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<FONT color="green">001</FONT>    /**<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<FONT color="green">003</FONT>     * or more contributor license agreements.  See the NOTICE file<a name="line.3"></a>
<FONT color="green">004</FONT>     * distributed with this work for additional information<a name="line.4"></a>
<FONT color="green">005</FONT>     * regarding copyright ownership.  The ASF licenses this file<a name="line.5"></a>
<FONT color="green">006</FONT>     * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
<FONT color="green">007</FONT>     * "License"); you may not use this file except in compliance<a name="line.7"></a>
<FONT color="green">008</FONT>     * with the License.  You may obtain a copy of the License at<a name="line.8"></a>
<FONT color="green">009</FONT>     *<a name="line.9"></a>
<FONT color="green">010</FONT>     *     http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<FONT color="green">011</FONT>     *<a name="line.11"></a>
<FONT color="green">012</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
<FONT color="green">013</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
<FONT color="green">014</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
<FONT color="green">015</FONT>     * See the License for the specific language governing permissions and<a name="line.15"></a>
<FONT color="green">016</FONT>     * limitations under the License.<a name="line.16"></a>
<FONT color="green">017</FONT>     */<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    package org.apache.hadoop.mapreduce.lib.join;<a name="line.19"></a>
<FONT color="green">020</FONT>    <a name="line.20"></a>
<FONT color="green">021</FONT>    import java.io.IOException;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>    import org.apache.hadoop.classification.InterfaceAudience;<a name="line.23"></a>
<FONT color="green">024</FONT>    import org.apache.hadoop.classification.InterfaceStability;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.apache.hadoop.conf.Configuration;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.apache.hadoop.io.NullWritable;<a name="line.26"></a>
<FONT color="green">027</FONT>    import org.apache.hadoop.io.Writable;<a name="line.27"></a>
<FONT color="green">028</FONT>    import org.apache.hadoop.io.WritableComparable;<a name="line.28"></a>
<FONT color="green">029</FONT>    import org.apache.hadoop.io.WritableComparator;<a name="line.29"></a>
<FONT color="green">030</FONT>    import org.apache.hadoop.mapreduce.InputSplit;<a name="line.30"></a>
<FONT color="green">031</FONT>    import org.apache.hadoop.mapreduce.RecordReader;<a name="line.31"></a>
<FONT color="green">032</FONT>    import org.apache.hadoop.mapreduce.TaskAttemptContext;<a name="line.32"></a>
<FONT color="green">033</FONT>    import org.apache.hadoop.util.ReflectionUtils;<a name="line.33"></a>
<FONT color="green">034</FONT>    <a name="line.34"></a>
<FONT color="green">035</FONT>    /**<a name="line.35"></a>
<FONT color="green">036</FONT>     * Proxy class for a RecordReader participating in the join framework.<a name="line.36"></a>
<FONT color="green">037</FONT>     * <a name="line.37"></a>
<FONT color="green">038</FONT>     * This class keeps track of the &amp;quot;head&amp;quot; key-value pair for the<a name="line.38"></a>
<FONT color="green">039</FONT>     * provided RecordReader and keeps a store of values matching a key when<a name="line.39"></a>
<FONT color="green">040</FONT>     * this source is participating in a join.<a name="line.40"></a>
<FONT color="green">041</FONT>     */<a name="line.41"></a>
<FONT color="green">042</FONT>    @InterfaceAudience.Public<a name="line.42"></a>
<FONT color="green">043</FONT>    @InterfaceStability.Stable<a name="line.43"></a>
<FONT color="green">044</FONT>    public class WrappedRecordReader&lt;K extends WritableComparable&lt;?&gt;,<a name="line.44"></a>
<FONT color="green">045</FONT>        U extends Writable&gt; extends ComposableRecordReader&lt;K,U&gt; {<a name="line.45"></a>
<FONT color="green">046</FONT>    <a name="line.46"></a>
