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From bode...@apache.org
Subject svn commit: r1006212 [13/16] - in /websites/production/commons/content/proper/commons-compress: ./ apidocs/org/apache/commons/compress/compressors/lz4/ apidocs/org/apache/commons/compress/compressors/snappy/ apidocs/src-html/org/apache/commons/compress...
Date Sat, 04 Feb 2017 16:19:38 GMT
Modified: websites/production/commons/content/proper/commons-compress/xref/org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html
==============================================================================
--- websites/production/commons/content/proper/commons-compress/xref/org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html (original)
+++ websites/production/commons/content/proper/commons-compress/xref/org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html Sat Feb  4 16:19:37 2017
@@ -32,439 +32,442 @@
 <a class="jxr_linenumber" name="L24" href="#L24">24</a>  <strong class="jxr_keyword">import</strong> java.util.Deque;
 <a class="jxr_linenumber" name="L25" href="#L25">25</a>  <strong class="jxr_keyword">import</strong> java.util.Iterator;
 <a class="jxr_linenumber" name="L26" href="#L26">26</a>  <strong class="jxr_keyword">import</strong> java.util.LinkedList;
-<a class="jxr_linenumber" name="L27" href="#L27">27</a>  <strong class="jxr_keyword">import</strong> java.util.List;
-<a class="jxr_linenumber" name="L28" href="#L28">28</a>  
-<a class="jxr_linenumber" name="L29" href="#L29">29</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.compressors.CompressorOutputStream;
-<a class="jxr_linenumber" name="L30" href="#L30">30</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.compressors.lz77support.LZ77Compressor;
-<a class="jxr_linenumber" name="L31" href="#L31">31</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.compressors.lz77support.Parameters;
-<a class="jxr_linenumber" name="L32" href="#L32">32</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.utils.ByteUtils;
-<a class="jxr_linenumber" name="L33" href="#L33">33</a>  
-<a class="jxr_linenumber" name="L34" href="#L34">34</a>  <em class="jxr_javadoccomment">/**</em>
-<a class="jxr_linenumber" name="L35" href="#L35">35</a>  <em class="jxr_javadoccomment"> * CompressorOutputStream for the LZ4 block format.</em>
-<a class="jxr_linenumber" name="L36" href="#L36">36</a>  <em class="jxr_javadoccomment"> *</em>
-<a class="jxr_linenumber" name="L37" href="#L37">37</a>  <em class="jxr_javadoccomment"> * @see &lt;a href="<a href="http://lz4.github.io/lz4/lz4_Block_format.html" target="alexandria_uri">http://lz4.github.io/lz4/lz4_Block_format.html</a>"&gt;LZ4 Block Format Description&lt;/a&gt;</em>
-<a class="jxr_linenumber" name="L38" href="#L38">38</a>  <em class="jxr_javadoccomment"> * @since 1.14</em>
-<a class="jxr_linenumber" name="L39" href="#L39">39</a>  <em class="jxr_javadoccomment"> * @NotThreadSafe</em>
-<a class="jxr_linenumber" name="L40" href="#L40">40</a>  <em class="jxr_javadoccomment"> */</em>
-<a class="jxr_linenumber" name="L41" href="#L41">41</a>  <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">BlockLZ4CompressorOutputStream</a> <strong class="jxr_keyword">extends</strong> <a href="../../../../../../org/apache/commons/compress/compressors/CompressorOutputStream.html">CompressorOutputStream</a> {
-<a class="jxr_linenumber" name="L42" href="#L42">42</a>  
-<a class="jxr_linenumber" name="L43" href="#L43">43</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> MIN_BACK_REFERENCE_LENGTH = 4;
-<a class="jxr_linenumber" name="L44" href="#L44">44</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> MIN_LENGTH_OF_LAST_LITERAL = 5;
-<a class="jxr_linenumber" name="L45" href="#L45">45</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> MIN_OFFSET_OF_LAST_BACK_REFERENCE = 12;
-<a class="jxr_linenumber" name="L46" href="#L46">46</a>  
-<a class="jxr_linenumber" name="L47" href="#L47">47</a>      <em class="jxr_comment">/*</em>
-<a class="jxr_linenumber" name="L48" href="#L48">48</a>  
-<a class="jxr_linenumber" name="L49" href="#L49">49</a>  <em class="jxr_comment">      The LZ4 block format has a few properties that make it less</em>
-<a class="jxr_linenumber" name="L50" href="#L50">50</a>  <em class="jxr_comment">      straight-forward than one would hope:</em>
-<a class="jxr_linenumber" name="L51" href="#L51">51</a>  
-<a class="jxr_linenumber" name="L52" href="#L52">52</a>  <em class="jxr_comment">      * literal blocks and back-references must come in pairs (except</em>
-<a class="jxr_linenumber" name="L53" href="#L53">53</a>  <em class="jxr_comment">        for the very last literal block), so consecutive literal</em>
-<a class="jxr_linenumber" name="L54" href="#L54">54</a>  <em class="jxr_comment">        blocks created by the compressor must be merged into a single</em>
-<a class="jxr_linenumber" name="L55" href="#L55">55</a>  <em class="jxr_comment">        block.</em>
-<a class="jxr_linenumber" name="L56" href="#L56">56</a>  
-<a class="jxr_linenumber" name="L57" href="#L57">57</a>  <em class="jxr_comment">      * the start of a literal/back-reference pair contains the length</em>
-<a class="jxr_linenumber" name="L58" href="#L58">58</a>  <em class="jxr_comment">        of the back-reference (at least some part of it) so we can't</em>
-<a class="jxr_linenumber" name="L59" href="#L59">59</a>  <em class="jxr_comment">        start writing the literal before we know how long the next</em>
-<a class="jxr_linenumber" name="L60" href="#L60">60</a>  <em class="jxr_comment">        back-reference is going to be.</em>
-<a class="jxr_linenumber" name="L61" href="#L61">61</a>  
-<a class="jxr_linenumber" name="L62" href="#L62">62</a>  <em class="jxr_comment">      * there are special rules for the final blocks</em>
-<a class="jxr_linenumber" name="L63" href="#L63">63</a>  
-<a class="jxr_linenumber" name="L64" href="#L64">64</a>  <em class="jxr_comment">        &gt; There are specific parsing rules to respect in order to remain</em>
-<a class="jxr_linenumber" name="L65" href="#L65">65</a>  <em class="jxr_comment">        &gt; compatible with assumptions made by the decoder :</em>
-<a class="jxr_linenumber" name="L66" href="#L66">66</a>  <em class="jxr_comment">        &gt;</em>
-<a class="jxr_linenumber" name="L67" href="#L67">67</a>  <em class="jxr_comment">        &gt;     1. The last 5 bytes are always literals</em>
-<a class="jxr_linenumber" name="L68" href="#L68">68</a>  <em class="jxr_comment">        &gt;</em>
-<a class="jxr_linenumber" name="L69" href="#L69">69</a>  <em class="jxr_comment">        &gt;     2. The last match must start at least 12 bytes before end of</em>
-<a class="jxr_linenumber" name="L70" href="#L70">70</a>  <em class="jxr_comment">        &gt;        block. Consequently, a block with less than 13 bytes cannot be</em>
-<a class="jxr_linenumber" name="L71" href="#L71">71</a>  <em class="jxr_comment">        &gt;        compressed.</em>
-<a class="jxr_linenumber" name="L72" href="#L72">72</a>  
-<a class="jxr_linenumber" name="L73" href="#L73">73</a>  <em class="jxr_comment">        which means any back-reference may need to get rewritten as a</em>
-<a class="jxr_linenumber" name="L74" href="#L74">74</a>  <em class="jxr_comment">        literal block unless we know the next block is at least of</em>
-<a class="jxr_linenumber" name="L75" href="#L75">75</a>  <em class="jxr_comment">        length 5 and the sum of this block's length and offset and the</em>
-<a class="jxr_linenumber" name="L76" href="#L76">76</a>  <em class="jxr_comment">        next block's length is at least twelve.</em>
-<a class="jxr_linenumber" name="L77" href="#L77">77</a>  
-<a class="jxr_linenumber" name="L78" href="#L78">78</a>  <em class="jxr_comment">    */</em>
-<a class="jxr_linenumber" name="L79" href="#L79">79</a>  
-<a class="jxr_linenumber" name="L80" href="#L80">80</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz77support/LZ77Compressor.html">LZ77Compressor</a> compressor;
-<a class="jxr_linenumber" name="L81" href="#L81">81</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> OutputStream os;
-<a class="jxr_linenumber" name="L82" href="#L82">82</a>  
-<a class="jxr_linenumber" name="L83" href="#L83">83</a>      <em class="jxr_comment">// used in one-arg write method</em>
-<a class="jxr_linenumber" name="L84" href="#L84">84</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> byte[] oneByte = <strong class="jxr_keyword">new</strong> byte[1];
-<a class="jxr_linenumber" name="L85" href="#L85">85</a>  
-<a class="jxr_linenumber" name="L86" href="#L86">86</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">boolean</strong> finished = false;
-<a class="jxr_linenumber" name="L87" href="#L87">87</a>  
-<a class="jxr_linenumber" name="L88" href="#L88">88</a>      <strong class="jxr_keyword">private</strong> Deque&lt;Pair&gt; pairs = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
-<a class="jxr_linenumber" name="L89" href="#L89">89</a>      <em class="jxr_comment">// keeps track of the last window-size bytes (64k) in order to be</em>
-<a class="jxr_linenumber" name="L90" href="#L90">90</a>      <em class="jxr_comment">// able to expand back-references when needed</em>
-<a class="jxr_linenumber" name="L91" href="#L91">91</a>      <strong class="jxr_keyword">private</strong> Deque&lt;byte[]&gt; expandedBlocks = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
-<a class="jxr_linenumber" name="L92" href="#L92">92</a>  
-<a class="jxr_linenumber" name="L93" href="#L93">93</a>      <em class="jxr_javadoccomment">/**</em>
-<a class="jxr_linenumber" name="L94" href="#L94">94</a>  <em class="jxr_javadoccomment">     * Creates a new LZ4 output stream.</em>
-<a class="jxr_linenumber" name="L95" href="#L95">95</a>  <em class="jxr_javadoccomment">     *</em>
-<a class="jxr_linenumber" name="L96" href="#L96">96</a>  <em class="jxr_javadoccomment">     * @param os</em>
-<a class="jxr_linenumber" name="L97" href="#L97">97</a>  <em class="jxr_javadoccomment">     *            An OutputStream to read compressed data from</em>
-<a class="jxr_linenumber" name="L98" href="#L98">98</a>  <em class="jxr_javadoccomment">     *</em>
-<a class="jxr_linenumber" name="L99" href="#L99">99</a>  <em class="jxr_javadoccomment">     * @throws IOException if reading fails</em>
-<a class="jxr_linenumber" name="L100" href="#L100">100</a> <em class="jxr_javadoccomment">     */</em>
