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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.mapred;<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>    import java.util.regex.PatternSyntaxException;<a name="line.22"></a>
<FONT color="green">023</FONT>    <a name="line.23"></a>
<FONT color="green">024</FONT>    import org.apache.hadoop.classification.InterfaceAudience;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.apache.hadoop.classification.InterfaceStability;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.apache.hadoop.conf.Configuration;<a name="line.26"></a>
<FONT color="green">027</FONT>    import org.apache.hadoop.util.ReflectionUtils;<a name="line.27"></a>
<FONT color="green">028</FONT>    <a name="line.28"></a>
<FONT color="green">029</FONT>    /**<a name="line.29"></a>
<FONT color="green">030</FONT>     * A class that allows a map/red job to work on a sample of sequence files.<a name="line.30"></a>
<FONT color="green">031</FONT>     * The sample is decided by the filter class set by the job.<a name="line.31"></a>
<FONT color="green">032</FONT>     */<a name="line.32"></a>
<FONT color="green">033</FONT>    @InterfaceAudience.Public<a name="line.33"></a>
<FONT color="green">034</FONT>    @InterfaceStability.Stable<a name="line.34"></a>
<FONT color="green">035</FONT>    public class SequenceFileInputFilter&lt;K, V&gt;<a name="line.35"></a>
<FONT color="green">036</FONT>      extends SequenceFileInputFormat&lt;K, V&gt; {<a name="line.36"></a>
<FONT color="green">037</FONT>      <a name="line.37"></a>
<FONT color="green">038</FONT>      final private static String FILTER_CLASS = org.apache.hadoop.mapreduce.lib.<a name="line.38"></a>
<FONT color="green">039</FONT>          input.SequenceFileInputFilter.FILTER_CLASS;<a name="line.39"></a>
<FONT color="green">040</FONT>    <a name="line.40"></a>
<FONT color="green">041</FONT>      public SequenceFileInputFilter() {<a name="line.41"></a>
<FONT color="green">042</FONT>      }<a name="line.42"></a>
<FONT color="green">043</FONT>        <a name="line.43"></a>
<FONT color="green">044</FONT>      /** Create a record reader for the given split<a name="line.44"></a>
<FONT color="green">045</FONT>       * @param split file split<a name="line.45"></a>
<FONT color="green">046</FONT>       * @param job job configuration<a name="line.46"></a>
<FONT color="green">047</FONT>       * @param reporter reporter who sends report to task tracker<a name="line.47"></a>
<FONT color="green">048</FONT>       * @return RecordReader<a name="line.48"></a>
<FONT color="green">049</FONT>       */<a name="line.49"></a>
<FONT color="green">050</FONT>      public RecordReader&lt;K, V&gt; getRecordReader(InputSplit split,<a name="line.50"></a>
<FONT color="green">051</FONT>                                          JobConf job, Reporter reporter)<a name="line.51"></a>
<FONT color="green">052</FONT>        throws IOException {<a name="line.52"></a>
<FONT color="green">053</FONT>            <a name="line.53"></a>
<FONT color="green">054</FONT>        reporter.setStatus(split.toString());<a name="line.54"></a>
<FONT color="green">055</FONT>            <a name="line.55"></a>
<FONT color="green">056</FONT>        return new FilterRecordReader&lt;K, V&gt;(job, (FileSplit) split);<a name="line.56"></a>
<FONT color="green">057</FONT>      }<a name="line.57"></a>
<FONT color="green">058</FONT>    <a name="line.58"></a>
<FONT color="green">059</FONT>    <a name="line.59"></a>
<FONT color="green">060</FONT>      /** set the filter class<a name="line.60"></a>
<FONT color="green">061</FONT>       * <a name="line.61"></a>
<FONT color="green">062</FONT>       * @param conf application configuration<a name="line.62"></a>
<FONT color="green">063</FONT>       * @param filterClass filter class<a name="line.63"></a>
<FONT color="green">064</FONT>       */<a name="line.64"></a>
<FONT color="green">065</FONT>      public static void setFilterClass(Configuration conf, Class filterClass) {<a name="line.65"></a>
<FONT color="green">066</FONT>        conf.set(FILTER_CLASS, filterClass.getName());<a name="line.66"></a>
