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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.master.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.io.InterruptedIOException;</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.client.VersionInfoUtil;</span>
 <span class="source-line-no">024</span><span id="line-24">import org.apache.hadoop.hbase.procedure2.Procedure;</span>
 <span class="source-line-no">025</span><span id="line-25">import org.apache.yetus.audience.InterfaceAudience;</span>
 <span class="source-line-no">026</span><span id="line-26">import org.apache.yetus.audience.InterfaceStability;</span>
 <span class="source-line-no">027</span><span id="line-27"></span>
 <span class="source-line-no">028</span><span id="line-28">/**</span>
 <span class="source-line-no">029</span><span id="line-29"> * Latch used by the Master to have the prepare() sync behaviour for old clients, that can only get</span>
 <span class="source-line-no">030</span><span id="line-30"> * exceptions in a synchronous way.</span>
 <span class="source-line-no">031</span><span id="line-31"> */</span>
 <span class="source-line-no">032</span><span id="line-32">@InterfaceAudience.Private</span>
 <span class="source-line-no">033</span><span id="line-33">@InterfaceStability.Evolving</span>
 <span class="source-line-no">034</span><span id="line-34">public abstract class ProcedurePrepareLatch {</span>
 <span class="source-line-no">035</span><span id="line-35">  private static final NoopLatch noopLatch = new NoopLatch();</span>
 <span class="source-line-no">036</span><span id="line-36"></span>
 <span class="source-line-no">037</span><span id="line-37">  /**</span>
 <span class="source-line-no">038</span><span id="line-38">   * Create a latch if the client does not have async proc support. This uses the default 1.1</span>
 <span class="source-line-no">039</span><span id="line-39">   * version.</span>
 <span class="source-line-no">040</span><span id="line-40">   * @return a CompatibilityLatch or a NoopLatch if the client has async proc support</span>
 <span class="source-line-no">041</span><span id="line-41">   */</span>
 <span class="source-line-no">042</span><span id="line-42">  public static ProcedurePrepareLatch createLatch() {</span>
 <span class="source-line-no">043</span><span id="line-43">    // don't use the latch if we have procedure support (default 1.1)</span>
 <span class="source-line-no">044</span><span id="line-44">    return createLatch(1, 1);</span>
 <span class="source-line-no">045</span><span id="line-45">  }</span>
 <span class="source-line-no">046</span><span id="line-46"></span>
 <span class="source-line-no">047</span><span id="line-47">  /**</span>
 <span class="source-line-no">048</span><span id="line-48">   * Create a latch if the client does not have async proc support</span>
 <span class="source-line-no">049</span><span id="line-49">   * @param major major version with async proc support</span>
 <span class="source-line-no">050</span><span id="line-50">   * @param minor minor version with async proc support</span>
 <span class="source-line-no">051</span><span id="line-51">   * @return a CompatibilityLatch or a NoopLatch if the client has async proc support</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 ProcedurePrepareLatch createLatch(int major, int minor) {</span>
 <span class="source-line-no">054</span><span id="line-54">    // don't use the latch if we have procedure support</span>
 <span class="source-line-no">055</span><span id="line-55">    return hasProcedureSupport(major, minor) ? noopLatch : new CompatibilityLatch();</span>
 <span class="source-line-no">056</span><span id="line-56">  }</span>
 <span class="source-line-no">057</span><span id="line-57"></span>
 <span class="source-line-no">058</span><span id="line-58">  /**</span>
 <span class="source-line-no">059</span><span id="line-59">   * Creates a latch which blocks.</span>
 <span class="source-line-no">060</span><span id="line-60">   */</span>
 <span class="source-line-no">061</span><span id="line-61">  public static ProcedurePrepareLatch createBlockingLatch() {</span>
 <span class="source-line-no">062</span><span id="line-62">    return new CompatibilityLatch();</span>
 <span class="source-line-no">063</span><span id="line-63">  }</span>
 <span class="source-line-no">064</span><span id="line-64"></span>
 <span class="source-line-no">065</span><span id="line-65">  /**</span>
 <span class="source-line-no">066</span><span id="line-66">   * Returns the singleton latch which does nothing.</span>
 <span class="source-line-no">067</span><span id="line-67">   */</span>
 <span class="source-line-no">068</span><span id="line-68">  public static ProcedurePrepareLatch getNoopLatch() {</span>
 <span class="source-line-no">069</span><span id="line-69">    return noopLatch;</span>
