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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.client.example;<a name="line.18"></a>
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>import static org.apache.hadoop.hbase.util.FutureUtils.addListener;<a name="line.20"></a>
<span class="sourceLineNo">021</span><a name="line.21"></a>
<span class="sourceLineNo">022</span>import java.util.concurrent.CompletableFuture;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import java.util.concurrent.CountDownLatch;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import java.util.concurrent.ExecutorService;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import java.util.concurrent.Executors;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import java.util.concurrent.atomic.AtomicReference;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import java.util.stream.IntStream;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import org.apache.commons.io.IOUtils;<a name="line.28"></a>
<span class="sourceLineNo">029</span>import org.apache.hadoop.conf.Configured;<a name="line.29"></a>
<span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.TableName;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import org.apache.hadoop.hbase.client.AsyncConnection;<a name="line.31"></a>
<span class="sourceLineNo">032</span>import org.apache.hadoop.hbase.client.AsyncTable;<a name="line.32"></a>
<span class="sourceLineNo">033</span>import org.apache.hadoop.hbase.client.ConnectionFactory;<a name="line.33"></a>
<span class="sourceLineNo">034</span>import org.apache.hadoop.hbase.client.Get;<a name="line.34"></a>
<span class="sourceLineNo">035</span>import org.apache.hadoop.hbase.client.Put;<a name="line.35"></a>
<span class="sourceLineNo">036</span>import org.apache.hadoop.hbase.util.Bytes;<a name="line.36"></a>
<span class="sourceLineNo">037</span>import org.apache.hadoop.hbase.util.Threads;<a name="line.37"></a>
<span class="sourceLineNo">038</span>import org.apache.hadoop.util.Tool;<a name="line.38"></a>
<span class="sourceLineNo">039</span>import org.apache.hadoop.util.ToolRunner;<a name="line.39"></a>
<span class="sourceLineNo">040</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.40"></a>
<span class="sourceLineNo">041</span>import org.slf4j.Logger;<a name="line.41"></a>
<span class="sourceLineNo">042</span>import org.slf4j.LoggerFactory;<a name="line.42"></a>
<span class="sourceLineNo">043</span><a name="line.43"></a>
<span class="sourceLineNo">044</span>import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;<a name="line.44"></a>
<span class="sourceLineNo">045</span><a name="line.45"></a>
<span class="sourceLineNo">046</span>/**<a name="line.46"></a>
<span class="sourceLineNo">047</span> * A simple example shows how to use asynchronous client.<a name="line.47"></a>
<span class="sourceLineNo">048</span> */<a name="line.48"></a>
<span class="sourceLineNo">049</span>@InterfaceAudience.Private<a name="line.49"></a>
<span class="sourceLineNo">050</span>public class AsyncClientExample extends Configured implements Tool {<a name="line.50"></a>
<span class="sourceLineNo">051</span><a name="line.51"></a>
<span class="sourceLineNo">052</span> private static final Logger LOG = LoggerFactory.getLogger(AsyncClientExample.class);<a name="line.52"></a>
<span class="sourceLineNo">053</span><a name="line.53"></a>
<span class="sourceLineNo">054</span> /**<a name="line.54"></a>
<span class="sourceLineNo">055</span> * The size for thread pool.<a name="line.55"></a>
<span class="sourceLineNo">056</span> */<a name="line.56"></a>
<span class="sourceLineNo">057</span> private static final int THREAD_POOL_SIZE = 16;<a name="line.57"></a>
<span class="sourceLineNo">058</span><a name="line.58"></a>
<span class="sourceLineNo">059</span> /**<a name="line.59"></a>
<span class="sourceLineNo">060</span> * The default number of operations.<a name="line.60"></a>
<span class="sourceLineNo">061</span> */<a name="line.61"></a>