<FONT color="green">067</FONT>      }<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>             <a name="line.69"></a>
<FONT color="green">070</FONT>      /**<a name="line.70"></a>
<FONT color="green">071</FONT>       * filter interface<a name="line.71"></a>
<FONT color="green">072</FONT>       */<a name="line.72"></a>
<FONT color="green">073</FONT>      public interface Filter extends <a name="line.73"></a>
<FONT color="green">074</FONT>          org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.Filter {<a name="line.74"></a>
<FONT color="green">075</FONT>      }<a name="line.75"></a>
<FONT color="green">076</FONT>        <a name="line.76"></a>
<FONT color="green">077</FONT>      /**<a name="line.77"></a>
<FONT color="green">078</FONT>       * base class for Filters<a name="line.78"></a>
<FONT color="green">079</FONT>       */<a name="line.79"></a>
<FONT color="green">080</FONT>      public static abstract class FilterBase extends org.apache.hadoop.mapreduce.<a name="line.80"></a>
<FONT color="green">081</FONT>          lib.input.SequenceFileInputFilter.FilterBase<a name="line.81"></a>
<FONT color="green">082</FONT>          implements Filter {<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>      /** Records filter by matching key to regex<a name="line.85"></a>
<FONT color="green">086</FONT>       */<a name="line.86"></a>
<FONT color="green">087</FONT>      public static class RegexFilter extends FilterBase {<a name="line.87"></a>
<FONT color="green">088</FONT>        org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.<a name="line.88"></a>
<FONT color="green">089</FONT>          RegexFilter rf;<a name="line.89"></a>
<FONT color="green">090</FONT>        public static void setPattern(Configuration conf, String regex)<a name="line.90"></a>
<FONT color="green">091</FONT>            throws PatternSyntaxException {<a name="line.91"></a>
<FONT color="green">092</FONT>          org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.<a name="line.92"></a>
<FONT color="green">093</FONT>            RegexFilter.setPattern(conf, regex);<a name="line.93"></a>
<FONT color="green">094</FONT>        }<a name="line.94"></a>
<FONT color="green">095</FONT>            <a name="line.95"></a>
<FONT color="green">096</FONT>        public RegexFilter() { <a name="line.96"></a>
<FONT color="green">097</FONT>          rf = new org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.<a name="line.97"></a>
<FONT color="green">098</FONT>                 RegexFilter();<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>        /** configure the Filter by checking the configuration<a name="line.101"></a>
<FONT color="green">102</FONT>         */<a name="line.102"></a>
<FONT color="green">103</FONT>        public void setConf(Configuration conf) {<a name="line.103"></a>
<FONT color="green">104</FONT>          rf.setConf(conf);<a name="line.104"></a>
<FONT color="green">105</FONT>        }<a name="line.105"></a>
<FONT color="green">106</FONT>    <a name="line.106"></a>
<FONT color="green">107</FONT>    <a name="line.107"></a>
<FONT color="green">108</FONT>        /** Filtering method<a name="line.108"></a>
<FONT color="green">109</FONT>         * If key matches the regex, return true; otherwise return false<a name="line.109"></a>
<FONT color="green">110</FONT>         * @see org.apache.hadoop.mapred.SequenceFileInputFilter.Filter#accept(Object)<a name="line.110"></a>
<FONT color="green">111</FONT>         */<a name="line.111"></a>
<FONT color="green">112</FONT>        public boolean accept(Object key) {<a name="line.112"></a>
<FONT color="green">113</FONT>          return rf.accept(key);<a name="line.113"></a>
<FONT color="green">114</FONT>        }<a name="line.114"></a>
<FONT color="green">115</FONT>      }<a name="line.115"></a>
<FONT color="green">116</FONT>    <a name="line.116"></a>
<FONT color="green">117</FONT>      /** This class returns a percentage of records<a name="line.117"></a>
<FONT color="green">118</FONT>       * The percentage is determined by a filtering frequency &lt;i&gt;f&lt;/i&gt; using<a name="line.118"></a>
<FONT color="green">119</FONT>       * the criteria record# % f == 0.<a name="line.119"></a>
