineNo">278</span> }<a name="line.278"></a>
<span class="sourceLineNo">279</span><a name="line.279"></a>
<span class="sourceLineNo">280</span> /**<a name="line.280"></a>
<span class="sourceLineNo">281</span> * This method is used from test code as it cannot be assumed that state transition will happen<a name="line.281"></a>
<span class="sourceLineNo">282</span> * sequentially. Some procedures may skip steps/ states, some may add intermediate steps in<a name="line.282"></a>
<span class="sourceLineNo">283</span> * future.<a name="line.283"></a>
<span class="sourceLineNo">284</span> */<a name="line.284"></a>
<span class="sourceLineNo">285</span> @VisibleForTesting<a name="line.285"></a>
<span class="sourceLineNo">286</span> public int getCurrentStateId() {<a name="line.286"></a>
<span class="sourceLineNo">287</span> return getStateId(getCurrentState());<a name="line.287"></a>
<span class="sourceLineNo">288</span> }<a name="line.288"></a>
<span class="sourceLineNo">289</span><a name="line.289"></a>
<span class="sourceLineNo">290</span> /**<a name="line.290"></a>
<span class="sourceLineNo">291</span> * Set the next state for the procedure.<a name="line.291"></a>
<span class="sourceLineNo">292</span> * @param stateId the ordinal() of the state enum (or state id)<a name="line.292"></a>
<span class="sourceLineNo">293</span> */<a name="line.293"></a>
<span class="sourceLineNo">294</span> private void setNextState(final int stateId) {<a name="line.294"></a>
<span class="sourceLineNo">295</span> if (states == null || states.length == stateCount) {<a name="line.295"></a>
<span class="sourceLineNo">296</span> int newCapacity = stateCount + 8;<a name="line.296"></a>
<span class="sourceLineNo">297</span> if (states != null) {<a name="line.297"></a>
<span class="sourceLineNo">298</span> states = Arrays.copyOf(states, newCapacity);<a name="line.298"></a>
<span class="sourceLineNo">299</span> } else {<a name="line.299"></a>
<span class="sourceLineNo">300</span> states = new int[newCapacity];<a name="line.300"></a>
<span class="sourceLineNo">301</span> }<a name="line.301"></a>
<span class="sourceLineNo">302</span> }<a name="line.302"></a>
<span class="sourceLineNo">303</span> states[stateCount++] = stateId;<a name="line.303"></a>
<span class="sourceLineNo">304</span> }<a name="line.304"></a>
<span class="sourceLineNo">305</span><a name="line.305"></a>
<span class="sourceLineNo">306</span> @Override<a name="line.306"></a>
<span class="sourceLineNo">307</span> protected void toStringState(StringBuilder builder) {<a name="line.307"></a>
<span class="sourceLineNo">308</span> super.toStringState(builder);<a name="line.308"></a>
<span class="sourceLineNo">309</span> if (!isFinished() &amp;&amp; !isEofState() &amp;&amp; getCurrentState() != null) {<a name="line.309"></a>
<span class="sourceLineNo">310</span> builder.append(":").append(getCurrentState());<a name="line.310"></a>
<span class="sourceLineNo">311</span> }<a name="line.311"></a>
<span class="sourceLineNo">312</span> }<a name="line.312"></a>
<span class="sourceLineNo">313</span><a name="line.313"></a>
<span class="sourceLineNo">314</span> @Override<a name="line.314"></a>
<span class="sourceLineNo">315</span> protected void serializeStateData(ProcedureStateSerializer serializer)<a name="line.315"></a>
<span class="sourceLineNo">316</span> throws IOException {<a name="line.316"></a>
<span class="sourceLineNo">317</span> StateMachineProcedureData.Builder data = StateMachineProcedureData.newBuilder();<a name="line.317"></a>
<span class="sourceLineNo">318</span> for (int i = 0; i &lt; stateCount; ++i) {<a name="line.318"></a>
<span class="sourceLineNo">319</span> data.addState(states[i]);<a name="line.319"></a>
<span class="sourceLineNo">320</span> }<a name="line.320"></a>
<span class="sourceLineNo">321</span> serializer.serialize(data.build());<a name="line.321"></a>
<span class="sourceLineNo">322</span> }<a name="line.322"></a>
<span class="sourceLineNo">323</span><a name="line.323"></a>
<span class="sourceLineNo">324</span> @Override<a name="line.324"></a>
<span class="sourceLineNo">325</span> protected void deserializeStateData(ProcedureStateSerializer serializer)<a name="line.325"></a>
<span class="sourceLineNo">326</span> throws IOException {<a name="line.326"></a>
<span class="sourceLineNo">327</span> StateMachineProcedureData data = serializer.deserialize(StateMachineProcedureData.class);<a name="line.327"></a>
<span class="sourceLineNo">328</span> stateCount = data.getStateCount();<a name="line.328"></a>
<span class="sourceLineNo">329</span> if (stateCount &gt; 0) {<a name="line.329"></a>
<span class="sourceLineNo">330</span> states = new int[stateCount];<a name="line.330"></a>
<span class="sourceLineNo">331</span> for (int i = 0; i &lt; stateCount; ++i) {<a name="line.331"></a>
<span class="sourceLineNo">332</span> states[i] = data.getState(i);<a name="line.332"></a>
<span class="sourceLineNo">333</span> }<a name="line.333"></a>
<span class="sourceLineNo">334</span> if (isEofState()) {<a name="line.334"></a>
<span class="sourceLineNo">335</span> stateFlow = Flow.NO_MORE_STATE;<a name="line.335"></a>
<span class="sourceLineNo">336</span> }<a name="line.336"></a>
<span class="sourceLineNo">337</span> } else {<a name="line.337"></a>
<span class="sourceLineNo">338</span> states = null;<a name="line.338"></a>
<span class="sourceLineNo">339</span> }<a name="line.339"></a>
<span class="sourceLineNo">340</span> }<a name="line.340"></a>
<span class="sourceLineNo">341</span>}<a name="line.341"></a>
</pre>
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