 <span class="source-line-no">070</span><span id="line-70">  }</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 static boolean hasProcedureSupport(int major, int minor) {</span>
 <span class="source-line-no">073</span><span id="line-73">    // Note: this won't work if the shortcut similar to the one in HRegionServer is used</span>
 <span class="source-line-no">074</span><span id="line-74">    // without the corresponding version handling.</span>
 <span class="source-line-no">075</span><span id="line-75">    return VersionInfoUtil.currentClientHasMinimumVersion(major, minor);</span>
 <span class="source-line-no">076</span><span id="line-76">  }</span>
 <span class="source-line-no">077</span><span id="line-77"></span>
 <span class="source-line-no">078</span><span id="line-78">  protected abstract void countDown(final Procedure proc);</span>
 <span class="source-line-no">079</span><span id="line-79"></span>
 <span class="source-line-no">080</span><span id="line-80">  public abstract void await() throws IOException;</span>
 <span class="source-line-no">081</span><span id="line-81"></span>
 <span class="source-line-no">082</span><span id="line-82">  public static void releaseLatch(final ProcedurePrepareLatch latch, final Procedure proc) {</span>
 <span class="source-line-no">083</span><span id="line-83">    if (latch != null) {</span>
 <span class="source-line-no">084</span><span id="line-84">      latch.countDown(proc);</span>
 <span class="source-line-no">085</span><span id="line-85">    }</span>
 <span class="source-line-no">086</span><span id="line-86">  }</span>
 <span class="source-line-no">087</span><span id="line-87"></span>
 <span class="source-line-no">088</span><span id="line-88">  private static class NoopLatch extends ProcedurePrepareLatch {</span>
 <span class="source-line-no">089</span><span id="line-89">    @Override</span>
 <span class="source-line-no">090</span><span id="line-90">    protected void countDown(final Procedure proc) {</span>
 <span class="source-line-no">091</span><span id="line-91">    }</span>
 <span class="source-line-no">092</span><span id="line-92"></span>
 <span class="source-line-no">093</span><span id="line-93">    @Override</span>
 <span class="source-line-no">094</span><span id="line-94">    public void await() throws IOException {</span>
 <span class="source-line-no">095</span><span id="line-95">    }</span>
 <span class="source-line-no">096</span><span id="line-96">  }</span>
 <span class="source-line-no">097</span><span id="line-97"></span>
 <span class="source-line-no">098</span><span id="line-98">  protected static class CompatibilityLatch extends ProcedurePrepareLatch {</span>
 <span class="source-line-no">099</span><span id="line-99">    private final CountDownLatch latch = new CountDownLatch(1);</span>
 <span class="source-line-no">100</span><span id="line-100"></span>
 <span class="source-line-no">101</span><span id="line-101">    private IOException exception = null;</span>
 <span class="source-line-no">102</span><span id="line-102"></span>
 <span class="source-line-no">103</span><span id="line-103">    @Override</span>
 <span class="source-line-no">104</span><span id="line-104">    protected void countDown(final Procedure proc) {</span>
 <span class="source-line-no">105</span><span id="line-105">      if (proc.hasException()) {</span>
 <span class="source-line-no">106</span><span id="line-106">        exception = MasterProcedureUtil.unwrapRemoteIOException(proc);</span>
 <span class="source-line-no">107</span><span id="line-107">      }</span>
 <span class="source-line-no">108</span><span id="line-108">      latch.countDown();</span>
 <span class="source-line-no">109</span><span id="line-109">    }</span>
 <span class="source-line-no">110</span><span id="line-110"></span>
 <span class="source-line-no">111</span><span id="line-111">    @Override</span>
 <span class="source-line-no">112</span><span id="line-112">    public void await() throws IOException {</span>
 <span class="source-line-no">113</span><span id="line-113">      try {</span>
 <span class="source-line-no">114</span><span id="line-114">        latch.await();</span>
 <span class="source-line-no">115</span><span id="line-115">      } catch (InterruptedException e) {</span>
 <span class="source-line-no">116</span><span id="line-116">        throw (InterruptedIOException) new InterruptedIOException().initCause(e);</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">      if (exception != null) {</span>
 <span class="source-line-no">120</span><span id="line-120">        throw exception;</span>
 <span class="source-line-no">121</span><span id="line-121">      }</span>
 <span class="source-line-no">122</span><span id="line-122">    }</span>
 <span class="source-line-no">123</span><span id="line-123">  }</span>