<FONT color="green">120</FONT>       * For example, if the frequency is 10, one out of 10 records is returned.<a name="line.120"></a>
<FONT color="green">121</FONT>       */<a name="line.121"></a>
<FONT color="green">122</FONT>      public static class PercentFilter extends FilterBase {<a name="line.122"></a>
<FONT color="green">123</FONT>        org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.<a name="line.123"></a>
<FONT color="green">124</FONT>                  PercentFilter pf;<a name="line.124"></a>
<FONT color="green">125</FONT>        /** set the frequency and stores it in conf<a name="line.125"></a>
<FONT color="green">126</FONT>         * @param conf configuration<a name="line.126"></a>
<FONT color="green">127</FONT>         * @param frequency filtering frequencey<a name="line.127"></a>
<FONT color="green">128</FONT>         */<a name="line.128"></a>
<FONT color="green">129</FONT>        public static void setFrequency(Configuration conf, int frequency) {<a name="line.129"></a>
<FONT color="green">130</FONT>           org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.<a name="line.130"></a>
<FONT color="green">131</FONT>                  PercentFilter.setFrequency(conf, frequency);<a name="line.131"></a>
<FONT color="green">132</FONT>        }<a name="line.132"></a>
<FONT color="green">133</FONT>                    <a name="line.133"></a>
<FONT color="green">134</FONT>        public PercentFilter() { <a name="line.134"></a>
<FONT color="green">135</FONT>          pf = new org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.<a name="line.135"></a>
<FONT color="green">136</FONT>            PercentFilter();<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>        /** configure the filter by checking the configuration<a name="line.139"></a>
<FONT color="green">140</FONT>         * <a name="line.140"></a>
<FONT color="green">141</FONT>         * @param conf configuration<a name="line.141"></a>
<FONT color="green">142</FONT>         */<a name="line.142"></a>
<FONT color="green">143</FONT>        public void setConf(Configuration conf) {<a name="line.143"></a>
<FONT color="green">144</FONT>          pf.setConf(conf);<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>        /** Filtering method<a name="line.147"></a>
<FONT color="green">148</FONT>         * If record# % frequency==0, return true; otherwise return false<a name="line.148"></a>
<FONT color="green">149</FONT>         * @see org.apache.hadoop.mapred.SequenceFileInputFilter.Filter#accept(Object)<a name="line.149"></a>
<FONT color="green">150</FONT>         */<a name="line.150"></a>
<FONT color="green">151</FONT>        public boolean accept(Object key) {<a name="line.151"></a>
<FONT color="green">152</FONT>          return pf.accept(key);<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>      /** This class returns a set of records by examing the MD5 digest of its<a name="line.156"></a>
<FONT color="green">157</FONT>       * key against a filtering frequency &lt;i&gt;f&lt;/i&gt;. The filtering criteria is<a name="line.157"></a>
<FONT color="green">158</FONT>       * MD5(key) % f == 0.<a name="line.158"></a>
<FONT color="green">159</FONT>       */<a name="line.159"></a>
<FONT color="green">160</FONT>      public static class MD5Filter extends FilterBase {<a name="line.160"></a>
<FONT color="green">161</FONT>        public static final int MD5_LEN = org.apache.hadoop.mapreduce.lib.<a name="line.161"></a>
<FONT color="green">162</FONT>          input.SequenceFileInputFilter.MD5Filter.MD5_LEN;<a name="line.162"></a>
<FONT color="green">163</FONT>        org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.MD5Filter mf;<a name="line.163"></a>
<FONT color="green">164</FONT>        /** set the filtering frequency in configuration<a name="line.164"></a>
<FONT color="green">165</FONT>         * <a name="line.165"></a>
<FONT color="green">166</FONT>         * @param conf configuration<a name="line.166"></a>
<FONT color="green">167</FONT>         * @param frequency filtering frequency<a name="line.167"></a>
<FONT color="green">168</FONT>         */<a name="line.168"></a>