<FONT color="green">047</FONT>      protected boolean empty = false;<a name="line.47"></a>
<FONT color="green">048</FONT>      private RecordReader&lt;K,U&gt; rr;<a name="line.48"></a>
<FONT color="green">049</FONT>      private int id;  // index at which values will be inserted in collector<a name="line.49"></a>
<FONT color="green">050</FONT>    <a name="line.50"></a>
<FONT color="green">051</FONT>      protected WritableComparator cmp = null;<a name="line.51"></a>
<FONT color="green">052</FONT>      private K key; // key at the top of this RR<a name="line.52"></a>
<FONT color="green">053</FONT>      private U value; // value assoc with key<a name="line.53"></a>
<FONT color="green">054</FONT>      private ResetableIterator&lt;U&gt; vjoin;<a name="line.54"></a>
<FONT color="green">055</FONT>      private Configuration conf = new Configuration();<a name="line.55"></a>
<FONT color="green">056</FONT>      @SuppressWarnings("unchecked")<a name="line.56"></a>
<FONT color="green">057</FONT>      private Class&lt;? extends WritableComparable&gt; keyclass = null; <a name="line.57"></a>
<FONT color="green">058</FONT>      private Class&lt;? extends Writable&gt; valueclass = null; <a name="line.58"></a>
<FONT color="green">059</FONT>      <a name="line.59"></a>
<FONT color="green">060</FONT>      protected WrappedRecordReader(int id) {<a name="line.60"></a>
<FONT color="green">061</FONT>        this.id = id;<a name="line.61"></a>
<FONT color="green">062</FONT>        vjoin = new StreamBackedIterator&lt;U&gt;();<a name="line.62"></a>
<FONT color="green">063</FONT>      }<a name="line.63"></a>
<FONT color="green">064</FONT>      <a name="line.64"></a>
<FONT color="green">065</FONT>      /**<a name="line.65"></a>
<FONT color="green">066</FONT>       * For a given RecordReader rr, occupy position id in collector.<a name="line.66"></a>
<FONT color="green">067</FONT>       */<a name="line.67"></a>
<FONT color="green">068</FONT>      WrappedRecordReader(int id, RecordReader&lt;K,U&gt; rr,<a name="line.68"></a>
<FONT color="green">069</FONT>          Class&lt;? extends WritableComparator&gt; cmpcl) <a name="line.69"></a>
<FONT color="green">070</FONT>      throws IOException, InterruptedException {<a name="line.70"></a>
<FONT color="green">071</FONT>        this.id = id;<a name="line.71"></a>
<FONT color="green">072</FONT>        this.rr = rr;<a name="line.72"></a>
<FONT color="green">073</FONT>        if (cmpcl != null) {<a name="line.73"></a>
<FONT color="green">074</FONT>          try {<a name="line.74"></a>
<FONT color="green">075</FONT>            this.cmp = cmpcl.newInstance();<a name="line.75"></a>
<FONT color="green">076</FONT>          } catch (InstantiationException e) {<a name="line.76"></a>
<FONT color="green">077</FONT>            throw new IOException(e);<a name="line.77"></a>
<FONT color="green">078</FONT>          } catch (IllegalAccessException e) {<a name="line.78"></a>
<FONT color="green">079</FONT>            throw new IOException(e);<a name="line.79"></a>
<FONT color="green">080</FONT>          }<a name="line.80"></a>
<FONT color="green">081</FONT>        }<a name="line.81"></a>
<FONT color="green">082</FONT>        vjoin = new StreamBackedIterator&lt;U&gt;();<a name="line.82"></a>
<FONT color="green">083</FONT>      }<a name="line.83"></a>
<FONT color="green">084</FONT>    <a name="line.84"></a>
<FONT color="green">085</FONT>      public void initialize(InputSplit split,<a name="line.85"></a>
<FONT color="green">086</FONT>                             TaskAttemptContext context)<a name="line.86"></a>
<FONT color="green">087</FONT>      throws IOException, InterruptedException {<a name="line.87"></a>
<FONT color="green">088</FONT>        rr.initialize(split, context);<a name="line.88"></a>
<FONT color="green">089</FONT>        conf = context.getConfiguration();<a name="line.89"></a>
<FONT color="green">090</FONT>        nextKeyValue();<a name="line.90"></a>
<FONT color="green">091</FONT>        if (!empty) {<a name="line.91"></a>
<FONT color="green">092</FONT>          keyclass = key.getClass().asSubclass(WritableComparable.class);<a name="line.92"></a>
<FONT color="green">093</FONT>          valueclass = value.getClass();<a name="line.93"></a>
