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<pre><span class="source-line-no">001</span><span id="line-1">/*</span>
<span class="source-line-no">002</span><span id="line-2"> * Licensed to the Apache Software Foundation (ASF) under one</span>
<span class="source-line-no">003</span><span id="line-3"> * or more contributor license agreements. See the NOTICE file</span>
<span class="source-line-no">004</span><span id="line-4"> * distributed with this work for additional information</span>
<span class="source-line-no">005</span><span id="line-5"> * regarding copyright ownership. The ASF licenses this file</span>
<span class="source-line-no">006</span><span id="line-6"> * to you under the Apache License, Version 2.0 (the</span>
<span class="source-line-no">007</span><span id="line-7"> * "License"); you may not use this file except in compliance</span>
<span class="source-line-no">008</span><span id="line-8"> * with the License. You may obtain a copy of the License at</span>
<span class="source-line-no">009</span><span id="line-9"> *</span>
<span class="source-line-no">010</span><span id="line-10"> * http://www.apache.org/licenses/LICENSE-2.0</span>
<span class="source-line-no">011</span><span id="line-11"> *</span>
<span class="source-line-no">012</span><span id="line-12"> * Unless required by applicable law or agreed to in writing, software</span>
<span class="source-line-no">013</span><span id="line-13"> * distributed under the License is distributed on an "AS IS" BASIS,</span>
<span class="source-line-no">014</span><span id="line-14"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span>
<span class="source-line-no">015</span><span id="line-15"> * See the License for the specific language governing permissions and</span>
<span class="source-line-no">016</span><span id="line-16"> * limitations under the License.</span>
<span class="source-line-no">017</span><span id="line-17"> */</span>
<span class="source-line-no">018</span><span id="line-18">package org.apache.hadoop.hbase;</span>
<span class="source-line-no">019</span><span id="line-19"></span>
<span class="source-line-no">020</span><span id="line-20">import org.apache.hadoop.hbase.io.HeapSize;</span>
<span class="source-line-no">021</span><span id="line-21">import org.apache.yetus.audience.InterfaceAudience;</span>
<span class="source-line-no">022</span><span id="line-22"></span>
<span class="source-line-no">023</span><span id="line-23">/**</span>
<span class="source-line-no">024</span><span id="line-24"> * The unit of storage in HBase consisting of the following fields: &lt;br&gt;</span>
<span class="source-line-no">025</span><span id="line-25"> *</span>
<span class="source-line-no">026</span><span id="line-26"> * &lt;pre&gt;</span>
<span class="source-line-no">027</span><span id="line-27"> * 1) row</span>
<span class="source-line-no">028</span><span id="line-28"> * 2) column family</span>
<span class="source-line-no">029</span><span id="line-29"> * 3) column qualifier</span>
<span class="source-line-no">030</span><span id="line-30"> * 4) timestamp</span>
<span class="source-line-no">031</span><span id="line-31"> * 5) type</span>
<span class="source-line-no">032</span><span id="line-32"> * 6) MVCC version</span>
<span class="source-line-no">033</span><span id="line-33"> * 7) value</span>
<span class="source-line-no">034</span><span id="line-34"> * &lt;/pre&gt;</span>
<span class="source-line-no">035</span><span id="line-35"> * &lt;p&gt;</span>
<span class="source-line-no">036</span><span id="line-36"> * Uniqueness is determined by the combination of row, column family, column qualifier, timestamp,</span>
<span class="source-line-no">037</span><span id="line-37"> * and type.</span>
<span class="source-line-no">038</span><span id="line-38"> * &lt;/p&gt;</span>
<span class="source-line-no">039</span><span id="line-39"> * &lt;p&gt;</span>
<span class="source-line-no">040</span><span id="line-40"> * The natural comparator will perform a bitwise comparison on row, column family, and column</span>
<span class="source-line-no">041</span><span id="line-41"> * qualifier. Less intuitively, it will then treat the greater timestamp as the lesser value with</span>
<span class="source-line-no">042</span><span id="line-42"> * the goal of sorting newer cells first.</span>
<span class="source-line-no">043</span><span id="line-43"> * &lt;/p&gt;</span>
<span class="source-line-no">044</span><span id="line-44"> * &lt;p&gt;</span>
<span class="source-line-no">045</span><span id="line-45"> * Cell implements Comparable&amp;lt;Cell&amp;gt; which is only meaningful when comparing to other keys in</span>
<span class="source-line-no">046</span><span id="line-46"> * the same table. It uses CellComparator which does not work on the -ROOT- and hbase:meta tables.</span>
<span class="source-line-no">047</span><span id="line-47"> * &lt;/p&gt;</span>
<span class="source-line-no">048</span><span id="line-48"> * &lt;p&gt;</span>
<span class="source-line-no">049</span><span id="line-49"> * In the future, we may consider adding a boolean isOnHeap() method and a getValueBuffer() method</span>
<span class="source-line-no">050</span><span id="line-50"> * that can be used to pass a value directly from an off-heap ByteBuffer to the network without</span>
<span class="source-line-no">051</span><span id="line-51"> * copying into an on-heap byte[].</span>
