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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.io.compress;<a name="line.19"></a>
<FONT color="green">020</FONT>    <a name="line.20"></a>
<FONT color="green">021</FONT>    import java.io.EOFException;<a name="line.21"></a>
<FONT color="green">022</FONT>    import java.io.IOException;<a name="line.22"></a>
<FONT color="green">023</FONT>    import java.io.InputStream;<a name="line.23"></a>
<FONT color="green">024</FONT>    <a name="line.24"></a>
<FONT color="green">025</FONT>    import org.apache.hadoop.classification.InterfaceAudience;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.apache.hadoop.classification.InterfaceStability;<a name="line.26"></a>
<FONT color="green">027</FONT>    <a name="line.27"></a>
<FONT color="green">028</FONT>    /**<a name="line.28"></a>
<FONT color="green">029</FONT>     * A {@link org.apache.hadoop.io.compress.DecompressorStream} which works<a name="line.29"></a>
<FONT color="green">030</FONT>     * with 'block-based' based compression algorithms, as opposed to <a name="line.30"></a>
<FONT color="green">031</FONT>     * 'stream-based' compression algorithms.<a name="line.31"></a>
<FONT color="green">032</FONT>     *  <a name="line.32"></a>
<FONT color="green">033</FONT>     */<a name="line.33"></a>
<FONT color="green">034</FONT>    @InterfaceAudience.Public<a name="line.34"></a>
<FONT color="green">035</FONT>    @InterfaceStability.Evolving<a name="line.35"></a>
<FONT color="green">036</FONT>    public class BlockDecompressorStream extends DecompressorStream {<a name="line.36"></a>
<FONT color="green">037</FONT>      private int originalBlockSize = 0;<a name="line.37"></a>
<FONT color="green">038</FONT>      private int noUncompressedBytes = 0;<a name="line.38"></a>
<FONT color="green">039</FONT>    <a name="line.39"></a>
<FONT color="green">040</FONT>      /**<a name="line.40"></a>
<FONT color="green">041</FONT>       * Create a {@link BlockDecompressorStream}.<a name="line.41"></a>
<FONT color="green">042</FONT>       * <a name="line.42"></a>
<FONT color="green">043</FONT>       * @param in input stream<a name="line.43"></a>
<FONT color="green">044</FONT>       * @param decompressor decompressor to use<a name="line.44"></a>
<FONT color="green">045</FONT>       * @param bufferSize size of buffer<a name="line.45"></a>
<FONT color="green">046</FONT>       * @throws IOException<a name="line.46"></a>
<FONT color="green">047</FONT>       */<a name="line.47"></a>
<FONT color="green">048</FONT>      public BlockDecompressorStream(InputStream in, Decompressor decompressor, <a name="line.48"></a>
<FONT color="green">049</FONT>                                     int bufferSize) throws IOException {<a name="line.49"></a>
<FONT color="green">050</FONT>        super(in, decompressor, bufferSize);<a name="line.50"></a>
<FONT color="green">051</FONT>      }<a name="line.51"></a>
<FONT color="green">052</FONT>    <a name="line.52"></a>
<FONT color="green">053</FONT>      /**<a name="line.53"></a>
<FONT color="green">054</FONT>       * Create a {@link BlockDecompressorStream}.<a name="line.54"></a>
<FONT color="green">055</FONT>       * <a name="line.55"></a>
<FONT color="green">056</FONT>       * @param in input stream<a name="line.56"></a>
<FONT color="green">057</FONT>       * @param decompressor decompressor to use<a name="line.57"></a>
<FONT color="green">058</FONT>       * @throws IOException<a name="line.58"></a>
<FONT color="green">059</FONT>       */<a name="line.59"></a>
<FONT color="green">060</FONT>      public BlockDecompressorStream(InputStream in, Decompressor decompressor) throws IOException {<a name="line.60"></a>
<FONT color="green">061</FONT>        super(in, decompressor);<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>      protected BlockDecompressorStream(InputStream in) throws IOException {<a name="line.64"></a>
<FONT color="green">065</FONT>        super(in);<a name="line.65"></a>
<FONT color="green">066</FONT>      }<a name="line.66"></a>
<FONT color="green">067</FONT>    <a name="line.67"></a>
<FONT color="green">068</FONT>      protected int decompress(byte[] b, int off, int len) throws IOException {<a name="line.68"></a>
<FONT color="green">069</FONT>        // Check if we are the beginning of a block<a name="line.69"></a>
<FONT color="green">070</FONT>        if (noUncompressedBytes == originalBlockSize) {<a name="line.70"></a>
<FONT color="green">071</FONT>          // Get original data size<a name="line.71"></a>
<FONT color="green">072</FONT>          try {<a name="line.72"></a>
<FONT color="green">073</FONT>            originalBlockSize =  rawReadInt();<a name="line.73"></a>
<FONT color="green">074</FONT>          } catch (IOException ioe) {<a name="line.74"></a>
<FONT color="green">075</FONT>            return -1;<a name="line.75"></a>
<FONT color="green">076</FONT>          }<a name="line.76"></a>
<FONT color="green">077</FONT>          noUncompressedBytes = 0;<a name="line.77"></a>