<FONT color="green">094</FONT>          if (cmp == null) {<a name="line.94"></a>
<FONT color="green">095</FONT>            cmp = WritableComparator.get(keyclass);<a name="line.95"></a>
<FONT color="green">096</FONT>          }<a name="line.96"></a>
<FONT color="green">097</FONT>        }<a name="line.97"></a>
<FONT color="green">098</FONT>      }<a name="line.98"></a>
<FONT color="green">099</FONT>    <a name="line.99"></a>
<FONT color="green">100</FONT>      /**<a name="line.100"></a>
<FONT color="green">101</FONT>       * Request new key from proxied RR.<a name="line.101"></a>
<FONT color="green">102</FONT>       */<a name="line.102"></a>
<FONT color="green">103</FONT>      @SuppressWarnings("unchecked")<a name="line.103"></a>
<FONT color="green">104</FONT>      public K createKey() {<a name="line.104"></a>
<FONT color="green">105</FONT>        if (keyclass != null) {<a name="line.105"></a>
<FONT color="green">106</FONT>          return (K) ReflectionUtils.newInstance(keyclass, conf);<a name="line.106"></a>
<FONT color="green">107</FONT>        }<a name="line.107"></a>
<FONT color="green">108</FONT>        return (K) NullWritable.get();<a name="line.108"></a>
<FONT color="green">109</FONT>      }<a name="line.109"></a>
<FONT color="green">110</FONT>      <a name="line.110"></a>
<FONT color="green">111</FONT>      @SuppressWarnings("unchecked")<a name="line.111"></a>
<FONT color="green">112</FONT>      public U createValue() {<a name="line.112"></a>
<FONT color="green">113</FONT>        if (valueclass != null) {<a name="line.113"></a>
<FONT color="green">114</FONT>          return (U) ReflectionUtils.newInstance(valueclass, conf);<a name="line.114"></a>
<FONT color="green">115</FONT>        }<a name="line.115"></a>
<FONT color="green">116</FONT>        return (U) NullWritable.get();<a name="line.116"></a>
<FONT color="green">117</FONT>      }<a name="line.117"></a>
<FONT color="green">118</FONT>      <a name="line.118"></a>
<FONT color="green">119</FONT>      /** {@inheritDoc} */<a name="line.119"></a>
<FONT color="green">120</FONT>      public int id() {<a name="line.120"></a>
<FONT color="green">121</FONT>        return id;<a name="line.121"></a>
<FONT color="green">122</FONT>      }<a name="line.122"></a>
<FONT color="green">123</FONT>    <a name="line.123"></a>
<FONT color="green">124</FONT>      /**<a name="line.124"></a>
<FONT color="green">125</FONT>       * Return the key at the head of this RR.<a name="line.125"></a>
<FONT color="green">126</FONT>       */<a name="line.126"></a>
<FONT color="green">127</FONT>      public K key() {<a name="line.127"></a>
<FONT color="green">128</FONT>        return key;<a name="line.128"></a>
<FONT color="green">129</FONT>      }<a name="line.129"></a>
<FONT color="green">130</FONT>    <a name="line.130"></a>
<FONT color="green">131</FONT>      /**<a name="line.131"></a>
<FONT color="green">132</FONT>       * Clone the key at the head of this RR into the object supplied.<a name="line.132"></a>
<FONT color="green">133</FONT>       */<a name="line.133"></a>
<FONT color="green">134</FONT>      public void key(K qkey) throws IOException {<a name="line.134"></a>
<FONT color="green">135</FONT>        ReflectionUtils.copy(conf, key, qkey);<a name="line.135"></a>
<FONT color="green">136</FONT>      }<a name="line.136"></a>
<FONT color="green">137</FONT>    <a name="line.137"></a>
<FONT color="green">138</FONT>      /**<a name="line.138"></a>
<FONT color="green">139</FONT>       * Return true if the RR- including the k,v pair stored in this object-<a name="line.139"></a>
<FONT color="green">140</FONT>       * is exhausted.<a name="line.140"></a>
<FONT color="green">141</FONT>       */<a name="line.141"></a>
<FONT color="green">142</FONT>      public boolean hasNext() {<a name="line.142"></a>
<FONT color="green">143</FONT>        return !empty;<a name="line.143"></a>
<FONT color="green">144</FONT>      }<a name="line.144"></a>
<FONT color="green">145</FONT>    <a name="line.145"></a>
<FONT color="green">146</FONT>      /**<a name="line.146"></a>
<FONT color="green">147</FONT>       * Skip key-value pairs with keys less than or equal to the key provided.<a name="line.147"></a>