<span class="source-line-no">052</span><span id="line-52"> * &lt;/p&gt;</span>
<span class="source-line-no">053</span><span id="line-53"> * &lt;p&gt;</span>
<span class="source-line-no">054</span><span id="line-54"> * Historic note: the original Cell implementation (KeyValue) requires that all fields be encoded as</span>
<span class="source-line-no">055</span><span id="line-55"> * consecutive bytes in the same byte[], whereas this interface allows fields to reside in separate</span>
<span class="source-line-no">056</span><span id="line-56"> * byte[]'s.</span>
<span class="source-line-no">057</span><span id="line-57"> * &lt;/p&gt;</span>
<span class="source-line-no">058</span><span id="line-58"> */</span>
<span class="source-line-no">059</span><span id="line-59">@InterfaceAudience.Public</span>
<span class="source-line-no">060</span><span id="line-60">public interface Cell extends HeapSize {</span>
<span class="source-line-no">061</span><span id="line-61"></span>
<span class="source-line-no">062</span><span id="line-62"> // 1) Row</span>
<span class="source-line-no">063</span><span id="line-63"></span>
<span class="source-line-no">064</span><span id="line-64"> /**</span>
<span class="source-line-no">065</span><span id="line-65"> * Contiguous raw bytes that may start at any index in the containing array. Max length is</span>
<span class="source-line-no">066</span><span id="line-66"> * Short.MAX_VALUE which is 32,767 bytes.</span>
<span class="source-line-no">067</span><span id="line-67"> * @return The array containing the row bytes.</span>
<span class="source-line-no">068</span><span id="line-68"> */</span>
<span class="source-line-no">069</span><span id="line-69"> byte[] getRowArray();</span>
<span class="source-line-no">070</span><span id="line-70"></span>
<span class="source-line-no">071</span><span id="line-71"> /** Returns Array index of first row byte */</span>
<span class="source-line-no">072</span><span id="line-72"> int getRowOffset();</span>
<span class="source-line-no">073</span><span id="line-73"></span>
<span class="source-line-no">074</span><span id="line-74"> /** Returns Number of row bytes. Must be &amp;lt; rowArray.length - offset. */</span>
<span class="source-line-no">075</span><span id="line-75"> short getRowLength();</span>
<span class="source-line-no">076</span><span id="line-76"></span>
<span class="source-line-no">077</span><span id="line-77"> // 2) Family</span>
<span class="source-line-no">078</span><span id="line-78"></span>
<span class="source-line-no">079</span><span id="line-79"> /**</span>
<span class="source-line-no">080</span><span id="line-80"> * Contiguous bytes composed of legal HDFS filename characters which may start at any index in the</span>
<span class="source-line-no">081</span><span id="line-81"> * containing array. Max length is Byte.MAX_VALUE, which is 127 bytes.</span>
<span class="source-line-no">082</span><span id="line-82"> * @return the array containing the family bytes.</span>
<span class="source-line-no">083</span><span id="line-83"> */</span>
<span class="source-line-no">084</span><span id="line-84"> byte[] getFamilyArray();</span>
<span class="source-line-no">085</span><span id="line-85"></span>
<span class="source-line-no">086</span><span id="line-86"> /** Returns Array index of first family byte */</span>
<span class="source-line-no">087</span><span id="line-87"> int getFamilyOffset();</span>
<span class="source-line-no">088</span><span id="line-88"></span>
<span class="source-line-no">089</span><span id="line-89"> /** Returns Number of family bytes. Must be &amp;lt; familyArray.length - offset. */</span>
<span class="source-line-no">090</span><span id="line-90"> byte getFamilyLength();</span>
<span class="source-line-no">091</span><span id="line-91"></span>
<span class="source-line-no">092</span><span id="line-92"> // 3) Qualifier</span>
<span class="source-line-no">093</span><span id="line-93"></span>
<span class="source-line-no">094</span><span id="line-94"> /**</span>
<span class="source-line-no">095</span><span id="line-95"> * Contiguous raw bytes that may start at any index in the containing array.</span>
<span class="source-line-no">096</span><span id="line-96"> * @return The array containing the qualifier bytes.</span>
<span class="source-line-no">097</span><span id="line-97"> */</span>
<span class="source-line-no">098</span><span id="line-98"> byte[] getQualifierArray();</span>
<span class="source-line-no">099</span><span id="line-99"></span>
<span class="source-line-no">100</span><span id="line-100"> /** Returns Array index of first qualifier byte */</span>
<span class="source-line-no">101</span><span id="line-101"> int getQualifierOffset();</span>
<span class="source-line-no">102</span><span id="line-102"></span>
<span class="source-line-no">103</span><span id="line-103"> /** Returns Number of qualifier bytes. Must be &amp;lt; qualifierArray.length - offset. */</span>
<span class="source-line-no">104</span><span id="line-104"> int getQualifierLength();</span>
<span class="source-line-no">105</span><span id="line-105"></span>
<span class="source-line-no">106</span><span id="line-106"> // 4) Timestamp</span>
<span class="source-line-no">107</span><span id="line-107"></span>
<span class="source-line-no">108</span><span id="line-108"> /**</span>