<FONT color="green">078</FONT>          // EOF if originalBlockSize is 0<a name="line.78"></a>
<FONT color="green">079</FONT>          // This will occur only when decompressing previous compressed empty file<a name="line.79"></a>
<FONT color="green">080</FONT>          if (originalBlockSize == 0) {<a name="line.80"></a>
<FONT color="green">081</FONT>            eof = true;<a name="line.81"></a>
<FONT color="green">082</FONT>            return -1;<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>    <a name="line.85"></a>
<FONT color="green">086</FONT>        int n = 0;<a name="line.86"></a>
<FONT color="green">087</FONT>        while ((n = decompressor.decompress(b, off, len)) == 0) {<a name="line.87"></a>
<FONT color="green">088</FONT>          if (decompressor.finished() || decompressor.needsDictionary()) {<a name="line.88"></a>
<FONT color="green">089</FONT>            if (noUncompressedBytes &gt;= originalBlockSize) {<a name="line.89"></a>
<FONT color="green">090</FONT>              eof = true;<a name="line.90"></a>
<FONT color="green">091</FONT>              return -1;<a name="line.91"></a>
<FONT color="green">092</FONT>            }<a name="line.92"></a>
<FONT color="green">093</FONT>          }<a name="line.93"></a>
<FONT color="green">094</FONT>          if (decompressor.needsInput()) {<a name="line.94"></a>
<FONT color="green">095</FONT>            int m = getCompressedData();<a name="line.95"></a>
<FONT color="green">096</FONT>            // Send the read data to the decompressor<a name="line.96"></a>
<FONT color="green">097</FONT>            decompressor.setInput(buffer, 0, m);<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>        // Note the no. of decompressed bytes read from 'current' block<a name="line.101"></a>
<FONT color="green">102</FONT>        noUncompressedBytes += n;<a name="line.102"></a>
<FONT color="green">103</FONT>    <a name="line.103"></a>
<FONT color="green">104</FONT>        return n;<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>      protected int getCompressedData() throws IOException {<a name="line.107"></a>
<FONT color="green">108</FONT>        checkStream();<a name="line.108"></a>
<FONT color="green">109</FONT>    <a name="line.109"></a>
<FONT color="green">110</FONT>        // Get the size of the compressed chunk (always non-negative)<a name="line.110"></a>
<FONT color="green">111</FONT>        int len = rawReadInt();<a name="line.111"></a>
<FONT color="green">112</FONT>    <a name="line.112"></a>
<FONT color="green">113</FONT>        // Read len bytes from underlying stream <a name="line.113"></a>
<FONT color="green">114</FONT>        if (len &gt; buffer.length) {<a name="line.114"></a>
<FONT color="green">115</FONT>          buffer = new byte[len];<a name="line.115"></a>
<FONT color="green">116</FONT>        }<a name="line.116"></a>
<FONT color="green">117</FONT>        int n = 0, off = 0;<a name="line.117"></a>
<FONT color="green">118</FONT>        while (n &lt; len) {<a name="line.118"></a>
<FONT color="green">119</FONT>          int count = in.read(buffer, off + n, len - n);<a name="line.119"></a>
<FONT color="green">120</FONT>          if (count &lt; 0) {<a name="line.120"></a>
<FONT color="green">121</FONT>            throw new EOFException("Unexpected end of block in input stream");<a name="line.121"></a>
<FONT color="green">122</FONT>          }<a name="line.122"></a>
<FONT color="green">123</FONT>          n += count;<a name="line.123"></a>
<FONT color="green">124</FONT>        }<a name="line.124"></a>
<FONT color="green">125</FONT>    <a name="line.125"></a>
<FONT color="green">126</FONT>        return len;<a name="line.126"></a>
<FONT color="green">127</FONT>      }<a name="line.127"></a>
<FONT color="green">128</FONT>    <a name="line.128"></a>
<FONT color="green">129</FONT>      public void resetState() throws IOException {<a name="line.129"></a>
<FONT color="green">130</FONT>        super.resetState();<a name="line.130"></a>
<FONT color="green">131</FONT>      }<a name="line.131"></a>
<FONT color="green">132</FONT>    <a name="line.132"></a>
<FONT color="green">133</FONT>      private int rawReadInt() throws IOException {<a name="line.133"></a>
<FONT color="green">134</FONT>        int b1 = in.read();<a name="line.134"></a>
<FONT color="green">135</FONT>        int b2 = in.read();<a name="line.135"></a>
<FONT color="green">136</FONT>        int b3 = in.read();<a name="line.136"></a>
<FONT color="green">137</FONT>        int b4 = in.read();<a name="line.137"></a>
<FONT color="green">138</FONT>        if ((b1 | b2 | b3 | b4) &lt; 0)<a name="line.138"></a>
<FONT color="green">139</FONT>          throw new EOFException();<a name="line.139"></a>
<FONT color="green">140</FONT>        return ((b1 &lt;&lt; 24) + (b2 &lt;&lt; 16) + (b3 &lt;&lt; 8) + (b4 &lt;&lt; 0));<a name="line.140"></a>
<FONT color="green">141</FONT>      }<a name="line.141"></a>
<FONT color="green">142</FONT>    }<a name="line.142"></a>




























































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