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<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<span class="sourceLineNo">003</span> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a>
<span class="sourceLineNo">004</span> * distributed with this work for additional information<a name="line.4"></a>
<span class="sourceLineNo">005</span> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a>
<span class="sourceLineNo">006</span> * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
<span class="sourceLineNo">007</span> * "License"); you may not use this file except in compliance<a name="line.7"></a>
<span class="sourceLineNo">008</span> * with the License. You may obtain a copy of the License at<a name="line.8"></a>
<span class="sourceLineNo">009</span> *<a name="line.9"></a>
<span class="sourceLineNo">010</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<span class="sourceLineNo">011</span> *<a name="line.11"></a>
<span class="sourceLineNo">012</span> * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
<span class="sourceLineNo">013</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
<span class="sourceLineNo">014</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
<span class="sourceLineNo">015</span> * See the License for the specific language governing permissions and<a name="line.15"></a>
<span class="sourceLineNo">016</span> * limitations under the License.<a name="line.16"></a>
<span class="sourceLineNo">017</span> */<a name="line.17"></a>
<span class="sourceLineNo">018</span><a name="line.18"></a>
<span class="sourceLineNo">019</span>package org.apache.hadoop.hbase;<a name="line.19"></a>
<span class="sourceLineNo">020</span><a name="line.20"></a>
<span class="sourceLineNo">021</span>import org.apache.hadoop.hbase.io.HeapSize;<a name="line.21"></a>
<span class="sourceLineNo">022</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.22"></a>
<span class="sourceLineNo">023</span><a name="line.23"></a>
<span class="sourceLineNo">024</span><a name="line.24"></a>
<span class="sourceLineNo">025</span>/**<a name="line.25"></a>
<span class="sourceLineNo">026</span> * The unit of storage in HBase consisting of the following fields:<a name="line.26"></a>
<span class="sourceLineNo">027</span> * &lt;br&gt;<a name="line.27"></a>
<span class="sourceLineNo">028</span> * &lt;pre&gt;<a name="line.28"></a>
<span class="sourceLineNo">029</span> * 1) row<a name="line.29"></a>
<span class="sourceLineNo">030</span> * 2) column family<a name="line.30"></a>
<span class="sourceLineNo">031</span> * 3) column qualifier<a name="line.31"></a>
<span class="sourceLineNo">032</span> * 4) timestamp<a name="line.32"></a>
<span class="sourceLineNo">033</span> * 5) type<a name="line.33"></a>
<span class="sourceLineNo">034</span> * 6) MVCC version<a name="line.34"></a>
<span class="sourceLineNo">035</span> * 7) value<a name="line.35"></a>
<span class="sourceLineNo">036</span> * &lt;/pre&gt;<a name="line.36"></a>
<span class="sourceLineNo">037</span> * &lt;p&gt;<a name="line.37"></a>
<span class="sourceLineNo">038</span> * Uniqueness is determined by the combination of row, column family, column qualifier,<a name="line.38"></a>
<span class="sourceLineNo">039</span> * timestamp, and type.<a name="line.39"></a>
<span class="sourceLineNo">040</span> * &lt;/p&gt;<a name="line.40"></a>
<span class="sourceLineNo">041</span> * &lt;p&gt;<a name="line.41"></a>
<span class="sourceLineNo">042</span> * The natural comparator will perform a bitwise comparison on row, column family, and column<a name="line.42"></a>
<span class="sourceLineNo">043</span> * qualifier. Less intuitively, it will then treat the greater timestamp as the lesser value with<a name="line.43"></a>
<span class="sourceLineNo">044</span> * the goal of sorting newer cells first.<a name="line.44"></a>
<span class="sourceLineNo">045</span> * &lt;/p&gt;<a name="line.45"></a>
<span class="sourceLineNo">046</span> * &lt;p&gt;<a name="line.46"></a>
<span class="sourceLineNo">047</span> * Cell implements Comparable&amp;lt;Cell&amp;gt; which is only meaningful when<a name="line.47"></a>
<span class="sourceLineNo">048</span> * comparing to other keys in the<a name="line.48"></a>
<span class="sourceLineNo">049</span> * same table. It uses CellComparator which does not work on the -ROOT- and hbase:meta tables.<a name="line.49"></a>
<span class="sourceLineNo">050</span> * &lt;/p&gt;<a name="line.50"></a>
<span class="sourceLineNo">051</span> * &lt;p&gt;<a name="line.51"></a>