<span class="source-line-no">109</span><span id="line-109"> * Return a long value representing time at which this cell was "Put" into the row. Typically</span>
<span class="source-line-no">110</span><span id="line-110"> * represents the time of insertion, but can be any value from 0 to Long.MAX_VALUE.</span>
<span class="source-line-no">111</span><span id="line-111"> */</span>
<span class="source-line-no">112</span><span id="line-112"> long getTimestamp();</span>
<span class="source-line-no">113</span><span id="line-113"></span>
<span class="source-line-no">114</span><span id="line-114"> // 5) Type</span>
<span class="source-line-no">115</span><span id="line-115"></span>
<span class="source-line-no">116</span><span id="line-116"> /**</span>
<span class="source-line-no">117</span><span id="line-117"> * Returns the type of cell in a human readable format using {@link Type}.</span>
<span class="source-line-no">118</span><span id="line-118"> * &lt;p&gt;</span>
<span class="source-line-no">119</span><span id="line-119"> * Note : This does not expose the internal types of Cells like {@link KeyValue.Type#Maximum} and</span>
<span class="source-line-no">120</span><span id="line-120"> * {@link KeyValue.Type#Minimum}</span>
<span class="source-line-no">121</span><span id="line-121"> * @return The data type this cell: one of Put, Delete, etc</span>
<span class="source-line-no">122</span><span id="line-122"> */</span>
<span class="source-line-no">123</span><span id="line-123"> Type getType();</span>
<span class="source-line-no">124</span><span id="line-124"></span>
<span class="source-line-no">125</span><span id="line-125"> // 6) Value</span>
<span class="source-line-no">126</span><span id="line-126"></span>
<span class="source-line-no">127</span><span id="line-127"> /**</span>
<span class="source-line-no">128</span><span id="line-128"> * Contiguous raw bytes that may start at any index in the containing array. Max length is</span>
<span class="source-line-no">129</span><span id="line-129"> * Integer.MAX_VALUE which is 2,147,483,647 bytes.</span>
<span class="source-line-no">130</span><span id="line-130"> * @return The array containing the value bytes.</span>
<span class="source-line-no">131</span><span id="line-131"> */</span>
<span class="source-line-no">132</span><span id="line-132"> byte[] getValueArray();</span>
<span class="source-line-no">133</span><span id="line-133"></span>
<span class="source-line-no">134</span><span id="line-134"> /** Returns Array index of first value byte */</span>
<span class="source-line-no">135</span><span id="line-135"> int getValueOffset();</span>
<span class="source-line-no">136</span><span id="line-136"></span>
<span class="source-line-no">137</span><span id="line-137"> /** Returns Number of value bytes. Must be &amp;lt; valueArray.length - offset. */</span>
<span class="source-line-no">138</span><span id="line-138"> int getValueLength();</span>
<span class="source-line-no">139</span><span id="line-139"></span>
<span class="source-line-no">140</span><span id="line-140"> /** Returns Serialized size (defaults to include tag length if has some tags). */</span>
<span class="source-line-no">141</span><span id="line-141"> int getSerializedSize();</span>
<span class="source-line-no">142</span><span id="line-142"></span>
<span class="source-line-no">143</span><span id="line-143"> /**</span>
<span class="source-line-no">144</span><span id="line-144"> * The valid types for user to build the cell. Currently, This is subset of {@link KeyValue.Type}.</span>
<span class="source-line-no">145</span><span id="line-145"> */</span>
<span class="source-line-no">146</span><span id="line-146"> enum Type {</span>
<span class="source-line-no">147</span><span id="line-147"> Put((byte) 4),</span>
<span class="source-line-no">148</span><span id="line-148"></span>
<span class="source-line-no">149</span><span id="line-149"> Delete((byte) 8),</span>
<span class="source-line-no">150</span><span id="line-150"></span>
<span class="source-line-no">151</span><span id="line-151"> DeleteFamilyVersion((byte) 10),</span>
<span class="source-line-no">152</span><span id="line-152"></span>
<span class="source-line-no">153</span><span id="line-153"> DeleteColumn((byte) 12),</span>
<span class="source-line-no">154</span><span id="line-154"></span>
<span class="source-line-no">155</span><span id="line-155"> DeleteFamily((byte) 14);</span>
<span class="source-line-no">156</span><span id="line-156"></span>
<span class="source-line-no">157</span><span id="line-157"> private final byte code;</span>
<span class="source-line-no">158</span><span id="line-158"></span>
<span class="source-line-no">159</span><span id="line-159"> Type(final byte c) {</span>
<span class="source-line-no">160</span><span id="line-160"> this.code = c;</span>
<span class="source-line-no">161</span><span id="line-161"> }</span>
<span class="source-line-no">162</span><span id="line-162"></span>
<span class="source-line-no">163</span><span id="line-163"> public byte getCode() {</span>
<span class="source-line-no">164</span><span id="line-164"> return this.code;</span>
<span class="source-line-no">165</span><span id="line-165"> }</span>
<span class="source-line-no">166</span><span id="line-166"> }</span>
<span class="source-line-no">167</span><span id="line-167">}</span>
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