 <span class="source-line-no">124</span><span id="line-124">}</span>


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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.master.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.io.InterruptedIOException;</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.client.VersionInfoUtil;</span>
	<span class="source-line-no">024</span><span id="line-24">import org.apache.hadoop.hbase.procedure2.Procedure;</span>
	<span class="source-line-no">025</span><span id="line-25">import org.apache.yetus.audience.InterfaceAudience;</span>
	<span class="source-line-no">026</span><span id="line-26">import org.apache.yetus.audience.InterfaceStability;</span>
	<span class="source-line-no">027</span><span id="line-27"></span>
	<span class="source-line-no">028</span><span id="line-28">/**</span>
	<span class="source-line-no">029</span><span id="line-29"> * Latch used by the Master to have the prepare() sync behaviour for old clients, that can only get</span>
	<span class="source-line-no">030</span><span id="line-30"> * exceptions in a synchronous way.</span>
	<span class="source-line-no">031</span><span id="line-31"> */</span>
	<span class="source-line-no">032</span><span id="line-32">@InterfaceAudience.Private</span>
	<span class="source-line-no">033</span><span id="line-33">@InterfaceStability.Evolving</span>
	<span class="source-line-no">034</span><span id="line-34">public abstract class ProcedurePrepareLatch {</span>
	<span class="source-line-no">035</span><span id="line-35"> private static final NoopLatch noopLatch = new NoopLatch();</span>
	<span class="source-line-no">036</span><span id="line-36"></span>
	<span class="source-line-no">037</span><span id="line-37"> /**</span>
	<span class="source-line-no">038</span><span id="line-38"> * Create a latch if the client does not have async proc support. This uses the default 1.1</span>
	<span class="source-line-no">039</span><span id="line-39"> * version.</span>
	<span class="source-line-no">040</span><span id="line-40"> * @return a CompatibilityLatch or a NoopLatch if the client has async proc support</span>
	<span class="source-line-no">041</span><span id="line-41"> */</span>
	<span class="source-line-no">042</span><span id="line-42"> public static ProcedurePrepareLatch createLatch() {</span>
	<span class="source-line-no">043</span><span id="line-43"> // don't use the latch if we have procedure support (default 1.1)</span>
	<span class="source-line-no">044</span><span id="line-44"> return createLatch(1, 1);</span>
	<span class="source-line-no">045</span><span id="line-45"> }</span>
	<span class="source-line-no">046</span><span id="line-46"></span>
	<span class="source-line-no">047</span><span id="line-47"> /**</span>
	<span class="source-line-no">048</span><span id="line-48"> * Create a latch if the client does not have async proc support</span>
	<span class="source-line-no">049</span><span id="line-49"> * @param major major version with async proc support</span>
	<span class="source-line-no">050</span><span id="line-50"> * @param minor minor version with async proc support</span>
	<span class="source-line-no">051</span><span id="line-51"> * @return a CompatibilityLatch or a NoopLatch if the client has async proc support</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 ProcedurePrepareLatch createLatch(int major, int minor) {</span>
	<span class="source-line-no">054</span><span id="line-54"> // don't use the latch if we have procedure support</span>
	<span class="source-line-no">055</span><span id="line-55"> return hasProcedureSupport(major, minor) ? noopLatch : new CompatibilityLatch();</span>
	<span class="source-line-no">056</span><span id="line-56"> }</span>
	<span class="source-line-no">057</span><span id="line-57"></span>
	<span class="source-line-no">058</span><span id="line-58"> /**</span>
	<span class="source-line-no">059</span><span id="line-59"> * Creates a latch which blocks.</span>
	<span class="source-line-no">060</span><span id="line-60"> */</span>
	<span class="source-line-no">061</span><span id="line-61"> public static ProcedurePrepareLatch createBlockingLatch() {</span>
	<span class="source-line-no">062</span><span id="line-62"> return new CompatibilityLatch();</span>
	<span class="source-line-no">063</span><span id="line-63"> }</span>
	<span class="source-line-no">064</span><span id="line-64"></span>
	<span class="source-line-no">065</span><span id="line-65"> /**</span>
	<span class="source-line-no">066</span><span id="line-66"> * Returns the singleton latch which does nothing.</span>
	<span class="source-line-no">067</span><span id="line-67"> */</span>
	<span class="source-line-no">068</span><span id="line-68"> public static ProcedurePrepareLatch getNoopLatch() {</span>
	<span class="source-line-no">069</span><span id="line-69"> return noopLatch;</span>