<FONT color="green">169</FONT>        public static void setFrequency(Configuration conf, int frequency) {<a name="line.169"></a>
<FONT color="green">170</FONT>          org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.MD5Filter.<a name="line.170"></a>
<FONT color="green">171</FONT>            setFrequency(conf, frequency);<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>        public MD5Filter() { <a name="line.174"></a>
<FONT color="green">175</FONT>          mf = new org.apache.hadoop.mapreduce.lib.input.<a name="line.175"></a>
<FONT color="green">176</FONT>            SequenceFileInputFilter.MD5Filter();<a name="line.176"></a>
<FONT color="green">177</FONT>        }<a name="line.177"></a>
<FONT color="green">178</FONT>            <a name="line.178"></a>
<FONT color="green">179</FONT>        /** configure the filter according to configuration<a name="line.179"></a>
<FONT color="green">180</FONT>         * <a name="line.180"></a>
<FONT color="green">181</FONT>         * @param conf configuration<a name="line.181"></a>
<FONT color="green">182</FONT>         */<a name="line.182"></a>
<FONT color="green">183</FONT>        public void setConf(Configuration conf) {<a name="line.183"></a>
<FONT color="green">184</FONT>          mf.setConf(conf);<a name="line.184"></a>
<FONT color="green">185</FONT>        }<a name="line.185"></a>
<FONT color="green">186</FONT>    <a name="line.186"></a>
<FONT color="green">187</FONT>        /** Filtering method<a name="line.187"></a>
<FONT color="green">188</FONT>         * If MD5(key) % frequency==0, return true; otherwise return false<a name="line.188"></a>
<FONT color="green">189</FONT>         * @see org.apache.hadoop.mapred.SequenceFileInputFilter.Filter#accept(Object)<a name="line.189"></a>
<FONT color="green">190</FONT>         */<a name="line.190"></a>
<FONT color="green">191</FONT>        public boolean accept(Object key) {<a name="line.191"></a>
<FONT color="green">192</FONT>          return mf.accept(key);<a name="line.192"></a>
<FONT color="green">193</FONT>        }<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>      private static class FilterRecordReader&lt;K, V&gt;<a name="line.196"></a>
<FONT color="green">197</FONT>        extends SequenceFileRecordReader&lt;K, V&gt; {<a name="line.197"></a>
<FONT color="green">198</FONT>        <a name="line.198"></a>
<FONT color="green">199</FONT>        private Filter filter;<a name="line.199"></a>
<FONT color="green">200</FONT>            <a name="line.200"></a>
<FONT color="green">201</FONT>        public FilterRecordReader(Configuration conf, FileSplit split)<a name="line.201"></a>
<FONT color="green">202</FONT>          throws IOException {<a name="line.202"></a>
<FONT color="green">203</FONT>          super(conf, split);<a name="line.203"></a>
<FONT color="green">204</FONT>          // instantiate filter<a name="line.204"></a>
<FONT color="green">205</FONT>          filter = (Filter)ReflectionUtils.newInstance(<a name="line.205"></a>
<FONT color="green">206</FONT>                                                       conf.getClass(FILTER_CLASS, PercentFilter.class), <a name="line.206"></a>
<FONT color="green">207</FONT>                                                       conf);<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>        public synchronized boolean next(K key, V value) throws IOException {<a name="line.210"></a>
<FONT color="green">211</FONT>          while (next(key)) {<a name="line.211"></a>
<FONT color="green">212</FONT>            if (filter.accept(key)) {<a name="line.212"></a>
<FONT color="green">213</FONT>              getCurrentValue(value);<a name="line.213"></a>
<FONT color="green">214</FONT>              return true;<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>          return false;<a name="line.218"></a>
<FONT color="green">219</FONT>        }<a name="line.219"></a>
<FONT color="green">220</FONT>      }<a name="line.220"></a>
<FONT color="green">221</FONT>    }<a name="line.221"></a>




























































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