-<a class="jxr_linenumber" name="L101" href="#L101">101</a>     <strong class="jxr_keyword">public</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">BlockLZ4CompressorOutputStream</a>(<strong class="jxr_keyword">final</strong> OutputStream os) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L102" href="#L102">102</a>         <strong class="jxr_keyword">this</strong>.os = os;
-<a class="jxr_linenumber" name="L103" href="#L103">103</a>         <strong class="jxr_keyword">int</strong> maxLen = BlockLZ4CompressorInputStream.WINDOW_SIZE - 1;
-<a class="jxr_linenumber" name="L104" href="#L104">104</a>         compressor = <strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz77support/LZ77Compressor.html">LZ77Compressor</a>(<strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz77support/Parameters.html">Parameters</a>(BlockLZ4CompressorInputStream.WINDOW_SIZE,
-<a class="jxr_linenumber" name="L105" href="#L105">105</a>             MIN_BACK_REFERENCE_LENGTH, maxLen, maxLen, maxLen),
-<a class="jxr_linenumber" name="L106" href="#L106">106</a>             <strong class="jxr_keyword">new</strong> LZ77Compressor.Callback() {
-<a class="jxr_linenumber" name="L107" href="#L107">107</a>                 <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> accept(LZ77Compressor.Block block) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L108" href="#L108">108</a>                     <em class="jxr_comment">//System.err.println(block);</em>
-<a class="jxr_linenumber" name="L109" href="#L109">109</a>                     <strong class="jxr_keyword">if</strong> (block instanceof LZ77Compressor.LiteralBlock) {
-<a class="jxr_linenumber" name="L110" href="#L110">110</a>                         addLiteralBlock((LZ77Compressor.LiteralBlock) block);
-<a class="jxr_linenumber" name="L111" href="#L111">111</a>                     } <strong class="jxr_keyword">else</strong> <strong class="jxr_keyword">if</strong> (block instanceof LZ77Compressor.BackReference) {
-<a class="jxr_linenumber" name="L112" href="#L112">112</a>                         addBackReference((LZ77Compressor.BackReference) block);
-<a class="jxr_linenumber" name="L113" href="#L113">113</a>                     } <strong class="jxr_keyword">else</strong> <strong class="jxr_keyword">if</strong> (block instanceof LZ77Compressor.EOD) {
-<a class="jxr_linenumber" name="L114" href="#L114">114</a>                         writeFinalLiteralBlock();
-<a class="jxr_linenumber" name="L115" href="#L115">115</a>                     }
-<a class="jxr_linenumber" name="L116" href="#L116">116</a>                 }
-<a class="jxr_linenumber" name="L117" href="#L117">117</a>             });
-<a class="jxr_linenumber" name="L118" href="#L118">118</a>     }
-<a class="jxr_linenumber" name="L119" href="#L119">119</a> 
-<a class="jxr_linenumber" name="L120" href="#L120">120</a>     @Override
-<a class="jxr_linenumber" name="L121" href="#L121">121</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> write(<strong class="jxr_keyword">int</strong> b) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L122" href="#L122">122</a>         oneByte[0] = (byte) (b &amp; 0xff);
-<a class="jxr_linenumber" name="L123" href="#L123">123</a>         write(oneByte);
-<a class="jxr_linenumber" name="L124" href="#L124">124</a>     }
-<a class="jxr_linenumber" name="L125" href="#L125">125</a> 
-<a class="jxr_linenumber" name="L126" href="#L126">126</a>     @Override
-<a class="jxr_linenumber" name="L127" href="#L127">127</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> write(byte[] data, <strong class="jxr_keyword">int</strong> off, <strong class="jxr_keyword">int</strong> len) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L128" href="#L128">128</a>         compressor.compress(data, off, len);
-<a class="jxr_linenumber" name="L129" href="#L129">129</a>     }
-<a class="jxr_linenumber" name="L130" href="#L130">130</a> 
-<a class="jxr_linenumber" name="L131" href="#L131">131</a>     @Override
-<a class="jxr_linenumber" name="L132" href="#L132">132</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> close() <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L133" href="#L133">133</a>         finish();
-<a class="jxr_linenumber" name="L134" href="#L134">134</a>         os.close();
-<a class="jxr_linenumber" name="L135" href="#L135">135</a>     }
-<a class="jxr_linenumber" name="L136" href="#L136">136</a> 
-<a class="jxr_linenumber" name="L137" href="#L137">137</a>     <em class="jxr_javadoccomment">/**</em>
-<a class="jxr_linenumber" name="L138" href="#L138">138</a> <em class="jxr_javadoccomment">     * Compresses all remaining data and writes it to the stream,</em>
-<a class="jxr_linenumber" name="L139" href="#L139">139</a> <em class="jxr_javadoccomment">     * doesn't close the underlying stream.</em>
-<a class="jxr_linenumber" name="L140" href="#L140">140</a> <em class="jxr_javadoccomment">     * @throws IOException if an error occurs</em>
-<a class="jxr_linenumber" name="L141" href="#L141">141</a> <em class="jxr_javadoccomment">     */</em>
-<a class="jxr_linenumber" name="L142" href="#L142">142</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> finish() <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L143" href="#L143">143</a>         <strong class="jxr_keyword">if</strong> (!finished) {
-<a class="jxr_linenumber" name="L144" href="#L144">144</a>             compressor.finish();
-<a class="jxr_linenumber" name="L145" href="#L145">145</a>             finished = <strong class="jxr_keyword">true</strong>;
-<a class="jxr_linenumber" name="L146" href="#L146">146</a>         }
-<a class="jxr_linenumber" name="L147" href="#L147">147</a>     }
-<a class="jxr_linenumber" name="L148" href="#L148">148</a> 
-<a class="jxr_linenumber" name="L149" href="#L149">149</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> addLiteralBlock(LZ77Compressor.LiteralBlock block) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L150" href="#L150">150</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> last = writeBlocksAndReturnUnfinishedPair(block.getLength());
-<a class="jxr_linenumber" name="L151" href="#L151">151</a>         recordLiteral(last.addLiteral(block));
-<a class="jxr_linenumber" name="L152" href="#L152">152</a>         clearUnusedBlocksAndPairs();
-<a class="jxr_linenumber" name="L153" href="#L153">153</a>     }
-<a class="jxr_linenumber" name="L154" href="#L154">154</a> 
-<a class="jxr_linenumber" name="L155" href="#L155">155</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> addBackReference(LZ77Compressor.BackReference block) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L156" href="#L156">156</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> last = writeBlocksAndReturnUnfinishedPair(block.getLength());
-<a class="jxr_linenumber" name="L157" href="#L157">157</a>         last.setBackReference(block);
-<a class="jxr_linenumber" name="L158" href="#L158">158</a>         recordBackReference(block);
-<a class="jxr_linenumber" name="L159" href="#L159">159</a>         clearUnusedBlocksAndPairs();
-<a class="jxr_linenumber" name="L160" href="#L160">160</a>     }
-<a class="jxr_linenumber" name="L161" href="#L161">161</a> 
-<a class="jxr_linenumber" name="L162" href="#L162">162</a>     <strong class="jxr_keyword">private</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> writeBlocksAndReturnUnfinishedPair(<strong class="jxr_keyword">int</strong> length) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L163" href="#L163">163</a>         writeWritablePairs(length);
-<a class="jxr_linenumber" name="L164" href="#L164">164</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> last = pairs.peekLast();
-<a class="jxr_linenumber" name="L165" href="#L165">165</a>         <strong class="jxr_keyword">if</strong> (last == <strong class="jxr_keyword">null</strong> || last.hasBackReference()) {
-<a class="jxr_linenumber" name="L166" href="#L166">166</a>             last = <strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a>();
-<a class="jxr_linenumber" name="L167" href="#L167">167</a>             pairs.addLast(last);
-<a class="jxr_linenumber" name="L168" href="#L168">168</a>         }
-<a class="jxr_linenumber" name="L169" href="#L169">169</a>         <strong class="jxr_keyword">return</strong> last;
-<a class="jxr_linenumber" name="L170" href="#L170">170</a>     }
-<a class="jxr_linenumber" name="L171" href="#L171">171</a> 
-<a class="jxr_linenumber" name="L172" href="#L172">172</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> recordLiteral(byte[] b) {
-<a class="jxr_linenumber" name="L173" href="#L173">173</a>         expandedBlocks.addFirst(b);
-<a class="jxr_linenumber" name="L174" href="#L174">174</a>     }
-<a class="jxr_linenumber" name="L175" href="#L175">175</a> 
-<a class="jxr_linenumber" name="L176" href="#L176">176</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> clearUnusedBlocksAndPairs() {
-<a class="jxr_linenumber" name="L177" href="#L177">177</a>         clearUnusedBlocks();
-<a class="jxr_linenumber" name="L178" href="#L178">178</a>         clearUnusedPairs();
-<a class="jxr_linenumber" name="L179" href="#L179">179</a>     }
-<a class="jxr_linenumber" name="L180" href="#L180">180</a> 
-<a class="jxr_linenumber" name="L181" href="#L181">181</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> clearUnusedBlocks() {
-<a class="jxr_linenumber" name="L182" href="#L182">182</a>         <strong class="jxr_keyword">int</strong> blockLengths = 0;
-<a class="jxr_linenumber" name="L183" href="#L183">183</a>         <strong class="jxr_keyword">int</strong> blocksToKeep = 0;
-<a class="jxr_linenumber" name="L184" href="#L184">184</a>         <strong class="jxr_keyword">for</strong> (byte[] b : expandedBlocks) {
-<a class="jxr_linenumber" name="L185" href="#L185">185</a>             blocksToKeep++;
-<a class="jxr_linenumber" name="L186" href="#L186">186</a>             blockLengths += b.length;
-<a class="jxr_linenumber" name="L187" href="#L187">187</a>             <strong class="jxr_keyword">if</strong> (blockLengths &gt;= BlockLZ4CompressorInputStream.WINDOW_SIZE) {
-<a class="jxr_linenumber" name="L188" href="#L188">188</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L189" href="#L189">189</a>             }
-<a class="jxr_linenumber" name="L190" href="#L190">190</a>         }
