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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.output;<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.mapreduce.Job;<a name="line.26"></a>
<FONT color="green">027</FONT>    import org.apache.hadoop.mapreduce.JobContext;<a name="line.27"></a>
<FONT color="green">028</FONT>    import org.apache.hadoop.mapreduce.OutputCommitter;<a name="line.28"></a>
<FONT color="green">029</FONT>    import org.apache.hadoop.mapreduce.OutputFormat;<a name="line.29"></a>
<FONT color="green">030</FONT>    import org.apache.hadoop.mapreduce.RecordWriter;<a name="line.30"></a>
<FONT color="green">031</FONT>    import org.apache.hadoop.mapreduce.TaskAttemptContext;<a name="line.31"></a>
<FONT color="green">032</FONT>    import org.apache.hadoop.util.ReflectionUtils;<a name="line.32"></a>
<FONT color="green">033</FONT>    <a name="line.33"></a>
<FONT color="green">034</FONT>    /**<a name="line.34"></a>
<FONT color="green">035</FONT>     * A Convenience class that creates output lazily.  <a name="line.35"></a>
<FONT color="green">036</FONT>     */<a name="line.36"></a>
<FONT color="green">037</FONT>    @InterfaceAudience.Public<a name="line.37"></a>
<FONT color="green">038</FONT>    @InterfaceStability.Stable<a name="line.38"></a>
<FONT color="green">039</FONT>    public class LazyOutputFormat &lt;K,V&gt; extends FilterOutputFormat&lt;K, V&gt; {<a name="line.39"></a>
<FONT color="green">040</FONT>      public static String OUTPUT_FORMAT = <a name="line.40"></a>
<FONT color="green">041</FONT>        "mapreduce.output.lazyoutputformat.outputformat";<a name="line.41"></a>
<FONT color="green">042</FONT>      /**<a name="line.42"></a>
<FONT color="green">043</FONT>       * Set the underlying output format for LazyOutputFormat.<a name="line.43"></a>
<FONT color="green">044</FONT>       * @param job the {@link Job} to modify<a name="line.44"></a>
<FONT color="green">045</FONT>       * @param theClass the underlying class<a name="line.45"></a>
<FONT color="green">046</FONT>       */<a name="line.46"></a>
<FONT color="green">047</FONT>      @SuppressWarnings("unchecked")<a name="line.47"></a>
<FONT color="green">048</FONT>      public static void  setOutputFormatClass(Job job, <a name="line.48"></a>
<FONT color="green">049</FONT>                                         Class&lt;? extends OutputFormat&gt; theClass) {<a name="line.49"></a>
<FONT color="green">050</FONT>          job.setOutputFormatClass(LazyOutputFormat.class);<a name="line.50"></a>
<FONT color="green">051</FONT>          job.getConfiguration().setClass(OUTPUT_FORMAT, <a name="line.51"></a>
<FONT color="green">052</FONT>              theClass, OutputFormat.class);<a name="line.52"></a>
<FONT color="green">053</FONT>      }<a name="line.53"></a>
<FONT color="green">054</FONT>    <a name="line.54"></a>
<FONT color="green">055</FONT>      @SuppressWarnings("unchecked")<a name="line.55"></a>
<FONT color="green">056</FONT>      private void getBaseOutputFormat(Configuration conf) <a name="line.56"></a>
<FONT color="green">057</FONT>      throws IOException {<a name="line.57"></a>
<FONT color="green">058</FONT>        baseOut =  ((OutputFormat&lt;K, V&gt;) ReflectionUtils.newInstance(<a name="line.58"></a>
<FONT color="green">059</FONT>          conf.getClass(OUTPUT_FORMAT, null), conf));<a name="line.59"></a>
<FONT color="green">060</FONT>        if (baseOut == null) {<a name="line.60"></a>
<FONT color="green">061</FONT>          throw new IOException("Output Format not set for LazyOutputFormat");<a name="line.61"></a>
<FONT color="green">062</FONT>        }<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>      @Override<a name="line.65"></a>
<FONT color="green">066</FONT>      public RecordWriter&lt;K, V&gt; getRecordWriter(TaskAttemptContext context)<a name="line.66"></a>
<FONT color="green">067</FONT>      throws IOException, InterruptedException {<a name="line.67"></a>
<FONT color="green">068</FONT>        if (baseOut == null) {<a name="line.68"></a>
<FONT color="green">069</FONT>          getBaseOutputFormat(context.getConfiguration());<a name="line.69"></a>
<FONT color="green">070</FONT>        }<a name="line.70"></a>
<FONT color="green">071</FONT>        return new LazyRecordWriter&lt;K, V&gt;(baseOut, context);<a name="line.71"></a>
