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<pre><span class="sourceLineNo">001</span>/**<a name="line.1"></a>
<span class="sourceLineNo">002</span> *<a name="line.2"></a>
<span class="sourceLineNo">003</span> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.3"></a>
<span class="sourceLineNo">004</span> * or more contributor license agreements. See the NOTICE file<a name="line.4"></a>
<span class="sourceLineNo">005</span> * distributed with this work for additional information<a name="line.5"></a>
<span class="sourceLineNo">006</span> * regarding copyright ownership. The ASF licenses this file<a name="line.6"></a>
<span class="sourceLineNo">007</span> * to you under the Apache License, Cellersion 2.0 (the<a name="line.7"></a>
<span class="sourceLineNo">008</span> * "License"); you may not use this file except in compliance<a name="line.8"></a>
<span class="sourceLineNo">009</span> * with the License. You may obtain a copy of the License at<a name="line.9"></a>
<span class="sourceLineNo">010</span> *<a name="line.10"></a>
<span class="sourceLineNo">011</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.11"></a>
<span class="sourceLineNo">012</span> *<a name="line.12"></a>
<span class="sourceLineNo">013</span> * Unless required by applicable law or agreed to in writing, software<a name="line.13"></a>
<span class="sourceLineNo">014</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.14"></a>
<span class="sourceLineNo">015</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY CellIND, either express or implied.<a name="line.15"></a>
<span class="sourceLineNo">016</span> * See the License for the specific language governing permissions and<a name="line.16"></a>
<span class="sourceLineNo">017</span> * limitations under the License.<a name="line.17"></a>
<span class="sourceLineNo">018</span> */<a name="line.18"></a>
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>package org.apache.hadoop.hbase.regionserver;<a name="line.20"></a>
<span class="sourceLineNo">021</span><a name="line.21"></a>
<span class="sourceLineNo">022</span>import java.nio.ByteBuffer;<a name="line.22"></a>
<span class="sourceLineNo">023</span><a name="line.23"></a>
<span class="sourceLineNo">024</span>import org.apache.hadoop.hbase.Cell;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import org.apache.hadoop.hbase.util.Bytes;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import org.apache.hadoop.hbase.util.ByteBufferUtils;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import org.apache.hadoop.hbase.util.ClassSize;<a name="line.28"></a>
<span class="sourceLineNo">029</span><a name="line.29"></a>
<span class="sourceLineNo">030</span>import java.util.Comparator;<a name="line.30"></a>
<span class="sourceLineNo">031</span><a name="line.31"></a>
<span class="sourceLineNo">032</span><a name="line.32"></a>
<span class="sourceLineNo">033</span>/**<a name="line.33"></a>
<span class="sourceLineNo">034</span> * CellChunkMap is an array of serialized representations of Cell<a name="line.34"></a>
<span class="sourceLineNo">035</span> * (pointing to Chunks with full Cell data) and can be allocated both off-heap and on-heap.<a name="line.35"></a>
<span class="sourceLineNo">036</span> *<a name="line.36"></a>
<span class="sourceLineNo">037</span> * CellChunkMap is a byte array (chunk) holding all that is needed to access a Cell, which<a name="line.37"></a>
<span class="sourceLineNo">038</span> * is actually saved on another deeper chunk.<a name="line.38"></a>
<span class="sourceLineNo">039</span> * Per Cell we have a reference to this deeper byte array B (chunk ID, integer),<a name="line.39"></a>
<span class="sourceLineNo">040</span> * offset in bytes in B (integer), length in bytes in B (integer) and seqID of the cell (long).<a name="line.40"></a>
<span class="sourceLineNo">041</span> * In order to save reference to byte array we use the Chunk's ID given by ChunkCreator.<a name="line.41"></a>
<span class="sourceLineNo">042</span> *<a name="line.42"></a>
<span class="sourceLineNo">043</span> * The CellChunkMap memory layout on chunk A relevant to a deeper byte array B,<a name="line.43"></a>
<span class="sourceLineNo">044</span> * holding the actual cell data:<a name="line.44"></a>
<span class="sourceLineNo">045</span> *<a name="line.45"></a>
<span class="sourceLineNo">046</span> * &lt; header &gt; &lt;--------------- first Cell -----------------&gt; &lt;-- second Cell ...<a name="line.46"></a>
<span class="sourceLineNo">047</span> * --------------------------------------------------------------------------------------- ...<a name="line.47"></a>