<span class="sourceLineNo">062</span> private static final int DEFAULT_NUM_OPS = 100;<a name="line.62"></a>
<span class="sourceLineNo">063</span><a name="line.63"></a>
<span class="sourceLineNo">064</span> /**<a name="line.64"></a>
<span class="sourceLineNo">065</span> * The name of the column family. d for default.<a name="line.65"></a>
<span class="sourceLineNo">066</span> */<a name="line.66"></a>
<span class="sourceLineNo">067</span> private static final byte[] FAMILY = Bytes.toBytes("d");<a name="line.67"></a>
<span class="sourceLineNo">068</span><a name="line.68"></a>
<span class="sourceLineNo">069</span> /**<a name="line.69"></a>
<span class="sourceLineNo">070</span> * For the example we're just using one qualifier.<a name="line.70"></a>
<span class="sourceLineNo">071</span> */<a name="line.71"></a>
<span class="sourceLineNo">072</span> private static final byte[] QUAL = Bytes.toBytes("test");<a name="line.72"></a>
<span class="sourceLineNo">073</span><a name="line.73"></a>
<span class="sourceLineNo">074</span> private final AtomicReference&lt;CompletableFuture&lt;AsyncConnection&gt;&gt; future =<a name="line.74"></a>
<span class="sourceLineNo">075</span> new AtomicReference&lt;&gt;();<a name="line.75"></a>
<span class="sourceLineNo">076</span><a name="line.76"></a>
<span class="sourceLineNo">077</span> private CompletableFuture&lt;AsyncConnection&gt; getConn() {<a name="line.77"></a>
<span class="sourceLineNo">078</span> CompletableFuture&lt;AsyncConnection&gt; f = future.get();<a name="line.78"></a>
<span class="sourceLineNo">079</span> if (f != null) {<a name="line.79"></a>
<span class="sourceLineNo">080</span> return f;<a name="line.80"></a>
<span class="sourceLineNo">081</span> }<a name="line.81"></a>
<span class="sourceLineNo">082</span> for (;;) {<a name="line.82"></a>
<span class="sourceLineNo">083</span> if (future.compareAndSet(null, new CompletableFuture&lt;&gt;())) {<a name="line.83"></a>
<span class="sourceLineNo">084</span> CompletableFuture&lt;AsyncConnection&gt; toComplete = future.get();<a name="line.84"></a>
<span class="sourceLineNo">085</span> addListener(ConnectionFactory.createAsyncConnection(getConf()), (conn, error) -&gt; {<a name="line.85"></a>
<span class="sourceLineNo">086</span> if (error != null) {<a name="line.86"></a>
<span class="sourceLineNo">087</span> toComplete.completeExceptionally(error);<a name="line.87"></a>
<span class="sourceLineNo">088</span> // we need to reset the future holder so we will get a chance to recreate an async<a name="line.88"></a>
<span class="sourceLineNo">089</span> // connection at next try.<a name="line.89"></a>
<span class="sourceLineNo">090</span> future.set(null);<a name="line.90"></a>
<span class="sourceLineNo">091</span> return;<a name="line.91"></a>
<span class="sourceLineNo">092</span> }<a name="line.92"></a>
<span class="sourceLineNo">093</span> toComplete.complete(conn);<a name="line.93"></a>
<span class="sourceLineNo">094</span> });<a name="line.94"></a>
<span class="sourceLineNo">095</span> return toComplete;<a name="line.95"></a>
<span class="sourceLineNo">096</span> } else {<a name="line.96"></a>
<span class="sourceLineNo">097</span> f = future.get();<a name="line.97"></a>
<span class="sourceLineNo">098</span> if (f != null) {<a name="line.98"></a>
<span class="sourceLineNo">099</span> return f;<a name="line.99"></a>
<span class="sourceLineNo">100</span> }<a name="line.100"></a>
<span class="sourceLineNo">101</span> }<a name="line.101"></a>
<span class="sourceLineNo">102</span> }<a name="line.102"></a>
<span class="sourceLineNo">103</span> }<a name="line.103"></a>
<span class="sourceLineNo">104</span><a name="line.104"></a>
<span class="sourceLineNo">105</span> @edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "NP_NONNULL_PARAM_VIOLATION",<a name="line.105"></a>
<span class="sourceLineNo">106</span> justification = "it is valid to pass NULL to CompletableFuture#completedFuture")<a name="line.106"></a>