-<a class="jxr_linenumber" name="L191" href="#L191">191</a>         <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> size = expandedBlocks.size();
-<a class="jxr_linenumber" name="L192" href="#L192">192</a>         <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">int</strong> i = blocksToKeep; i &lt; size; i++) {
-<a class="jxr_linenumber" name="L193" href="#L193">193</a>             expandedBlocks.removeLast();
-<a class="jxr_linenumber" name="L194" href="#L194">194</a>         }
-<a class="jxr_linenumber" name="L195" href="#L195">195</a>     }
-<a class="jxr_linenumber" name="L196" href="#L196">196</a> 
-<a class="jxr_linenumber" name="L197" href="#L197">197</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> recordBackReference(LZ77Compressor.BackReference block) {
-<a class="jxr_linenumber" name="L198" href="#L198">198</a>         expandedBlocks.addFirst(expand(block.getOffset(), block.getLength()));
-<a class="jxr_linenumber" name="L199" href="#L199">199</a>     }
-<a class="jxr_linenumber" name="L200" href="#L200">200</a> 
-<a class="jxr_linenumber" name="L201" href="#L201">201</a>     <strong class="jxr_keyword">private</strong> byte[] expand(<strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> offset, <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> length) {
-<a class="jxr_linenumber" name="L202" href="#L202">202</a>         byte[] expanded = <strong class="jxr_keyword">new</strong> byte[length];
-<a class="jxr_linenumber" name="L203" href="#L203">203</a>         <strong class="jxr_keyword">if</strong> (offset == 1) { <em class="jxr_comment">// surprisingly common special case</em>
-<a class="jxr_linenumber" name="L204" href="#L204">204</a>             byte[] block = expandedBlocks.peekFirst();
-<a class="jxr_linenumber" name="L205" href="#L205">205</a>             byte b = block[block.length - 1];
-<a class="jxr_linenumber" name="L206" href="#L206">206</a>             <strong class="jxr_keyword">if</strong> (b != 0) { <em class="jxr_comment">// the fresh array contains 0s anyway</em>
-<a class="jxr_linenumber" name="L207" href="#L207">207</a>                 Arrays.fill(expanded, b);
-<a class="jxr_linenumber" name="L208" href="#L208">208</a>             }
-<a class="jxr_linenumber" name="L209" href="#L209">209</a>         } <strong class="jxr_keyword">else</strong> {
-<a class="jxr_linenumber" name="L210" href="#L210">210</a>             expandFromList(expanded, offset, length);
-<a class="jxr_linenumber" name="L211" href="#L211">211</a>         }
-<a class="jxr_linenumber" name="L212" href="#L212">212</a>         <strong class="jxr_keyword">return</strong> expanded;
-<a class="jxr_linenumber" name="L213" href="#L213">213</a>     }
-<a class="jxr_linenumber" name="L214" href="#L214">214</a> 
-<a class="jxr_linenumber" name="L215" href="#L215">215</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> expandFromList(<strong class="jxr_keyword">final</strong> byte[] expanded, <strong class="jxr_keyword">int</strong> offset, <strong class="jxr_keyword">int</strong> length) {
-<a class="jxr_linenumber" name="L216" href="#L216">216</a>         <strong class="jxr_keyword">int</strong> offsetRemaining = offset;
-<a class="jxr_linenumber" name="L217" href="#L217">217</a>         <strong class="jxr_keyword">int</strong> lengthRemaining = length;
-<a class="jxr_linenumber" name="L218" href="#L218">218</a>         <strong class="jxr_keyword">int</strong> writeOffset = 0;
-<a class="jxr_linenumber" name="L219" href="#L219">219</a>         <strong class="jxr_keyword">while</strong> (lengthRemaining &gt; 0) {
-<a class="jxr_linenumber" name="L220" href="#L220">220</a>             <em class="jxr_comment">// find block that contains offsetRemaining</em>
-<a class="jxr_linenumber" name="L221" href="#L221">221</a>             byte[] block = <strong class="jxr_keyword">null</strong>;
-<a class="jxr_linenumber" name="L222" href="#L222">222</a>             <strong class="jxr_keyword">int</strong> copyLen, copyOffset;
-<a class="jxr_linenumber" name="L223" href="#L223">223</a>             <strong class="jxr_keyword">if</strong> (offsetRemaining &gt; 0) {
-<a class="jxr_linenumber" name="L224" href="#L224">224</a>                 <strong class="jxr_keyword">int</strong> blockOffset = 0;
-<a class="jxr_linenumber" name="L225" href="#L225">225</a>                 <strong class="jxr_keyword">for</strong> (byte[] b : expandedBlocks) {
-<a class="jxr_linenumber" name="L226" href="#L226">226</a>                     <strong class="jxr_keyword">if</strong> (b.length + blockOffset &gt;= offsetRemaining) {
-<a class="jxr_linenumber" name="L227" href="#L227">227</a>                         block = b;
-<a class="jxr_linenumber" name="L228" href="#L228">228</a>                         <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L229" href="#L229">229</a>                     }
-<a class="jxr_linenumber" name="L230" href="#L230">230</a>                     blockOffset += b.length;
-<a class="jxr_linenumber" name="L231" href="#L231">231</a>                 }
-<a class="jxr_linenumber" name="L232" href="#L232">232</a>                 copyOffset = blockOffset + block.length - offsetRemaining;
-<a class="jxr_linenumber" name="L233" href="#L233">233</a>                 copyLen = Math.min(lengthRemaining, block.length - copyOffset);
-<a class="jxr_linenumber" name="L234" href="#L234">234</a>             } <strong class="jxr_keyword">else</strong> {
-<a class="jxr_linenumber" name="L235" href="#L235">235</a>                 <em class="jxr_comment">// offsetRemaining is negative and points into the expanded bytes</em>
-<a class="jxr_linenumber" name="L236" href="#L236">236</a>                 block = expanded;
-<a class="jxr_linenumber" name="L237" href="#L237">237</a>                 copyOffset = writeOffset  + offsetRemaining;
-<a class="jxr_linenumber" name="L238" href="#L238">238</a>                 copyLen = Math.min(lengthRemaining, writeOffset + offsetRemaining);
-<a class="jxr_linenumber" name="L239" href="#L239">239</a>             }
-<a class="jxr_linenumber" name="L240" href="#L240">240</a>             System.arraycopy(block, copyOffset, expanded, writeOffset, copyLen);
-<a class="jxr_linenumber" name="L241" href="#L241">241</a>             offsetRemaining -= copyLen;
-<a class="jxr_linenumber" name="L242" href="#L242">242</a>             lengthRemaining -= copyLen;
-<a class="jxr_linenumber" name="L243" href="#L243">243</a>             writeOffset += copyLen;
-<a class="jxr_linenumber" name="L244" href="#L244">244</a>         }
-<a class="jxr_linenumber" name="L245" href="#L245">245</a>     }
-<a class="jxr_linenumber" name="L246" href="#L246">246</a> 
-<a class="jxr_linenumber" name="L247" href="#L247">247</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> clearUnusedPairs() {
-<a class="jxr_linenumber" name="L248" href="#L248">248</a>         <strong class="jxr_keyword">int</strong> pairLengths = 0;
-<a class="jxr_linenumber" name="L249" href="#L249">249</a>         <strong class="jxr_keyword">int</strong> pairsToKeep = 0;
-<a class="jxr_linenumber" name="L250" href="#L250">250</a>         <strong class="jxr_keyword">for</strong> (Iterator&lt;Pair&gt; it = pairs.descendingIterator(); it.hasNext(); ) {
-<a class="jxr_linenumber" name="L251" href="#L251">251</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = it.next();
-<a class="jxr_linenumber" name="L252" href="#L252">252</a>             pairsToKeep++;
-<a class="jxr_linenumber" name="L253" href="#L253">253</a>             pairLengths += p.length();
-<a class="jxr_linenumber" name="L254" href="#L254">254</a>             <strong class="jxr_keyword">if</strong> (pairLengths &gt;= BlockLZ4CompressorInputStream.WINDOW_SIZE) {
-<a class="jxr_linenumber" name="L255" href="#L255">255</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L256" href="#L256">256</a>             }
-<a class="jxr_linenumber" name="L257" href="#L257">257</a>         }
-<a class="jxr_linenumber" name="L258" href="#L258">258</a>         <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> size = pairs.size();
-<a class="jxr_linenumber" name="L259" href="#L259">259</a>         <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">int</strong> i = pairsToKeep; i &lt; size; i++) {
-<a class="jxr_linenumber" name="L260" href="#L260">260</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = pairs.peekFirst();
-<a class="jxr_linenumber" name="L261" href="#L261">261</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
-<a class="jxr_linenumber" name="L262" href="#L262">262</a>                 pairs.removeFirst();
-<a class="jxr_linenumber" name="L263" href="#L263">263</a>             } <strong class="jxr_keyword">else</strong> {
-<a class="jxr_linenumber" name="L264" href="#L264">264</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L265" href="#L265">265</a>             }
-<a class="jxr_linenumber" name="L266" href="#L266">266</a>         }
-<a class="jxr_linenumber" name="L267" href="#L267">267</a>     }
-<a class="jxr_linenumber" name="L268" href="#L268">268</a> 
-<a class="jxr_linenumber" name="L269" href="#L269">269</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> writeFinalLiteralBlock() <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L270" href="#L270">270</a>         rewriteLastPairs();
-<a class="jxr_linenumber" name="L271" href="#L271">271</a>         <strong class="jxr_keyword">for</strong> (Pair p : pairs) {
-<a class="jxr_linenumber" name="L272" href="#L272">272</a>             <strong class="jxr_keyword">if</strong> (!p.hasBeenWritten()) {
-<a class="jxr_linenumber" name="L273" href="#L273">273</a>                 p.writeTo(os);
-<a class="jxr_linenumber" name="L274" href="#L274">274</a>             }
-<a class="jxr_linenumber" name="L275" href="#L275">275</a>         }
-<a class="jxr_linenumber" name="L276" href="#L276">276</a>         pairs.clear();
-<a class="jxr_linenumber" name="L277" href="#L277">277</a>     }
-<a class="jxr_linenumber" name="L278" href="#L278">278</a> 
-<a class="jxr_linenumber" name="L279" href="#L279">279</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> writeWritablePairs(<strong class="jxr_keyword">int</strong> lengthOfBlocksAfterLastPair) <strong class="jxr_keyword">throws</strong> IOException {
-<a class="jxr_linenumber" name="L280" href="#L280">280</a>         <strong class="jxr_keyword">int</strong> unwrittenLength = lengthOfBlocksAfterLastPair;