<FONT color="green">148</FONT>       */<a name="line.148"></a>
<FONT color="green">149</FONT>      public void skip(K key) throws IOException, InterruptedException {<a name="line.149"></a>
<FONT color="green">150</FONT>        if (hasNext()) {<a name="line.150"></a>
<FONT color="green">151</FONT>          while (cmp.compare(key(), key) &lt;= 0 &amp;&amp; next());<a name="line.151"></a>
<FONT color="green">152</FONT>        }<a name="line.152"></a>
<FONT color="green">153</FONT>      }<a name="line.153"></a>
<FONT color="green">154</FONT>    <a name="line.154"></a>
<FONT color="green">155</FONT>      /**<a name="line.155"></a>
<FONT color="green">156</FONT>       * Add an iterator to the collector at the position occupied by this<a name="line.156"></a>
<FONT color="green">157</FONT>       * RecordReader over the values in this stream paired with the key<a name="line.157"></a>
<FONT color="green">158</FONT>       * provided (ie register a stream of values from this source matching K<a name="line.158"></a>
<FONT color="green">159</FONT>       * with a collector).<a name="line.159"></a>
<FONT color="green">160</FONT>       */<a name="line.160"></a>
<FONT color="green">161</FONT>      @SuppressWarnings("unchecked")<a name="line.161"></a>
<FONT color="green">162</FONT>      public void accept(CompositeRecordReader.JoinCollector i, K key)<a name="line.162"></a>
<FONT color="green">163</FONT>          throws IOException, InterruptedException {<a name="line.163"></a>
<FONT color="green">164</FONT>        vjoin.clear();<a name="line.164"></a>
<FONT color="green">165</FONT>        if (key() != null &amp;&amp; 0 == cmp.compare(key, key())) {<a name="line.165"></a>
<FONT color="green">166</FONT>          do {<a name="line.166"></a>
<FONT color="green">167</FONT>            vjoin.add(value);<a name="line.167"></a>
<FONT color="green">168</FONT>          } while (next() &amp;&amp; 0 == cmp.compare(key, key()));<a name="line.168"></a>
<FONT color="green">169</FONT>        }<a name="line.169"></a>
<FONT color="green">170</FONT>        i.add(id, vjoin);<a name="line.170"></a>
<FONT color="green">171</FONT>      }<a name="line.171"></a>
<FONT color="green">172</FONT>    <a name="line.172"></a>
<FONT color="green">173</FONT>      /**<a name="line.173"></a>
<FONT color="green">174</FONT>       * Read the next k,v pair into the head of this object; return true iff<a name="line.174"></a>
<FONT color="green">175</FONT>       * the RR and this are exhausted.<a name="line.175"></a>
<FONT color="green">176</FONT>       */<a name="line.176"></a>
<FONT color="green">177</FONT>      public boolean nextKeyValue() throws IOException, InterruptedException {<a name="line.177"></a>
<FONT color="green">178</FONT>        if (hasNext()) {<a name="line.178"></a>
<FONT color="green">179</FONT>          next();<a name="line.179"></a>
<FONT color="green">180</FONT>          return true;<a name="line.180"></a>
<FONT color="green">181</FONT>        }<a name="line.181"></a>
<FONT color="green">182</FONT>        return false;<a name="line.182"></a>
<FONT color="green">183</FONT>      }<a name="line.183"></a>
<FONT color="green">184</FONT>    <a name="line.184"></a>
<FONT color="green">185</FONT>      /**<a name="line.185"></a>
<FONT color="green">186</FONT>       * Read the next k,v pair into the head of this object; return true iff<a name="line.186"></a>
<FONT color="green">187</FONT>       * the RR and this are exhausted.<a name="line.187"></a>
<FONT color="green">188</FONT>       */<a name="line.188"></a>
<FONT color="green">189</FONT>      private boolean next() throws IOException, InterruptedException {<a name="line.189"></a>
<FONT color="green">190</FONT>        empty = !rr.nextKeyValue();<a name="line.190"></a>
<FONT color="green">191</FONT>        key = rr.getCurrentKey();<a name="line.191"></a>
<FONT color="green">192</FONT>        value = rr.getCurrentValue();<a name="line.192"></a>
<FONT color="green">193</FONT>        return !empty;<a name="line.193"></a>
<FONT color="green">194</FONT>      }<a name="line.194"></a>
<FONT color="green">195</FONT>    <a name="line.195"></a>