<span class="sourceLineNo">107</span> private CompletableFuture&lt;Void&gt; closeConn() {<a name="line.107"></a>
<span class="sourceLineNo">108</span> CompletableFuture&lt;AsyncConnection&gt; f = future.get();<a name="line.108"></a>
<span class="sourceLineNo">109</span> if (f == null) {<a name="line.109"></a>
<span class="sourceLineNo">110</span> return CompletableFuture.completedFuture(null);<a name="line.110"></a>
<span class="sourceLineNo">111</span> }<a name="line.111"></a>
<span class="sourceLineNo">112</span> CompletableFuture&lt;Void&gt; closeFuture = new CompletableFuture&lt;&gt;();<a name="line.112"></a>
<span class="sourceLineNo">113</span> addListener(f, (conn, error) -&gt; {<a name="line.113"></a>
<span class="sourceLineNo">114</span> if (error == null) {<a name="line.114"></a>
<span class="sourceLineNo">115</span> IOUtils.closeQuietly(conn, e -&gt; LOG.warn("failed to close conn", e));<a name="line.115"></a>
<span class="sourceLineNo">116</span> }<a name="line.116"></a>
<span class="sourceLineNo">117</span> closeFuture.complete(null);<a name="line.117"></a>
<span class="sourceLineNo">118</span> });<a name="line.118"></a>
<span class="sourceLineNo">119</span> return closeFuture;<a name="line.119"></a>
<span class="sourceLineNo">120</span> }<a name="line.120"></a>
<span class="sourceLineNo">121</span><a name="line.121"></a>
<span class="sourceLineNo">122</span> private byte[] getKey(int i) {<a name="line.122"></a>
<span class="sourceLineNo">123</span> return Bytes.toBytes(String.format("%08x", i));<a name="line.123"></a>
<span class="sourceLineNo">124</span> }<a name="line.124"></a>
<span class="sourceLineNo">125</span><a name="line.125"></a>
<span class="sourceLineNo">126</span> @Override<a name="line.126"></a>
<span class="sourceLineNo">127</span> public int run(String[] args) throws Exception {<a name="line.127"></a>
<span class="sourceLineNo">128</span> if (args.length &lt; 1 || args.length &gt; 2) {<a name="line.128"></a>
<span class="sourceLineNo">129</span> System.out.println("Usage: " + this.getClass().getName() + " tableName [num_operations]");<a name="line.129"></a>
<span class="sourceLineNo">130</span> return -1;<a name="line.130"></a>
<span class="sourceLineNo">131</span> }<a name="line.131"></a>
<span class="sourceLineNo">132</span> TableName tableName = TableName.valueOf(args[0]);<a name="line.132"></a>
<span class="sourceLineNo">133</span> int numOps = args.length &gt; 1 ? Integer.parseInt(args[1]) : DEFAULT_NUM_OPS;<a name="line.133"></a>
<span class="sourceLineNo">134</span> ExecutorService threadPool = Executors.newFixedThreadPool(THREAD_POOL_SIZE,<a name="line.134"></a>
<span class="sourceLineNo">135</span> new ThreadFactoryBuilder().setNameFormat("AsyncClientExample-pool-%d").setDaemon(true)<a name="line.135"></a>
<span class="sourceLineNo">136</span> .setUncaughtExceptionHandler(Threads.LOGGING_EXCEPTION_HANDLER).build());<a name="line.136"></a>
<span class="sourceLineNo">137</span> // We use AsyncTable here so we need to provide a separated thread pool. RawAsyncTable does not<a name="line.137"></a>
<span class="sourceLineNo">138</span> // need a thread pool and may have a better performance if you use it correctly as it can save<a name="line.138"></a>
<span class="sourceLineNo">139</span> // some context switches. But if you use RawAsyncTable incorrectly, you may have a very bad<a name="line.139"></a>
<span class="sourceLineNo">140</span> // impact on performance so use it with caution.<a name="line.140"></a>
<span class="sourceLineNo">141</span> CountDownLatch latch = new CountDownLatch(numOps);<a name="line.141"></a>
<span class="sourceLineNo">142</span> IntStream.range(0, numOps).forEach(i -&gt; {<a name="line.142"></a>
<span class="sourceLineNo">143</span> CompletableFuture&lt;AsyncConnection&gt; future = getConn();<a name="line.143"></a>
<span class="sourceLineNo">144</span> addListener(future, (conn, error) -&gt; {<a name="line.144"></a>
<span class="sourceLineNo">145</span> if (error != null) {<a name="line.145"></a>