	<span class="source-line-no">070</span><span id="line-70"> }</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 static boolean hasProcedureSupport(int major, int minor) {</span>
	<span class="source-line-no">073</span><span id="line-73"> // Note: this won't work if the shortcut similar to the one in HRegionServer is used</span>
	<span class="source-line-no">074</span><span id="line-74"> // without the corresponding version handling.</span>
	<span class="source-line-no">075</span><span id="line-75"> return VersionInfoUtil.currentClientHasMinimumVersion(major, minor);</span>
	<span class="source-line-no">076</span><span id="line-76"> }</span>
	<span class="source-line-no">077</span><span id="line-77"></span>
	<span class="source-line-no">078</span><span id="line-78"> protected abstract void countDown(final Procedure proc);</span>
	<span class="source-line-no">079</span><span id="line-79"></span>
	<span class="source-line-no">080</span><span id="line-80"> public abstract void await() throws IOException;</span>
	<span class="source-line-no">081</span><span id="line-81"></span>
	<span class="source-line-no">082</span><span id="line-82"> public static void releaseLatch(final ProcedurePrepareLatch latch, final Procedure proc) {</span>
	<span class="source-line-no">083</span><span id="line-83"> if (latch != null) {</span>
	<span class="source-line-no">084</span><span id="line-84"> latch.countDown(proc);</span>
	<span class="source-line-no">085</span><span id="line-85"> }</span>
	<span class="source-line-no">086</span><span id="line-86"> }</span>
	<span class="source-line-no">087</span><span id="line-87"></span>
	<span class="source-line-no">088</span><span id="line-88"> private static class NoopLatch extends ProcedurePrepareLatch {</span>
	<span class="source-line-no">089</span><span id="line-89"> @Override</span>
	<span class="source-line-no">090</span><span id="line-90"> protected void countDown(final Procedure proc) {</span>
	<span class="source-line-no">091</span><span id="line-91"> }</span>
	<span class="source-line-no">092</span><span id="line-92"></span>
	<span class="source-line-no">093</span><span id="line-93"> @Override</span>
	<span class="source-line-no">094</span><span id="line-94"> public void await() throws IOException {</span>
	<span class="source-line-no">095</span><span id="line-95"> }</span>
	<span class="source-line-no">096</span><span id="line-96"> }</span>
	<span class="source-line-no">097</span><span id="line-97"></span>
	<span class="source-line-no">098</span><span id="line-98"> protected static class CompatibilityLatch extends ProcedurePrepareLatch {</span>
	<span class="source-line-no">099</span><span id="line-99"> private final CountDownLatch latch = new CountDownLatch(1);</span>
	<span class="source-line-no">100</span><span id="line-100"></span>
	<span class="source-line-no">101</span><span id="line-101"> private IOException exception = null;</span>
	<span class="source-line-no">102</span><span id="line-102"></span>
	<span class="source-line-no">103</span><span id="line-103"> @Override</span>
	<span class="source-line-no">104</span><span id="line-104"> protected void countDown(final Procedure proc) {</span>
	<span class="source-line-no">105</span><span id="line-105"> if (proc.hasException()) {</span>
	<span class="source-line-no">106</span><span id="line-106"> exception = MasterProcedureUtil.unwrapRemoteIOException(proc);</span>
	<span class="source-line-no">107</span><span id="line-107"> }</span>
	<span class="source-line-no">108</span><span id="line-108"> latch.countDown();</span>
	<span class="source-line-no">109</span><span id="line-109"> }</span>
	<span class="source-line-no">110</span><span id="line-110"></span>
	<span class="source-line-no">111</span><span id="line-111"> @Override</span>
	<span class="source-line-no">112</span><span id="line-112"> public void await() throws IOException {</span>
	<span class="source-line-no">113</span><span id="line-113"> try {</span>
	<span class="source-line-no">114</span><span id="line-114"> latch.await();</span>
	<span class="source-line-no">115</span><span id="line-115"> } catch (InterruptedException e) {</span>
	<span class="source-line-no">116</span><span id="line-116"> throw (InterruptedIOException) new InterruptedIOException().initCause(e);</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"> if (exception != null) {</span>
	<span class="source-line-no">120</span><span id="line-120"> throw exception;</span>
	<span class="source-line-no">121</span><span id="line-121"> }</span>
	<span class="source-line-no">122</span><span id="line-122"> }</span>
	<span class="source-line-no">123</span><span id="line-123"> }</span>
	<span class="source-line-no">124</span><span id="line-124">}</span>




























































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