<FONT color="green">196</FONT>      /**<a name="line.196"></a>
<FONT color="green">197</FONT>       * Get current key <a name="line.197"></a>
<FONT color="green">198</FONT>       */<a name="line.198"></a>
<FONT color="green">199</FONT>      public K getCurrentKey() throws IOException, InterruptedException {<a name="line.199"></a>
<FONT color="green">200</FONT>        return rr.getCurrentKey();<a name="line.200"></a>
<FONT color="green">201</FONT>      }<a name="line.201"></a>
<FONT color="green">202</FONT>    <a name="line.202"></a>
<FONT color="green">203</FONT>      /**<a name="line.203"></a>
<FONT color="green">204</FONT>       * Get current value<a name="line.204"></a>
<FONT color="green">205</FONT>       */<a name="line.205"></a>
<FONT color="green">206</FONT>      public U getCurrentValue() throws IOException, InterruptedException {<a name="line.206"></a>
<FONT color="green">207</FONT>        return rr.getCurrentValue();<a name="line.207"></a>
<FONT color="green">208</FONT>      }<a name="line.208"></a>
<FONT color="green">209</FONT>    <a name="line.209"></a>
<FONT color="green">210</FONT>      /**<a name="line.210"></a>
<FONT color="green">211</FONT>       * Request progress from proxied RR.<a name="line.211"></a>
<FONT color="green">212</FONT>       */<a name="line.212"></a>
<FONT color="green">213</FONT>      public float getProgress() throws IOException, InterruptedException {<a name="line.213"></a>
<FONT color="green">214</FONT>        return rr.getProgress();<a name="line.214"></a>
<FONT color="green">215</FONT>      }<a name="line.215"></a>
<FONT color="green">216</FONT>    <a name="line.216"></a>
<FONT color="green">217</FONT>      /**<a name="line.217"></a>
<FONT color="green">218</FONT>       * Forward close request to proxied RR.<a name="line.218"></a>
<FONT color="green">219</FONT>       */<a name="line.219"></a>
<FONT color="green">220</FONT>      public void close() throws IOException {<a name="line.220"></a>
<FONT color="green">221</FONT>        rr.close();<a name="line.221"></a>
<FONT color="green">222</FONT>      }<a name="line.222"></a>
<FONT color="green">223</FONT>    <a name="line.223"></a>
<FONT color="green">224</FONT>      /**<a name="line.224"></a>
<FONT color="green">225</FONT>       * Implement Comparable contract (compare key at head of proxied RR<a name="line.225"></a>
<FONT color="green">226</FONT>       * with that of another).<a name="line.226"></a>
<FONT color="green">227</FONT>       */<a name="line.227"></a>
<FONT color="green">228</FONT>      public int compareTo(ComposableRecordReader&lt;K,?&gt; other) {<a name="line.228"></a>
<FONT color="green">229</FONT>        return cmp.compare(key(), other.key());<a name="line.229"></a>
<FONT color="green">230</FONT>      }<a name="line.230"></a>
<FONT color="green">231</FONT>    <a name="line.231"></a>
<FONT color="green">232</FONT>      /**<a name="line.232"></a>
<FONT color="green">233</FONT>       * Return true iff compareTo(other) retn true.<a name="line.233"></a>
<FONT color="green">234</FONT>       */<a name="line.234"></a>
<FONT color="green">235</FONT>      @SuppressWarnings("unchecked") // Explicit type check prior to cast<a name="line.235"></a>
<FONT color="green">236</FONT>      public boolean equals(Object other) {<a name="line.236"></a>
<FONT color="green">237</FONT>        return other instanceof ComposableRecordReader<a name="line.237"></a>
<FONT color="green">238</FONT>            &amp;&amp; 0 == compareTo((ComposableRecordReader)other);<a name="line.238"></a>
<FONT color="green">239</FONT>      }<a name="line.239"></a>
<FONT color="green">240</FONT>    <a name="line.240"></a>
<FONT color="green">241</FONT>      public int hashCode() {<a name="line.241"></a>
<FONT color="green">242</FONT>        assert false : "hashCode not designed";<a name="line.242"></a>
<FONT color="green">243</FONT>        return 42;<a name="line.243"></a>
<FONT color="green">244</FONT>      }<a name="line.244"></a>
<FONT color="green">245</FONT>    }<a name="line.245"></a>




























































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