-<a class="jxr_linenumber" name="L281" href="#L281">281</a>         <strong class="jxr_keyword">for</strong> (Iterator&lt;Pair&gt; it = pairs.descendingIterator(); it.hasNext(); ) {
-<a class="jxr_linenumber" name="L282" href="#L282">282</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = it.next();
-<a class="jxr_linenumber" name="L283" href="#L283">283</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
-<a class="jxr_linenumber" name="L284" href="#L284">284</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L285" href="#L285">285</a>             }
-<a class="jxr_linenumber" name="L286" href="#L286">286</a>             unwrittenLength += p.length();
-<a class="jxr_linenumber" name="L287" href="#L287">287</a>         }
-<a class="jxr_linenumber" name="L288" href="#L288">288</a>         <strong class="jxr_keyword">for</strong> (Pair p : pairs) {
-<a class="jxr_linenumber" name="L289" href="#L289">289</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
-<a class="jxr_linenumber" name="L290" href="#L290">290</a>                 <strong class="jxr_keyword">continue</strong>;
-<a class="jxr_linenumber" name="L291" href="#L291">291</a>             }
-<a class="jxr_linenumber" name="L292" href="#L292">292</a>             unwrittenLength -= p.length();
-<a class="jxr_linenumber" name="L293" href="#L293">293</a>             <strong class="jxr_keyword">if</strong> (p.canBeWritten(unwrittenLength)) {
-<a class="jxr_linenumber" name="L294" href="#L294">294</a>                 p.writeTo(os);
-<a class="jxr_linenumber" name="L295" href="#L295">295</a>             } <strong class="jxr_keyword">else</strong> {
-<a class="jxr_linenumber" name="L296" href="#L296">296</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L297" href="#L297">297</a>             }
-<a class="jxr_linenumber" name="L298" href="#L298">298</a>         }
-<a class="jxr_linenumber" name="L299" href="#L299">299</a>     }
-<a class="jxr_linenumber" name="L300" href="#L300">300</a> 
-<a class="jxr_linenumber" name="L301" href="#L301">301</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> rewriteLastPairs() {
-<a class="jxr_linenumber" name="L302" href="#L302">302</a>         LinkedList&lt;Pair&gt; lastPairs = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
-<a class="jxr_linenumber" name="L303" href="#L303">303</a>         LinkedList&lt;Integer&gt; pairLength = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
-<a class="jxr_linenumber" name="L304" href="#L304">304</a>         <strong class="jxr_keyword">int</strong> offset = 0;
-<a class="jxr_linenumber" name="L305" href="#L305">305</a>         <strong class="jxr_keyword">for</strong> (Iterator&lt;Pair&gt; it = pairs.descendingIterator(); it.hasNext(); ) {
-<a class="jxr_linenumber" name="L306" href="#L306">306</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = it.next();
-<a class="jxr_linenumber" name="L307" href="#L307">307</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
-<a class="jxr_linenumber" name="L308" href="#L308">308</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L309" href="#L309">309</a>             }
-<a class="jxr_linenumber" name="L310" href="#L310">310</a>             <strong class="jxr_keyword">int</strong> len = p.length();
-<a class="jxr_linenumber" name="L311" href="#L311">311</a>             pairLength.addFirst(len);
-<a class="jxr_linenumber" name="L312" href="#L312">312</a>             lastPairs.addFirst(p);
-<a class="jxr_linenumber" name="L313" href="#L313">313</a>             offset += len;
-<a class="jxr_linenumber" name="L314" href="#L314">314</a>             <strong class="jxr_keyword">if</strong> (offset &gt;= MIN_OFFSET_OF_LAST_BACK_REFERENCE) {
-<a class="jxr_linenumber" name="L315" href="#L315">315</a>                 <strong class="jxr_keyword">break</strong>;
-<a class="jxr_linenumber" name="L316" href="#L316">316</a>             }
-<a class="jxr_linenumber" name="L317" href="#L317">317</a>         }
-<a class="jxr_linenumber" name="L318" href="#L318">318</a>         <strong class="jxr_keyword">for</strong> (Pair p : lastPairs) {
-<a class="jxr_linenumber" name="L319" href="#L319">319</a>             pairs.remove(p);
+<a class="jxr_linenumber" name="L27" href="#L27">27</a>  
+<a class="jxr_linenumber" name="L28" href="#L28">28</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.compressors.CompressorOutputStream;
+<a class="jxr_linenumber" name="L29" href="#L29">29</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.compressors.lz77support.LZ77Compressor;
+<a class="jxr_linenumber" name="L30" href="#L30">30</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.compressors.lz77support.Parameters;
+<a class="jxr_linenumber" name="L31" href="#L31">31</a>  <strong class="jxr_keyword">import</strong> org.apache.commons.compress.utils.ByteUtils;
+<a class="jxr_linenumber" name="L32" href="#L32">32</a>  
+<a class="jxr_linenumber" name="L33" href="#L33">33</a>  <em class="jxr_javadoccomment">/**</em>
+<a class="jxr_linenumber" name="L34" href="#L34">34</a>  <em class="jxr_javadoccomment"> * CompressorOutputStream for the LZ4 block format.</em>
+<a class="jxr_linenumber" name="L35" href="#L35">35</a>  <em class="jxr_javadoccomment"> *</em>
+<a class="jxr_linenumber" name="L36" href="#L36">36</a>  <em class="jxr_javadoccomment"> * @see &lt;a href="<a href="http://lz4.github.io/lz4/lz4_Block_format.html" target="alexandria_uri">http://lz4.github.io/lz4/lz4_Block_format.html</a>"&gt;LZ4 Block Format Description&lt;/a&gt;</em>
+<a class="jxr_linenumber" name="L37" href="#L37">37</a>  <em class="jxr_javadoccomment"> * @since 1.14</em>
+<a class="jxr_linenumber" name="L38" href="#L38">38</a>  <em class="jxr_javadoccomment"> * @NotThreadSafe</em>
+<a class="jxr_linenumber" name="L39" href="#L39">39</a>  <em class="jxr_javadoccomment"> */</em>
+<a class="jxr_linenumber" name="L40" href="#L40">40</a>  <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">BlockLZ4CompressorOutputStream</a> <strong class="jxr_keyword">extends</strong> <a href="../../../../../../org/apache/commons/compress/compressors/CompressorOutputStream.html">CompressorOutputStream</a> {
+<a class="jxr_linenumber" name="L41" href="#L41">41</a>  
+<a class="jxr_linenumber" name="L42" href="#L42">42</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> MIN_BACK_REFERENCE_LENGTH = 4;
+<a class="jxr_linenumber" name="L43" href="#L43">43</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> MIN_LENGTH_OF_LAST_LITERAL = 5;
+<a class="jxr_linenumber" name="L44" href="#L44">44</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> MIN_OFFSET_OF_LAST_BACK_REFERENCE = 12;
+<a class="jxr_linenumber" name="L45" href="#L45">45</a>  
+<a class="jxr_linenumber" name="L46" href="#L46">46</a>      <em class="jxr_comment">/*</em>
+<a class="jxr_linenumber" name="L47" href="#L47">47</a>  
+<a class="jxr_linenumber" name="L48" href="#L48">48</a>  <em class="jxr_comment">      The LZ4 block format has a few properties that make it less</em>
+<a class="jxr_linenumber" name="L49" href="#L49">49</a>  <em class="jxr_comment">      straight-forward than one would hope:</em>
+<a class="jxr_linenumber" name="L50" href="#L50">50</a>  
+<a class="jxr_linenumber" name="L51" href="#L51">51</a>  <em class="jxr_comment">      * literal blocks and back-references must come in pairs (except</em>
+<a class="jxr_linenumber" name="L52" href="#L52">52</a>  <em class="jxr_comment">        for the very last literal block), so consecutive literal</em>
+<a class="jxr_linenumber" name="L53" href="#L53">53</a>  <em class="jxr_comment">        blocks created by the compressor must be merged into a single</em>
+<a class="jxr_linenumber" name="L54" href="#L54">54</a>  <em class="jxr_comment">        block.</em>
+<a class="jxr_linenumber" name="L55" href="#L55">55</a>  
+<a class="jxr_linenumber" name="L56" href="#L56">56</a>  <em class="jxr_comment">      * the start of a literal/back-reference pair contains the length</em>
+<a class="jxr_linenumber" name="L57" href="#L57">57</a>  <em class="jxr_comment">        of the back-reference (at least some part of it) so we can't</em>
+<a class="jxr_linenumber" name="L58" href="#L58">58</a>  <em class="jxr_comment">        start writing the literal before we know how long the next</em>
+<a class="jxr_linenumber" name="L59" href="#L59">59</a>  <em class="jxr_comment">        back-reference is going to be.</em>
+<a class="jxr_linenumber" name="L60" href="#L60">60</a>  
+<a class="jxr_linenumber" name="L61" href="#L61">61</a>  <em class="jxr_comment">      * there are special rules for the final blocks</em>
+<a class="jxr_linenumber" name="L62" href="#L62">62</a>  
+<a class="jxr_linenumber" name="L63" href="#L63">63</a>  <em class="jxr_comment">        &gt; There are specific parsing rules to respect in order to remain</em>
+<a class="jxr_linenumber" name="L64" href="#L64">64</a>  <em class="jxr_comment">        &gt; compatible with assumptions made by the decoder :</em>
+<a class="jxr_linenumber" name="L65" href="#L65">65</a>  <em class="jxr_comment">        &gt;</em>
+<a class="jxr_linenumber" name="L66" href="#L66">66</a>  <em class="jxr_comment">        &gt;     1. The last 5 bytes are always literals</em>
+<a class="jxr_linenumber" name="L67" href="#L67">67</a>  <em class="jxr_comment">        &gt;</em>
+<a class="jxr_linenumber" name="L68" href="#L68">68</a>  <em class="jxr_comment">        &gt;     2. The last match must start at least 12 bytes before end of</em>
+<a class="jxr_linenumber" name="L69" href="#L69">69</a>  <em class="jxr_comment">        &gt;        block. Consequently, a block with less than 13 bytes cannot be</em>
+<a class="jxr_linenumber" name="L70" href="#L70">70</a>  <em class="jxr_comment">        &gt;        compressed.</em>
+<a class="jxr_linenumber" name="L71" href="#L71">71</a>  
+<a class="jxr_linenumber" name="L72" href="#L72">72</a>  <em class="jxr_comment">        which means any back-reference may need to get rewritten as a</em>
+<a class="jxr_linenumber" name="L73" href="#L73">73</a>  <em class="jxr_comment">        literal block unless we know the next block is at least of</em>
+<a class="jxr_linenumber" name="L74" href="#L74">74</a>  <em class="jxr_comment">        length 5 and the sum of this block's length and offset and the</em>
+<a class="jxr_linenumber" name="L75" href="#L75">75</a>  <em class="jxr_comment">        next block's length is at least twelve.</em>