<FONT color="green">072</FONT>      }<a name="line.72"></a>
<FONT color="green">073</FONT>      <a name="line.73"></a>
<FONT color="green">074</FONT>      @Override<a name="line.74"></a>
<FONT color="green">075</FONT>      public void checkOutputSpecs(JobContext context) <a name="line.75"></a>
<FONT color="green">076</FONT>      throws IOException, InterruptedException {<a name="line.76"></a>
<FONT color="green">077</FONT>        if (baseOut == null) {<a name="line.77"></a>
<FONT color="green">078</FONT>          getBaseOutputFormat(context.getConfiguration());<a name="line.78"></a>
<FONT color="green">079</FONT>        }<a name="line.79"></a>
<FONT color="green">080</FONT>       super.checkOutputSpecs(context);<a name="line.80"></a>
<FONT color="green">081</FONT>      }<a name="line.81"></a>
<FONT color="green">082</FONT>      <a name="line.82"></a>
<FONT color="green">083</FONT>      @Override<a name="line.83"></a>
<FONT color="green">084</FONT>      public OutputCommitter getOutputCommitter(TaskAttemptContext context) <a name="line.84"></a>
<FONT color="green">085</FONT>      throws IOException, InterruptedException {<a name="line.85"></a>
<FONT color="green">086</FONT>        if (baseOut == null) {<a name="line.86"></a>
<FONT color="green">087</FONT>          getBaseOutputFormat(context.getConfiguration());<a name="line.87"></a>
<FONT color="green">088</FONT>        }<a name="line.88"></a>
<FONT color="green">089</FONT>        return super.getOutputCommitter(context);<a name="line.89"></a>
<FONT color="green">090</FONT>      }<a name="line.90"></a>
<FONT color="green">091</FONT>      <a name="line.91"></a>
<FONT color="green">092</FONT>      /**<a name="line.92"></a>
<FONT color="green">093</FONT>       * A convenience class to be used with LazyOutputFormat<a name="line.93"></a>
<FONT color="green">094</FONT>       */<a name="line.94"></a>
<FONT color="green">095</FONT>      private static class LazyRecordWriter&lt;K,V&gt; extends FilterRecordWriter&lt;K,V&gt; {<a name="line.95"></a>
<FONT color="green">096</FONT>    <a name="line.96"></a>
<FONT color="green">097</FONT>        final OutputFormat&lt;K,V&gt; outputFormat;<a name="line.97"></a>
<FONT color="green">098</FONT>        final TaskAttemptContext taskContext;<a name="line.98"></a>
<FONT color="green">099</FONT>    <a name="line.99"></a>
<FONT color="green">100</FONT>        public LazyRecordWriter(OutputFormat&lt;K,V&gt; out, <a name="line.100"></a>
<FONT color="green">101</FONT>                                TaskAttemptContext taskContext)<a name="line.101"></a>
<FONT color="green">102</FONT>        throws IOException, InterruptedException {<a name="line.102"></a>
<FONT color="green">103</FONT>          this.outputFormat = out;<a name="line.103"></a>
<FONT color="green">104</FONT>          this.taskContext = taskContext;<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>        @Override<a name="line.107"></a>
<FONT color="green">108</FONT>        public void write(K key, V value) throws IOException, InterruptedException {<a name="line.108"></a>
<FONT color="green">109</FONT>          if (rawWriter == null) {<a name="line.109"></a>
<FONT color="green">110</FONT>            rawWriter = outputFormat.getRecordWriter(taskContext);<a name="line.110"></a>
<FONT color="green">111</FONT>          }<a name="line.111"></a>
<FONT color="green">112</FONT>          rawWriter.write(key, value);<a name="line.112"></a>
<FONT color="green">113</FONT>        }<a name="line.113"></a>
<FONT color="green">114</FONT>    <a name="line.114"></a>
<FONT color="green">115</FONT>        @Override<a name="line.115"></a>
<FONT color="green">116</FONT>        public void close(TaskAttemptContext context) <a name="line.116"></a>
<FONT color="green">117</FONT>        throws IOException, InterruptedException {<a name="line.117"></a>
<FONT color="green">118</FONT>          if (rawWriter != null) {<a name="line.118"></a>
<FONT color="green">119</FONT>            rawWriter.close(context);<a name="line.119"></a>
<FONT color="green">120</FONT>          }<a name="line.120"></a>
<FONT color="green">121</FONT>        }<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>




























































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