<span class="sourceLineNo">048</span> * integer | integer | integer | integer | long |<a name="line.48"></a>
<span class="sourceLineNo">049</span> * 4 bytes | 4 bytes | 4 bytes | 4 bytes | 8 bytes |<a name="line.49"></a>
<span class="sourceLineNo">050</span> * ChunkID | chunkID of | offset in B | length of | sequence | ...<a name="line.50"></a>
<span class="sourceLineNo">051</span> * of this | chunk B with | where Cell's | Cell's | ID of |<a name="line.51"></a>
<span class="sourceLineNo">052</span> * chunk A | Cell data | data starts | data in B | the Cell |<a name="line.52"></a>
<span class="sourceLineNo">053</span> * --------------------------------------------------------------------------------------- ...<a name="line.53"></a>
<span class="sourceLineNo">054</span> */<a name="line.54"></a>
<span class="sourceLineNo">055</span>@InterfaceAudience.Private<a name="line.55"></a>
<span class="sourceLineNo">056</span>public class CellChunkMap extends CellFlatMap {<a name="line.56"></a>
<span class="sourceLineNo">057</span><a name="line.57"></a>
<span class="sourceLineNo">058</span> private final Chunk[] chunks; // the array of chunks, on which the index is based<a name="line.58"></a>
<span class="sourceLineNo">059</span><a name="line.59"></a>
<span class="sourceLineNo">060</span> // number of cell-representations in a chunk<a name="line.60"></a>
<span class="sourceLineNo">061</span> // depends on the size of the chunks (may be index chunks or regular data chunks)<a name="line.61"></a>
<span class="sourceLineNo">062</span> // each chunk starts with its own ID following the cells data<a name="line.62"></a>
<span class="sourceLineNo">063</span> private final int numOfCellRepsInChunk;<a name="line.63"></a>
<span class="sourceLineNo">064</span><a name="line.64"></a>
<span class="sourceLineNo">065</span> /**<a name="line.65"></a>
<span class="sourceLineNo">066</span> * C-tor for creating CellChunkMap from existing Chunk array, which must be ordered<a name="line.66"></a>
<span class="sourceLineNo">067</span> * (decreasingly or increasingly according to parameter "descending")<a name="line.67"></a>
<span class="sourceLineNo">068</span> * @param comparator a tool for comparing cells<a name="line.68"></a>
<span class="sourceLineNo">069</span> * @param chunks ordered array of index chunk with cell representations<a name="line.69"></a>
<span class="sourceLineNo">070</span> * @param min the index of the first cell (usually 0)<a name="line.70"></a>
<span class="sourceLineNo">071</span> * @param max number of Cells or the index of the cell after the maximal cell<a name="line.71"></a>
<span class="sourceLineNo">072</span> * @param descending the order of the given array<a name="line.72"></a>
<span class="sourceLineNo">073</span> */<a name="line.73"></a>
<span class="sourceLineNo">074</span> public CellChunkMap(Comparator&lt;? super Cell&gt; comparator,<a name="line.74"></a>
<span class="sourceLineNo">075</span> Chunk[] chunks, int min, int max, boolean descending) {<a name="line.75"></a>
<span class="sourceLineNo">076</span> super(comparator, min, max, descending);<a name="line.76"></a>
<span class="sourceLineNo">077</span> this.chunks = chunks;<a name="line.77"></a>
<span class="sourceLineNo">078</span> if (chunks != null &amp;&amp; chunks.length != 0 &amp;&amp; chunks[0] != null) {<a name="line.78"></a>
<span class="sourceLineNo">079</span> this.numOfCellRepsInChunk = (chunks[0].size - ChunkCreator.SIZEOF_CHUNK_HEADER) /<a name="line.79"></a>
<span class="sourceLineNo">080</span> ClassSize.CELL_CHUNK_MAP_ENTRY;<a name="line.80"></a>
<span class="sourceLineNo">081</span> } else { // In case the chunks array was not allocated<a name="line.81"></a>
<span class="sourceLineNo">082</span> this.numOfCellRepsInChunk = 0;<a name="line.82"></a>
<span class="sourceLineNo">083</span> }<a name="line.83"></a>
<span class="sourceLineNo">084</span> }<a name="line.84"></a>
<span class="sourceLineNo">085</span><a name="line.85"></a>
<span class="sourceLineNo">086</span> /* To be used by base (CellFlatMap) class only to create a sub-CellFlatMap<a name="line.86"></a>
<span class="sourceLineNo">087</span> * Should be used only to create only CellChunkMap from CellChunkMap */<a name="line.87"></a>
<span class="sourceLineNo">088</span> @Override<a name="line.88"></a>
<span class="sourceLineNo">089</span> protected CellFlatMap createSubCellFlatMap(int min, int max, boolean descending) {<a name="line.89"></a>
<span class="sourceLineNo">090</span> return new CellChunkMap(this.comparator(), this.chunks, min, max, descending);<a name="line.90"></a>