+<a class="jxr_linenumber" name="L76" href="#L76">76</a>  
+<a class="jxr_linenumber" name="L77" href="#L77">77</a>  <em class="jxr_comment">    */</em>
+<a class="jxr_linenumber" name="L78" href="#L78">78</a>  
+<a class="jxr_linenumber" name="L79" href="#L79">79</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz77support/LZ77Compressor.html">LZ77Compressor</a> compressor;
+<a class="jxr_linenumber" name="L80" href="#L80">80</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> OutputStream os;
+<a class="jxr_linenumber" name="L81" href="#L81">81</a>  
+<a class="jxr_linenumber" name="L82" href="#L82">82</a>      <em class="jxr_comment">// used in one-arg write method</em>
+<a class="jxr_linenumber" name="L83" href="#L83">83</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> byte[] oneByte = <strong class="jxr_keyword">new</strong> byte[1];
+<a class="jxr_linenumber" name="L84" href="#L84">84</a>  
+<a class="jxr_linenumber" name="L85" href="#L85">85</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">boolean</strong> finished = false;
+<a class="jxr_linenumber" name="L86" href="#L86">86</a>  
+<a class="jxr_linenumber" name="L87" href="#L87">87</a>      <strong class="jxr_keyword">private</strong> Deque&lt;Pair&gt; pairs = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
+<a class="jxr_linenumber" name="L88" href="#L88">88</a>      <em class="jxr_comment">// keeps track of the last window-size bytes (64k) in order to be</em>
+<a class="jxr_linenumber" name="L89" href="#L89">89</a>      <em class="jxr_comment">// able to expand back-references when needed</em>
+<a class="jxr_linenumber" name="L90" href="#L90">90</a>      <strong class="jxr_keyword">private</strong> Deque&lt;byte[]&gt; expandedBlocks = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
+<a class="jxr_linenumber" name="L91" href="#L91">91</a>  
+<a class="jxr_linenumber" name="L92" href="#L92">92</a>      <em class="jxr_javadoccomment">/**</em>
+<a class="jxr_linenumber" name="L93" href="#L93">93</a>  <em class="jxr_javadoccomment">     * Creates a new LZ4 output stream.</em>
+<a class="jxr_linenumber" name="L94" href="#L94">94</a>  <em class="jxr_javadoccomment">     *</em>
+<a class="jxr_linenumber" name="L95" href="#L95">95</a>  <em class="jxr_javadoccomment">     * @param os</em>
+<a class="jxr_linenumber" name="L96" href="#L96">96</a>  <em class="jxr_javadoccomment">     *            An OutputStream to read compressed data from</em>
+<a class="jxr_linenumber" name="L97" href="#L97">97</a>  <em class="jxr_javadoccomment">     *</em>
+<a class="jxr_linenumber" name="L98" href="#L98">98</a>  <em class="jxr_javadoccomment">     * @throws IOException if reading fails</em>
+<a class="jxr_linenumber" name="L99" href="#L99">99</a>  <em class="jxr_javadoccomment">     */</em>
+<a class="jxr_linenumber" name="L100" href="#L100">100</a>     <strong class="jxr_keyword">public</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">BlockLZ4CompressorOutputStream</a>(<strong class="jxr_keyword">final</strong> OutputStream os) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L101" href="#L101">101</a>         <strong class="jxr_keyword">this</strong>.os = os;
+<a class="jxr_linenumber" name="L102" href="#L102">102</a>         <strong class="jxr_keyword">int</strong> maxLen = BlockLZ4CompressorInputStream.WINDOW_SIZE - 1;
+<a class="jxr_linenumber" name="L103" href="#L103">103</a>         compressor = <strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz77support/LZ77Compressor.html">LZ77Compressor</a>(<strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz77support/Parameters.html">Parameters</a>(BlockLZ4CompressorInputStream.WINDOW_SIZE,
+<a class="jxr_linenumber" name="L104" href="#L104">104</a>             MIN_BACK_REFERENCE_LENGTH, maxLen, maxLen, maxLen),
+<a class="jxr_linenumber" name="L105" href="#L105">105</a>             <strong class="jxr_keyword">new</strong> LZ77Compressor.Callback() {
+<a class="jxr_linenumber" name="L106" href="#L106">106</a>                 <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> accept(LZ77Compressor.Block block) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L107" href="#L107">107</a>                     <em class="jxr_comment">//System.err.println(block);</em>
+<a class="jxr_linenumber" name="L108" href="#L108">108</a>                     <strong class="jxr_keyword">if</strong> (block instanceof LZ77Compressor.LiteralBlock) {
+<a class="jxr_linenumber" name="L109" href="#L109">109</a>                         addLiteralBlock((LZ77Compressor.LiteralBlock) block);
+<a class="jxr_linenumber" name="L110" href="#L110">110</a>                     } <strong class="jxr_keyword">else</strong> <strong class="jxr_keyword">if</strong> (block instanceof LZ77Compressor.BackReference) {
+<a class="jxr_linenumber" name="L111" href="#L111">111</a>                         addBackReference((LZ77Compressor.BackReference) block);
+<a class="jxr_linenumber" name="L112" href="#L112">112</a>                     } <strong class="jxr_keyword">else</strong> <strong class="jxr_keyword">if</strong> (block instanceof LZ77Compressor.EOD) {
+<a class="jxr_linenumber" name="L113" href="#L113">113</a>                         writeFinalLiteralBlock();
+<a class="jxr_linenumber" name="L114" href="#L114">114</a>                     }
+<a class="jxr_linenumber" name="L115" href="#L115">115</a>                 }
+<a class="jxr_linenumber" name="L116" href="#L116">116</a>             });
+<a class="jxr_linenumber" name="L117" href="#L117">117</a>     }
+<a class="jxr_linenumber" name="L118" href="#L118">118</a> 
+<a class="jxr_linenumber" name="L119" href="#L119">119</a>     @Override
+<a class="jxr_linenumber" name="L120" href="#L120">120</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> write(<strong class="jxr_keyword">int</strong> b) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L121" href="#L121">121</a>         oneByte[0] = (byte) (b &amp; 0xff);
+<a class="jxr_linenumber" name="L122" href="#L122">122</a>         write(oneByte);
+<a class="jxr_linenumber" name="L123" href="#L123">123</a>     }
+<a class="jxr_linenumber" name="L124" href="#L124">124</a> 
+<a class="jxr_linenumber" name="L125" href="#L125">125</a>     @Override
+<a class="jxr_linenumber" name="L126" href="#L126">126</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> write(byte[] data, <strong class="jxr_keyword">int</strong> off, <strong class="jxr_keyword">int</strong> len) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L127" href="#L127">127</a>         compressor.compress(data, off, len);
+<a class="jxr_linenumber" name="L128" href="#L128">128</a>     }
+<a class="jxr_linenumber" name="L129" href="#L129">129</a> 
+<a class="jxr_linenumber" name="L130" href="#L130">130</a>     @Override
+<a class="jxr_linenumber" name="L131" href="#L131">131</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> close() <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L132" href="#L132">132</a>         finish();
+<a class="jxr_linenumber" name="L133" href="#L133">133</a>         os.close();
+<a class="jxr_linenumber" name="L134" href="#L134">134</a>     }
+<a class="jxr_linenumber" name="L135" href="#L135">135</a> 
+<a class="jxr_linenumber" name="L136" href="#L136">136</a>     <em class="jxr_javadoccomment">/**</em>
+<a class="jxr_linenumber" name="L137" href="#L137">137</a> <em class="jxr_javadoccomment">     * Compresses all remaining data and writes it to the stream,</em>
+<a class="jxr_linenumber" name="L138" href="#L138">138</a> <em class="jxr_javadoccomment">     * doesn't close the underlying stream.</em>
+<a class="jxr_linenumber" name="L139" href="#L139">139</a> <em class="jxr_javadoccomment">     * @throws IOException if an error occurs</em>
+<a class="jxr_linenumber" name="L140" href="#L140">140</a> <em class="jxr_javadoccomment">     */</em>
+<a class="jxr_linenumber" name="L141" href="#L141">141</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> finish() <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L142" href="#L142">142</a>         <strong class="jxr_keyword">if</strong> (!finished) {
+<a class="jxr_linenumber" name="L143" href="#L143">143</a>             compressor.finish();
+<a class="jxr_linenumber" name="L144" href="#L144">144</a>             finished = <strong class="jxr_keyword">true</strong>;
+<a class="jxr_linenumber" name="L145" href="#L145">145</a>         }
+<a class="jxr_linenumber" name="L146" href="#L146">146</a>     }
+<a class="jxr_linenumber" name="L147" href="#L147">147</a> 
+<a class="jxr_linenumber" name="L148" href="#L148">148</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> addLiteralBlock(LZ77Compressor.LiteralBlock block) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L149" href="#L149">149</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> last = writeBlocksAndReturnUnfinishedPair(block.getLength());
+<a class="jxr_linenumber" name="L150" href="#L150">150</a>         recordLiteral(last.addLiteral(block));
+<a class="jxr_linenumber" name="L151" href="#L151">151</a>         clearUnusedBlocksAndPairs();
+<a class="jxr_linenumber" name="L152" href="#L152">152</a>     }
+<a class="jxr_linenumber" name="L153" href="#L153">153</a> 
+<a class="jxr_linenumber" name="L154" href="#L154">154</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> addBackReference(LZ77Compressor.BackReference block) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L155" href="#L155">155</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> last = writeBlocksAndReturnUnfinishedPair(block.getLength());
+<a class="jxr_linenumber" name="L156" href="#L156">156</a>         last.setBackReference(block);
+<a class="jxr_linenumber" name="L157" href="#L157">157</a>         recordBackReference(block);
+<a class="jxr_linenumber" name="L158" href="#L158">158</a>         clearUnusedBlocksAndPairs();
+<a class="jxr_linenumber" name="L159" href="#L159">159</a>     }
+<a class="jxr_linenumber" name="L160" href="#L160">160</a> 
+<a class="jxr_linenumber" name="L161" href="#L161">161</a>     <strong class="jxr_keyword">private</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> writeBlocksAndReturnUnfinishedPair(<strong class="jxr_keyword">int</strong> length) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L162" href="#L162">162</a>         writeWritablePairs(length);