<span class="sourceLineNo">146</span> LOG.warn("failed to get async connection for " + i, error);<a name="line.146"></a>
<span class="sourceLineNo">147</span> latch.countDown();<a name="line.147"></a>
<span class="sourceLineNo">148</span> return;<a name="line.148"></a>
<span class="sourceLineNo">149</span> }<a name="line.149"></a>
<span class="sourceLineNo">150</span> AsyncTable&lt;?&gt; table = conn.getTable(tableName, threadPool);<a name="line.150"></a>
<span class="sourceLineNo">151</span> addListener(table.put(new Put(getKey(i)).addColumn(FAMILY, QUAL, Bytes.toBytes(i))),<a name="line.151"></a>
<span class="sourceLineNo">152</span> (putResp, putErr) -&gt; {<a name="line.152"></a>
<span class="sourceLineNo">153</span> if (putErr != null) {<a name="line.153"></a>
<span class="sourceLineNo">154</span> LOG.warn("put failed for " + i, putErr);<a name="line.154"></a>
<span class="sourceLineNo">155</span> latch.countDown();<a name="line.155"></a>
<span class="sourceLineNo">156</span> return;<a name="line.156"></a>
<span class="sourceLineNo">157</span> }<a name="line.157"></a>
<span class="sourceLineNo">158</span> LOG.info("put for " + i + " succeeded, try getting");<a name="line.158"></a>
<span class="sourceLineNo">159</span> addListener(table.get(new Get(getKey(i))), (result, getErr) -&gt; {<a name="line.159"></a>
<span class="sourceLineNo">160</span> if (getErr != null) {<a name="line.160"></a>
<span class="sourceLineNo">161</span> LOG.warn("get failed for " + i);<a name="line.161"></a>
<span class="sourceLineNo">162</span> latch.countDown();<a name="line.162"></a>
<span class="sourceLineNo">163</span> return;<a name="line.163"></a>
<span class="sourceLineNo">164</span> }<a name="line.164"></a>
<span class="sourceLineNo">165</span> if (result.isEmpty()) {<a name="line.165"></a>
<span class="sourceLineNo">166</span> LOG.warn("get failed for " + i + ", server returns empty result");<a name="line.166"></a>
<span class="sourceLineNo">167</span> } else if (!result.containsColumn(FAMILY, QUAL)) {<a name="line.167"></a>
<span class="sourceLineNo">168</span> LOG.warn("get failed for " + i + ", the result does not contain "<a name="line.168"></a>
<span class="sourceLineNo">169</span> + Bytes.toString(FAMILY) + ":" + Bytes.toString(QUAL));<a name="line.169"></a>
<span class="sourceLineNo">170</span> } else {<a name="line.170"></a>
<span class="sourceLineNo">171</span> int v = Bytes.toInt(result.getValue(FAMILY, QUAL));<a name="line.171"></a>
<span class="sourceLineNo">172</span> if (v != i) {<a name="line.172"></a>
<span class="sourceLineNo">173</span> LOG.warn("get failed for " + i + ", the value of " + Bytes.toString(FAMILY) + ":"<a name="line.173"></a>
<span class="sourceLineNo">174</span> + Bytes.toString(QUAL) + " is " + v + ", exected " + i);<a name="line.174"></a>
<span class="sourceLineNo">175</span> } else {<a name="line.175"></a>
<span class="sourceLineNo">176</span> LOG.info("get for " + i + " succeeded");<a name="line.176"></a>
<span class="sourceLineNo">177</span> }<a name="line.177"></a>
<span class="sourceLineNo">178</span> }<a name="line.178"></a>
<span class="sourceLineNo">179</span> latch.countDown();<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> });<a name="line.182"></a>
<span class="sourceLineNo">183</span> });<a name="line.183"></a>
<span class="sourceLineNo">184</span> latch.await();<a name="line.184"></a>
<span class="sourceLineNo">185</span> closeConn().get();<a name="line.185"></a>
<span class="sourceLineNo">186</span> return 0;<a name="line.186"></a>
<span class="sourceLineNo">187</span> }<a name="line.187"></a>
<span class="sourceLineNo">188</span><a name="line.188"></a>
<span class="sourceLineNo">189</span> public static void main(String[] args) throws Exception {<a name="line.189"></a>
<span class="sourceLineNo">190</span> ToolRunner.run(new AsyncClientExample(), args);<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>
</pre>
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