<span class="sourceLineNo">091</span> }<a name="line.91"></a>
<span class="sourceLineNo">092</span><a name="line.92"></a>
<span class="sourceLineNo">093</span><a name="line.93"></a>
<span class="sourceLineNo">094</span> @Override<a name="line.94"></a>
<span class="sourceLineNo">095</span> protected Cell getCell(int i) {<a name="line.95"></a>
<span class="sourceLineNo">096</span> // get the index of the relevant chunk inside chunk array<a name="line.96"></a>
<span class="sourceLineNo">097</span> int chunkIndex = (i / numOfCellRepsInChunk);<a name="line.97"></a>
<span class="sourceLineNo">098</span> ByteBuffer block = chunks[chunkIndex].getData();// get the ByteBuffer of the relevant chunk<a name="line.98"></a>
<span class="sourceLineNo">099</span> int j = i - chunkIndex * numOfCellRepsInChunk; // get the index of the cell-representation<a name="line.99"></a>
<span class="sourceLineNo">100</span><a name="line.100"></a>
<span class="sourceLineNo">101</span> // find inside the offset inside the chunk holding the index, skip bytes for chunk id<a name="line.101"></a>
<span class="sourceLineNo">102</span> int offsetInBytes = ChunkCreator.SIZEOF_CHUNK_HEADER + j* ClassSize.CELL_CHUNK_MAP_ENTRY;<a name="line.102"></a>
<span class="sourceLineNo">103</span><a name="line.103"></a>
<span class="sourceLineNo">104</span> // find the chunk holding the data of the cell, the chunkID is stored first<a name="line.104"></a>
<span class="sourceLineNo">105</span> int chunkId = ByteBufferUtils.toInt(block, offsetInBytes);<a name="line.105"></a>
<span class="sourceLineNo">106</span> Chunk chunk = ChunkCreator.getInstance().getChunk(chunkId);<a name="line.106"></a>
<span class="sourceLineNo">107</span> if (chunk == null) {<a name="line.107"></a>
<span class="sourceLineNo">108</span> // this should not happen<a name="line.108"></a>
<span class="sourceLineNo">109</span> throw new IllegalArgumentException("In CellChunkMap, cell must be associated with chunk."<a name="line.109"></a>
<span class="sourceLineNo">110</span> + ". We were looking for a cell at index " + i);<a name="line.110"></a>
<span class="sourceLineNo">111</span> }<a name="line.111"></a>
<span class="sourceLineNo">112</span><a name="line.112"></a>
<span class="sourceLineNo">113</span> // find the offset of the data of the cell, skip integer for chunkID, offset is stored second<a name="line.113"></a>
<span class="sourceLineNo">114</span> int offsetOfCell = ByteBufferUtils.toInt(block, offsetInBytes + Bytes.SIZEOF_INT);<a name="line.114"></a>
<span class="sourceLineNo">115</span> // find the length of the data of the cell, skip two integers for chunkID and offset,<a name="line.115"></a>
<span class="sourceLineNo">116</span> // length is stored third<a name="line.116"></a>
<span class="sourceLineNo">117</span> int lengthOfCell = ByteBufferUtils.toInt(block, offsetInBytes + 2*Bytes.SIZEOF_INT);<a name="line.117"></a>
<span class="sourceLineNo">118</span> // find the seqID of the cell, skip three integers for chunkID, offset, and length<a name="line.118"></a>
<span class="sourceLineNo">119</span> // the seqID is plain written as part of the cell representation<a name="line.119"></a>
<span class="sourceLineNo">120</span> long cellSeqID = ByteBufferUtils.toLong(block, offsetInBytes + 3*Bytes.SIZEOF_INT);<a name="line.120"></a>
<span class="sourceLineNo">121</span><a name="line.121"></a>
<span class="sourceLineNo">122</span> ByteBuffer buf = chunk.getData(); // get the ByteBuffer where the cell data is stored<a name="line.122"></a>
<span class="sourceLineNo">123</span> if (buf == null) {<a name="line.123"></a>
<span class="sourceLineNo">124</span> // this should not happen<a name="line.124"></a>
<span class="sourceLineNo">125</span> throw new IllegalArgumentException("In CellChunkMap, chunk must be associated with ByteBuffer."<a name="line.125"></a>
<span class="sourceLineNo">126</span> + " Chunk: " + chunk + " Chunk ID: " + chunk.getId() + ", is from pool: "<a name="line.126"></a>
<span class="sourceLineNo">127</span> + chunk.isFromPool() + ". We were looking for a cell at index " + i);<a name="line.127"></a>
<span class="sourceLineNo">128</span> }<a name="line.128"></a>
<span class="sourceLineNo">129</span><a name="line.129"></a>
<span class="sourceLineNo">130</span> return new ByteBufferChunkKeyValue(buf, offsetOfCell, lengthOfCell, cellSeqID);<a name="line.130"></a>
<span class="sourceLineNo">131</span> }<a name="line.131"></a>
<span class="sourceLineNo">132</span>}<a name="line.132"></a>
</pre>
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