+<a class="jxr_linenumber" name="L163" href="#L163">163</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> last = pairs.peekLast();
+<a class="jxr_linenumber" name="L164" href="#L164">164</a>         <strong class="jxr_keyword">if</strong> (last == <strong class="jxr_keyword">null</strong> || last.hasBackReference()) {
+<a class="jxr_linenumber" name="L165" href="#L165">165</a>             last = <strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a>();
+<a class="jxr_linenumber" name="L166" href="#L166">166</a>             pairs.addLast(last);
+<a class="jxr_linenumber" name="L167" href="#L167">167</a>         }
+<a class="jxr_linenumber" name="L168" href="#L168">168</a>         <strong class="jxr_keyword">return</strong> last;
+<a class="jxr_linenumber" name="L169" href="#L169">169</a>     }
+<a class="jxr_linenumber" name="L170" href="#L170">170</a> 
+<a class="jxr_linenumber" name="L171" href="#L171">171</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> recordLiteral(byte[] b) {
+<a class="jxr_linenumber" name="L172" href="#L172">172</a>         expandedBlocks.addFirst(b);
+<a class="jxr_linenumber" name="L173" href="#L173">173</a>     }
+<a class="jxr_linenumber" name="L174" href="#L174">174</a> 
+<a class="jxr_linenumber" name="L175" href="#L175">175</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> clearUnusedBlocksAndPairs() {
+<a class="jxr_linenumber" name="L176" href="#L176">176</a>         clearUnusedBlocks();
+<a class="jxr_linenumber" name="L177" href="#L177">177</a>         clearUnusedPairs();
+<a class="jxr_linenumber" name="L178" href="#L178">178</a>     }
+<a class="jxr_linenumber" name="L179" href="#L179">179</a> 
+<a class="jxr_linenumber" name="L180" href="#L180">180</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> clearUnusedBlocks() {
+<a class="jxr_linenumber" name="L181" href="#L181">181</a>         <strong class="jxr_keyword">int</strong> blockLengths = 0;
+<a class="jxr_linenumber" name="L182" href="#L182">182</a>         <strong class="jxr_keyword">int</strong> blocksToKeep = 0;
+<a class="jxr_linenumber" name="L183" href="#L183">183</a>         <strong class="jxr_keyword">for</strong> (byte[] b : expandedBlocks) {
+<a class="jxr_linenumber" name="L184" href="#L184">184</a>             blocksToKeep++;
+<a class="jxr_linenumber" name="L185" href="#L185">185</a>             blockLengths += b.length;
+<a class="jxr_linenumber" name="L186" href="#L186">186</a>             <strong class="jxr_keyword">if</strong> (blockLengths &gt;= BlockLZ4CompressorInputStream.WINDOW_SIZE) {
+<a class="jxr_linenumber" name="L187" href="#L187">187</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L188" href="#L188">188</a>             }
+<a class="jxr_linenumber" name="L189" href="#L189">189</a>         }
+<a class="jxr_linenumber" name="L190" href="#L190">190</a>         <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> size = expandedBlocks.size();
+<a class="jxr_linenumber" name="L191" href="#L191">191</a>         <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">int</strong> i = blocksToKeep; i &lt; size; i++) {
+<a class="jxr_linenumber" name="L192" href="#L192">192</a>             expandedBlocks.removeLast();
+<a class="jxr_linenumber" name="L193" href="#L193">193</a>         }
+<a class="jxr_linenumber" name="L194" href="#L194">194</a>     }
+<a class="jxr_linenumber" name="L195" href="#L195">195</a> 
+<a class="jxr_linenumber" name="L196" href="#L196">196</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> recordBackReference(LZ77Compressor.BackReference block) {
+<a class="jxr_linenumber" name="L197" href="#L197">197</a>         expandedBlocks.addFirst(expand(block.getOffset(), block.getLength()));
+<a class="jxr_linenumber" name="L198" href="#L198">198</a>     }
+<a class="jxr_linenumber" name="L199" href="#L199">199</a> 
+<a class="jxr_linenumber" name="L200" href="#L200">200</a>     <strong class="jxr_keyword">private</strong> byte[] expand(<strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> offset, <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> length) {
+<a class="jxr_linenumber" name="L201" href="#L201">201</a>         byte[] expanded = <strong class="jxr_keyword">new</strong> byte[length];
+<a class="jxr_linenumber" name="L202" href="#L202">202</a>         <strong class="jxr_keyword">if</strong> (offset == 1) { <em class="jxr_comment">// surprisingly common special case</em>
+<a class="jxr_linenumber" name="L203" href="#L203">203</a>             byte[] block = expandedBlocks.peekFirst();
+<a class="jxr_linenumber" name="L204" href="#L204">204</a>             byte b = block[block.length - 1];
+<a class="jxr_linenumber" name="L205" href="#L205">205</a>             <strong class="jxr_keyword">if</strong> (b != 0) { <em class="jxr_comment">// the fresh array contains 0s anyway</em>
+<a class="jxr_linenumber" name="L206" href="#L206">206</a>                 Arrays.fill(expanded, b);
+<a class="jxr_linenumber" name="L207" href="#L207">207</a>             }
+<a class="jxr_linenumber" name="L208" href="#L208">208</a>         } <strong class="jxr_keyword">else</strong> {
+<a class="jxr_linenumber" name="L209" href="#L209">209</a>             expandFromList(expanded, offset, length);
+<a class="jxr_linenumber" name="L210" href="#L210">210</a>         }
+<a class="jxr_linenumber" name="L211" href="#L211">211</a>         <strong class="jxr_keyword">return</strong> expanded;
+<a class="jxr_linenumber" name="L212" href="#L212">212</a>     }
+<a class="jxr_linenumber" name="L213" href="#L213">213</a> 
+<a class="jxr_linenumber" name="L214" href="#L214">214</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> expandFromList(<strong class="jxr_keyword">final</strong> byte[] expanded, <strong class="jxr_keyword">int</strong> offset, <strong class="jxr_keyword">int</strong> length) {
+<a class="jxr_linenumber" name="L215" href="#L215">215</a>         <strong class="jxr_keyword">int</strong> offsetRemaining = offset;
+<a class="jxr_linenumber" name="L216" href="#L216">216</a>         <strong class="jxr_keyword">int</strong> lengthRemaining = length;
+<a class="jxr_linenumber" name="L217" href="#L217">217</a>         <strong class="jxr_keyword">int</strong> writeOffset = 0;
+<a class="jxr_linenumber" name="L218" href="#L218">218</a>         <strong class="jxr_keyword">while</strong> (lengthRemaining &gt; 0) {
+<a class="jxr_linenumber" name="L219" href="#L219">219</a>             <em class="jxr_comment">// find block that contains offsetRemaining</em>
+<a class="jxr_linenumber" name="L220" href="#L220">220</a>             byte[] block = <strong class="jxr_keyword">null</strong>;
+<a class="jxr_linenumber" name="L221" href="#L221">221</a>             <strong class="jxr_keyword">int</strong> copyLen, copyOffset;
+<a class="jxr_linenumber" name="L222" href="#L222">222</a>             <strong class="jxr_keyword">if</strong> (offsetRemaining &gt; 0) {
+<a class="jxr_linenumber" name="L223" href="#L223">223</a>                 <strong class="jxr_keyword">int</strong> blockOffset = 0;
+<a class="jxr_linenumber" name="L224" href="#L224">224</a>                 <strong class="jxr_keyword">for</strong> (byte[] b : expandedBlocks) {
+<a class="jxr_linenumber" name="L225" href="#L225">225</a>                     <strong class="jxr_keyword">if</strong> (b.length + blockOffset &gt;= offsetRemaining) {
+<a class="jxr_linenumber" name="L226" href="#L226">226</a>                         block = b;
+<a class="jxr_linenumber" name="L227" href="#L227">227</a>                         <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L228" href="#L228">228</a>                     }
+<a class="jxr_linenumber" name="L229" href="#L229">229</a>                     blockOffset += b.length;
+<a class="jxr_linenumber" name="L230" href="#L230">230</a>                 }
+<a class="jxr_linenumber" name="L231" href="#L231">231</a>                 <strong class="jxr_keyword">if</strong> (block == <strong class="jxr_keyword">null</strong>) {
+<a class="jxr_linenumber" name="L232" href="#L232">232</a>                     <em class="jxr_comment">// should not be possible</em>
+<a class="jxr_linenumber" name="L233" href="#L233">233</a>                     <strong class="jxr_keyword">throw</strong> <strong class="jxr_keyword">new</strong> IllegalStateException(<span class="jxr_string">"failed to find a block containing offset "</span> + offset);
+<a class="jxr_linenumber" name="L234" href="#L234">234</a>                 }
+<a class="jxr_linenumber" name="L235" href="#L235">235</a>                 copyOffset = blockOffset + block.length - offsetRemaining;
+<a class="jxr_linenumber" name="L236" href="#L236">236</a>                 copyLen = Math.min(lengthRemaining, block.length - copyOffset);
+<a class="jxr_linenumber" name="L237" href="#L237">237</a>             } <strong class="jxr_keyword">else</strong> {
+<a class="jxr_linenumber" name="L238" href="#L238">238</a>                 <em class="jxr_comment">// offsetRemaining is negative and points into the expanded bytes</em>
+<a class="jxr_linenumber" name="L239" href="#L239">239</a>                 block = expanded;
+<a class="jxr_linenumber" name="L240" href="#L240">240</a>                 copyOffset = writeOffset  + offsetRemaining;
+<a class="jxr_linenumber" name="L241" href="#L241">241</a>                 copyLen = Math.min(lengthRemaining, writeOffset + offsetRemaining);
+<a class="jxr_linenumber" name="L242" href="#L242">242</a>             }
+<a class="jxr_linenumber" name="L243" href="#L243">243</a>             System.arraycopy(block, copyOffset, expanded, writeOffset, copyLen);
+<a class="jxr_linenumber" name="L244" href="#L244">244</a>             offsetRemaining -= copyLen;
+<a class="jxr_linenumber" name="L245" href="#L245">245</a>             lengthRemaining -= copyLen;
+<a class="jxr_linenumber" name="L246" href="#L246">246</a>             writeOffset += copyLen;
+<a class="jxr_linenumber" name="L247" href="#L247">247</a>         }
+<a class="jxr_linenumber" name="L248" href="#L248">248</a>     }
+<a class="jxr_linenumber" name="L249" href="#L249">249</a> 
+<a class="jxr_linenumber" name="L250" href="#L250">250</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> clearUnusedPairs() {
+<a class="jxr_linenumber" name="L251" href="#L251">251</a>         <strong class="jxr_keyword">int</strong> pairLengths = 0;
+<a class="jxr_linenumber" name="L252" href="#L252">252</a>         <strong class="jxr_keyword">int</strong> pairsToKeep = 0;
+<a class="jxr_linenumber" name="L253" href="#L253">253</a>         <strong class="jxr_keyword">for</strong> (Iterator&lt;Pair&gt; it = pairs.descendingIterator(); it.hasNext(); ) {
+<a class="jxr_linenumber" name="L254" href="#L254">254</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = it.next();
+<a class="jxr_linenumber" name="L255" href="#L255">255</a>             pairsToKeep++;
+<a class="jxr_linenumber" name="L256" href="#L256">256</a>             pairLengths += p.length();
+<a class="jxr_linenumber" name="L257" href="#L257">257</a>             <strong class="jxr_keyword">if</strong> (pairLengths &gt;= BlockLZ4CompressorInputStream.WINDOW_SIZE) {
+<a class="jxr_linenumber" name="L258" href="#L258">258</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L259" href="#L259">259</a>             }
+<a class="jxr_linenumber" name="L260" href="#L260">260</a>         }
+<a class="jxr_linenumber" name="L261" href="#L261">261</a>         <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> size = pairs.size();
+<a class="jxr_linenumber" name="L262" href="#L262">262</a>         <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">int</strong> i = pairsToKeep; i &lt; size; i++) {
+<a class="jxr_linenumber" name="L263" href="#L263">263</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = pairs.peekFirst();
+<a class="jxr_linenumber" name="L264" href="#L264">264</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
+<a class="jxr_linenumber" name="L265" href="#L265">265</a>                 pairs.removeFirst();
+<a class="jxr_linenumber" name="L266" href="#L266">266</a>             } <strong class="jxr_keyword">else</strong> {
+<a class="jxr_linenumber" name="L267" href="#L267">267</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L268" href="#L268">268</a>             }
+<a class="jxr_linenumber" name="L269" href="#L269">269</a>         }
+<a class="jxr_linenumber" name="L270" href="#L270">270</a>     }
+<a class="jxr_linenumber" name="L271" href="#L271">271</a> 
+<a class="jxr_linenumber" name="L272" href="#L272">272</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> writeFinalLiteralBlock() <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L273" href="#L273">273</a>         rewriteLastPairs();
+<a class="jxr_linenumber" name="L274" href="#L274">274</a>         <strong class="jxr_keyword">for</strong> (Pair p : pairs) {
+<a class="jxr_linenumber" name="L275" href="#L275">275</a>             <strong class="jxr_keyword">if</strong> (!p.hasBeenWritten()) {
+<a class="jxr_linenumber" name="L276" href="#L276">276</a>                 p.writeTo(os);
+<a class="jxr_linenumber" name="L277" href="#L277">277</a>             }
+<a class="jxr_linenumber" name="L278" href="#L278">278</a>         }
+<a class="jxr_linenumber" name="L279" href="#L279">279</a>         pairs.clear();
+<a class="jxr_linenumber" name="L280" href="#L280">280</a>     }
+<a class="jxr_linenumber" name="L281" href="#L281">281</a> 
+<a class="jxr_linenumber" name="L282" href="#L282">282</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> writeWritablePairs(<strong class="jxr_keyword">int</strong> lengthOfBlocksAfterLastPair) <strong class="jxr_keyword">throws</strong> IOException {
+<a class="jxr_linenumber" name="L283" href="#L283">283</a>         <strong class="jxr_keyword">int</strong> unwrittenLength = lengthOfBlocksAfterLastPair;
+<a class="jxr_linenumber" name="L284" href="#L284">284</a>         <strong class="jxr_keyword">for</strong> (Iterator&lt;Pair&gt; it = pairs.descendingIterator(); it.hasNext(); ) {
+<a class="jxr_linenumber" name="L285" href="#L285">285</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = it.next();
+<a class="jxr_linenumber" name="L286" href="#L286">286</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
+<a class="jxr_linenumber" name="L287" href="#L287">287</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L288" href="#L288">288</a>             }
+<a class="jxr_linenumber" name="L289" href="#L289">289</a>             unwrittenLength += p.length();
+<a class="jxr_linenumber" name="L290" href="#L290">290</a>         }
+<a class="jxr_linenumber" name="L291" href="#L291">291</a>         <strong class="jxr_keyword">for</strong> (Pair p : pairs) {
+<a class="jxr_linenumber" name="L292" href="#L292">292</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
+<a class="jxr_linenumber" name="L293" href="#L293">293</a>                 <strong class="jxr_keyword">continue</strong>;
+<a class="jxr_linenumber" name="L294" href="#L294">294</a>             }
+<a class="jxr_linenumber" name="L295" href="#L295">295</a>             unwrittenLength -= p.length();
+<a class="jxr_linenumber" name="L296" href="#L296">296</a>             <strong class="jxr_keyword">if</strong> (p.canBeWritten(unwrittenLength)) {
+<a class="jxr_linenumber" name="L297" href="#L297">297</a>                 p.writeTo(os);
+<a class="jxr_linenumber" name="L298" href="#L298">298</a>             } <strong class="jxr_keyword">else</strong> {
+<a class="jxr_linenumber" name="L299" href="#L299">299</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L300" href="#L300">300</a>             }
+<a class="jxr_linenumber" name="L301" href="#L301">301</a>         }
+<a class="jxr_linenumber" name="L302" href="#L302">302</a>     }
+<a class="jxr_linenumber" name="L303" href="#L303">303</a> 
+<a class="jxr_linenumber" name="L304" href="#L304">304</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> rewriteLastPairs() {
+<a class="jxr_linenumber" name="L305" href="#L305">305</a>         LinkedList&lt;Pair&gt; lastPairs = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
+<a class="jxr_linenumber" name="L306" href="#L306">306</a>         LinkedList&lt;Integer&gt; pairLength = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
+<a class="jxr_linenumber" name="L307" href="#L307">307</a>         <strong class="jxr_keyword">int</strong> offset = 0;
+<a class="jxr_linenumber" name="L308" href="#L308">308</a>         <strong class="jxr_keyword">for</strong> (Iterator&lt;Pair&gt; it = pairs.descendingIterator(); it.hasNext(); ) {
+<a class="jxr_linenumber" name="L309" href="#L309">309</a>             <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> p = it.next();
+<a class="jxr_linenumber" name="L310" href="#L310">310</a>             <strong class="jxr_keyword">if</strong> (p.hasBeenWritten()) {
+<a class="jxr_linenumber" name="L311" href="#L311">311</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L312" href="#L312">312</a>             }
+<a class="jxr_linenumber" name="L313" href="#L313">313</a>             <strong class="jxr_keyword">int</strong> len = p.length();
+<a class="jxr_linenumber" name="L314" href="#L314">314</a>             pairLength.addFirst(len);
+<a class="jxr_linenumber" name="L315" href="#L315">315</a>             lastPairs.addFirst(p);
+<a class="jxr_linenumber" name="L316" href="#L316">316</a>             offset += len;
+<a class="jxr_linenumber" name="L317" href="#L317">317</a>             <strong class="jxr_keyword">if</strong> (offset &gt;= MIN_OFFSET_OF_LAST_BACK_REFERENCE) {
+<a class="jxr_linenumber" name="L318" href="#L318">318</a>                 <strong class="jxr_keyword">break</strong>;
+<a class="jxr_linenumber" name="L319" href="#L319">319</a>             }
 <a class="jxr_linenumber" name="L320" href="#L320">320</a>         }
-<a class="jxr_linenumber" name="L321" href="#L321">321</a>         <em class="jxr_comment">// lastPairs may contain between one and four Pairs:</em>
-<a class="jxr_linenumber" name="L322" href="#L322">322</a>         <em class="jxr_comment">// * the last pair may be a one byte literal</em>
-<a class="jxr_linenumber" name="L323" href="#L323">323</a>         <em class="jxr_comment">// * all other Pairs contain a back-reference which must be four bytes long at minimum</em>
-<a class="jxr_linenumber" name="L324" href="#L324">324</a>         <em class="jxr_comment">// we could merge them all into a single literal block but</em>
-<a class="jxr_linenumber" name="L325" href="#L325">325</a>         <em class="jxr_comment">// this may harm compression. For example compressing</em>
-<a class="jxr_linenumber" name="L326" href="#L326">326</a>         <em class="jxr_comment">// "bla.tar" from our tests yields a last block containing a</em>
-<a class="jxr_linenumber" name="L327" href="#L327">327</a>         <em class="jxr_comment">// back-reference of length &gt; 2k and we'd end up with a last</em>
-<a class="jxr_linenumber" name="L328" href="#L328">328</a>         <em class="jxr_comment">// literal of that size rather than a 2k back-reference and a</em>
-<a class="jxr_linenumber" name="L329" href="#L329">329</a>         <em class="jxr_comment">// 12 byte literal at the end.</em>
-<a class="jxr_linenumber" name="L330" href="#L330">330</a> 
-<a class="jxr_linenumber" name="L331" href="#L331">331</a>         <em class="jxr_comment">// Instead we merge all but the first of lastPairs into a new</em>
-<a class="jxr_linenumber" name="L332" href="#L332">332</a>         <em class="jxr_comment">// literal-only Pair "replacement" and look at the</em>
-<a class="jxr_linenumber" name="L333" href="#L333">333</a>         <em class="jxr_comment">// back-reference in the first of lastPairs and see if we can</em>
-<a class="jxr_linenumber" name="L334" href="#L334">334</a>         <em class="jxr_comment">// split it. We can split it if it is longer than 16 -</em>
-<a class="jxr_linenumber" name="L335" href="#L335">335</a>         <em class="jxr_comment">// replacement.length (i.e. the minimal length of four is kept</em>
-<a class="jxr_linenumber" name="L336" href="#L336">336</a>         <em class="jxr_comment">// while making sure the last literal is at least twelve bytes</em>
-<a class="jxr_linenumber" name="L337" href="#L337">337</a>         <em class="jxr_comment">// long). If we can't split it, we expand the first of the pairs</em>
-<a class="jxr_linenumber" name="L338" href="#L338">338</a>         <em class="jxr_comment">// as well.</em>
-<a class="jxr_linenumber" name="L339" href="#L339">339</a> 
-<a class="jxr_linenumber" name="L340" href="#L340">340</a>         <em class="jxr_comment">// this is not optimal, we could get better compression</em>
-<a class="jxr_linenumber" name="L341" href="#L341">341</a>         <em class="jxr_comment">// results with more complex approaches as the last literal</em>
-<a class="jxr_linenumber" name="L342" href="#L342">342</a>         <em class="jxr_comment">// only needs to be five bytes long if the previous</em>
-<a class="jxr_linenumber" name="L343" href="#L343">343</a>         <em class="jxr_comment">// back-reference has an offset big enough</em>
-<a class="jxr_linenumber" name="L344" href="#L344">344</a> 
-<a class="jxr_linenumber" name="L345" href="#L345">345</a>         <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> lastPairsSize = lastPairs.size();
-<a class="jxr_linenumber" name="L346" href="#L346">346</a>         <strong class="jxr_keyword">int</strong> toExpand = 0;
-<a class="jxr_linenumber" name="L347" href="#L347">347</a>         <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">int</strong> i = 1; i &lt; lastPairsSize; i++) {
-<a class="jxr_linenumber" name="L348" href="#L348">348</a>             toExpand += pairLength.get(i);
-<a class="jxr_linenumber" name="L349" href="#L349">349</a>         }
-<a class="jxr_linenumber" name="L350" href="#L350">350</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> replacement = <strong class="jxr_keyword">new</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a>();
-<a class="jxr_linenumber" name="L351" href="#L351">351</a>         <strong class="jxr_keyword">if</strong> (toExpand &gt; 0) {
-<a class="jxr_linenumber" name="L352" href="#L352">352</a>             replacement.prependLiteral(expand(toExpand, toExpand));
-<a class="jxr_linenumber" name="L353" href="#L353">353</a>         }
-<a class="jxr_linenumber" name="L354" href="#L354">354</a>         <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> splitCandidate = lastPairs.get(0);
-<a class="jxr_linenumber" name="L355" href="#L355">355</a>         <strong class="jxr_keyword">int</strong> stillNeeded = MIN_OFFSET_OF_LAST_BACK_REFERENCE - toExpand;
-<a class="jxr_linenumber" name="L356" href="#L356">356</a>         <strong class="jxr_keyword">if</strong> (splitCandidate.hasBackReference()
-<a class="jxr_linenumber" name="L357" href="#L357">357</a>             &amp;&amp; splitCandidate.backReferenceLength() &gt;= MIN_BACK_REFERENCE_LENGTH + stillNeeded) {
-<a class="jxr_linenumber" name="L358" href="#L358">358</a>             replacement.prependLiteral(expand(toExpand + stillNeeded, stillNeeded));
-<a class="jxr_linenumber" name="L359" href="#L359">359</a>             pairs.add(splitCandidate.splitWithNewBackReferenceLengthOf(splitCandidate.backReferenceLength()
-<a class="jxr_linenumber" name="L360" href="#L360">360</a>                 - stillNeeded));
-<a class="jxr_linenumber" name="L361" href="#L361">361</a>         } <strong class="jxr_keyword">else</strong> {
-<a class="jxr_linenumber" name="L362" href="#L362">362</a>             <strong class="jxr_keyword">if</strong> (splitCandidate.hasBackReference()) {
-<a class="jxr_linenumber" name="L363" href="#L363">363</a>                 <strong class="jxr_keyword">int</strong> brLen = splitCandidate.backReferenceLength();
-<a class="jxr_linenumber" name="L364" href="#L364">364</a>                 replacement.prependLiteral(expand(toExpand + brLen, brLen));
-<a class="jxr_linenumber" name="L365" href="#L365">365</a>             }
-<a class="jxr_linenumber" name="L366" href="#L366">366</a>             splitCandidate.prependTo(replacement);
-<a class="jxr_linenumber" name="L367" href="#L367">367</a>         }
-<a class="jxr_linenumber" name="L368" href="#L368">368</a>         pairs.add(replacement);
-<a class="jxr_linenumber" name="L369" href="#L369">369</a>     }
-<a class="jxr_linenumber" name="L370" href="#L370">370</a> 
-<a class="jxr_linenumber" name="L371" href="#L371">371</a>     <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../../../org/apache/commons/compress/compressors/lz4/BlockLZ4CompressorOutputStream.html">Pair</a> {
-<a class="jxr_linenumber" name="L372" href="#L372">372</a>         <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> Deque&lt;byte[]&gt; literals = <strong class="jxr_keyword">new</strong> LinkedList&lt;&gt;();
-<a class="jxr_linenumber" name="L373" href="#L373">373</a>         <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">int</strong> brOffset, brLength;
-<a class="jxr_linenumber" name="L374" href="#L374">374</a>         <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">boolean</strong> written;
-<a class="jxr_linenumber" name="L375" href="#L375">375</a> 
-<a class="jxr_linenumber" name="L376" href="#L376">376</a>         <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">void</strong> prependLiteral(byte[] data) {
-<a class="jxr_linenumber" name="L377" href="#L377">377</a>             literals.addFirst(data);
-<a class="jxr_linenumber" name="L378" href="#L378">378</a>         }
-<a class="jxr_linenumber" name="L379" href="#L379">379</a>         byte[] addLiteral(LZ77Compressor.LiteralBlock block) {
-<a class="jxr_linenumber" name="L380" href="#L380">380</a>             byte[] copy = Arrays.copyOfRange(block.getData(), block.getOffset(),
-<a class="jxr_linenumber" name="L381" href="#L381">381</a>                 block.getOffset() + block.getLength());
-<a class="jxr_linenumber" name="L382" href="#L382">382</a>             literals.add(copy);
-<a class="jxr_linenumber" name="L383" href="#L383">383</a>             <strong class="jxr_keyword">return</strong> copy;
-<a class="jxr_linenumber" name="L384" href="#L384">384</a>         }
-<a class="jxr_linenumber" name="L385" href="#L385">385</a>         <strong class="jxr_keyword">void</strong> setBackReference(LZ77Compressor.BackReference block) {
-<a class="jxr_linenumber" name="L386" href="#L386">386</a>             <strong class="jxr_keyword">if</strong> (hasBackReference()) {
-<a class="jxr_linenumber" name="L387" href="#L387">387</a>                 <strong class="jxr_keyword">throw</strong> <strong class="jxr_keyword">new</strong> IllegalStateException();
-<a class="jxr_linenumber" name="L388" href="#L388">388</a>             }
-<a class="jxr_linenumber" name="L389" href="#L389">389</a>             brOffset = block.getOffset();
-<a class="jxr_linenumber" name="L390" href="#L390">390</a>             brLength = block.getLength();
-<a class="jxr_linenumber" name="L391" href="#L391">391</a>         }
-<a class="jxr_linenumber" name="L392" href="#L392">392</a>         <strong class="jxr_keyword">boolean</strong> hasBackReference() {
-<a class="jxr_linenumber" name="L393" href="#L393">393</a>             <strong class="jxr_keyword">return</strong> brOffset &gt; 0;
+<a class="jxr_linenumber" name="L321" href="#L321">321</a>         <strong class="jxr_keyword">for</strong> (Pair p : lastPairs) {
+<a class="jxr_linenumber" name="L322" href="#L322">322</a>             pairs.remove(p);
+<a class="jxr_linenumber" name="L323" href="#L323">323</a>         }
+<a class="jxr_linenumber" name="L324" href="#L324">324</a>         <em class="jxr_comment">// lastPairs may contain between one and four Pairs:</em>
+<a class="jxr_linenumber" name="L325" href="#L325">325</a>         <em class="jxr_comment">// * the last pair may be a one byte literal</em>
+<a class="jxr_linenumber" name="L326" href="#L326">326</a>         <em class="jxr_comment">// * all other Pairs contain a back-reference which must be four bytes long at minimum</em>
+<a class="jxr_linenumber" name="L327" href="#L327">327</a>         <em class="jxr_comment">// we could merge them all into a single literal block but</em>
+<a class="jxr_linenumber" name="L328" href="#L328">328</a>         <em class="jxr_comment">// this may harm compression. For example compressing</em>
+<a class="jxr_linenumber" name="L329" href="#L329">329</a>         <em class="jxr_comment">// "bla.tar" from our tests yields a last block containing a</em>
+<a class="jxr_linenumber" name="L330" href="#L330">330</a>         <em class="jxr_comment">// back-reference of length &gt; 2k and we'd end up with a last</em>
+<a class="jxr_linenumber" name="L331" href="#L331">331</a>         <em class="jxr_comment">// literal of that size rather than a 2k back-reference and a</em>
+<a class="jxr_linenumber" name="L332" href="#L332">332</a>         <em class="jxr_comment">// 12 byte literal at the end.</em>
+<a class="jxr_linenumber" name="L333" href="#L333">333</a> 
+<a class="jxr_linenumber" name="L334" href="#L334">334</a>         <em class="jxr_comment">// Instead we merge all but the first of lastPairs into a new</em>
+<a class="jxr_linenumber" name="L335" href="#L335">335</a>         <em class="jxr_comment">// literal-only Pair "replacement" and look at the</em>
+<a class="jxr_linenumber" name="L336" href="#L336">336</a>         <em class="jxr_comment">// back-reference in the first of lastPairs and see if we can</em>
+<a class="jxr_linenumber" name="L337" href="#L337">337</a>         <em class="jxr_comment">// split it. We can split it if it is longer than 16 -</em>
+<a class="jxr_linenumber" name="L338" href="#L338">338</a>         <em class="jxr_comment">// replacement.length (i.e. the minimal length of four is kept</em>
+<a class="jxr_linenumber" name="L339" href="#L339">339</a>         <em class="jxr_comment">// while making sure the last literal is at least twelve bytes</em>
+<a class="jxr_linenumber" name="L340" href="#L340">340</a>         <em class="jxr_comment">// long). If we can't split it, we expand the first of the pairs</em>
+<a class="jxr_linenumber" name="L341" href="#L341">341</a>         <em class="jxr_comment">// as well.</em>
+<a class="jxr_linenumber" name="L342" href="#L342">342</a> 
+<a class="jxr_linenumber" name="L343" href="#L343">343</a>         <em class="jxr_comment">// this is not optimal, we could get better compression</em>
+<a class="jxr_linenumber" name="L344" href="#L344">344</a>         <em class="jxr_comment">// results with more complex approaches as the last literal</em>
+<a class="jxr_linenumber" name="L345" href="#L345">345</a>         <em class="jxr_comment">// only needs to be five bytes long if the previous</em>
+<a class="jxr_linenumber" name="L346" href="#L346">346</a>         <em class="jxr_comment">// back-reference has an offset big enough</em>
+<a class="jxr_linenumber" name="L347" href="#L347">347</a> 
+<a class="jxr_linenumber" name="L348" href="#L348">348</a>         <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> lastPairsSize = lastPairs.size();

[... 179 lines stripped ...]


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