<span class="sourceLineNo">052</span> * In the future, we may consider adding a boolean isOnHeap() method and a getValueBuffer() method<a name="line.52"></a>
<span class="sourceLineNo">053</span> * that can be used to pass a value directly from an off-heap ByteBuffer to the network without<a name="line.53"></a>
<span class="sourceLineNo">054</span> * copying into an on-heap byte[].<a name="line.54"></a>
<span class="sourceLineNo">055</span> * &lt;/p&gt;<a name="line.55"></a>
<span class="sourceLineNo">056</span> * &lt;p&gt;<a name="line.56"></a>
<span class="sourceLineNo">057</span> * Historic note: the original Cell implementation (KeyValue) requires that all fields be encoded as<a name="line.57"></a>
<span class="sourceLineNo">058</span> * consecutive bytes in the same byte[], whereas this interface allows fields to reside in separate<a name="line.58"></a>
<span class="sourceLineNo">059</span> * byte[]'s.<a name="line.59"></a>
<span class="sourceLineNo">060</span> * &lt;/p&gt;<a name="line.60"></a>
<span class="sourceLineNo">061</span> */<a name="line.61"></a>
<span class="sourceLineNo">062</span>@InterfaceAudience.Public<a name="line.62"></a>
<span class="sourceLineNo">063</span>public interface Cell extends HeapSize {<a name="line.63"></a>
<span class="sourceLineNo">064</span><a name="line.64"></a>
<span class="sourceLineNo">065</span> //1) Row<a name="line.65"></a>
<span class="sourceLineNo">066</span><a name="line.66"></a>
<span class="sourceLineNo">067</span> /**<a name="line.67"></a>
<span class="sourceLineNo">068</span> * Contiguous raw bytes that may start at any index in the containing array. Max length is<a name="line.68"></a>
<span class="sourceLineNo">069</span> * Short.MAX_VALUE which is 32,767 bytes.<a name="line.69"></a>
<span class="sourceLineNo">070</span> * @return The array containing the row bytes.<a name="line.70"></a>
<span class="sourceLineNo">071</span> */<a name="line.71"></a>
<span class="sourceLineNo">072</span> byte[] getRowArray();<a name="line.72"></a>
<span class="sourceLineNo">073</span><a name="line.73"></a>
<span class="sourceLineNo">074</span> /**<a name="line.74"></a>
<span class="sourceLineNo">075</span> * @return Array index of first row byte<a name="line.75"></a>
<span class="sourceLineNo">076</span> */<a name="line.76"></a>
<span class="sourceLineNo">077</span> int getRowOffset();<a name="line.77"></a>
<span class="sourceLineNo">078</span><a name="line.78"></a>
<span class="sourceLineNo">079</span> /**<a name="line.79"></a>
<span class="sourceLineNo">080</span> * @return Number of row bytes. Must be &amp;lt; rowArray.length - offset.<a name="line.80"></a>
<span class="sourceLineNo">081</span> */<a name="line.81"></a>
<span class="sourceLineNo">082</span> short getRowLength();<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> //2) Family<a name="line.85"></a>
<span class="sourceLineNo">086</span><a name="line.86"></a>
<span class="sourceLineNo">087</span> /**<a name="line.87"></a>
<span class="sourceLineNo">088</span> * Contiguous bytes composed of legal HDFS filename characters which may start at any index in the<a name="line.88"></a>
<span class="sourceLineNo">089</span> * containing array. Max length is Byte.MAX_VALUE, which is 127 bytes.<a name="line.89"></a>
<span class="sourceLineNo">090</span> * @return the array containing the family bytes.<a name="line.90"></a>
<span class="sourceLineNo">091</span> */<a name="line.91"></a>
<span class="sourceLineNo">092</span> byte[] getFamilyArray();<a name="line.92"></a>
<span class="sourceLineNo">093</span><a name="line.93"></a>
<span class="sourceLineNo">094</span> /**<a name="line.94"></a>
<span class="sourceLineNo">095</span> * @return Array index of first family byte<a name="line.95"></a>
<span class="sourceLineNo">096</span> */<a name="line.96"></a>
<span class="sourceLineNo">097</span> int getFamilyOffset();<a name="line.97"></a>
<span class="sourceLineNo">098</span><a name="line.98"></a>
<span class="sourceLineNo">099</span> /**<a name="line.99"></a>
<span class="sourceLineNo">100</span> * @return Number of family bytes. Must be &amp;lt; familyArray.length - offset.<a name="line.100"></a>
<span class="sourceLineNo">101</span> */<a name="line.101"></a>
<span class="sourceLineNo">102</span> byte getFamilyLength();<a name="line.102"></a>
<span class="sourceLineNo">103</span><a name="line.103"></a>
<span class="sourceLineNo">104</span><a name="line.104"></a>
<span class="sourceLineNo">105</span> //3) Qualifier<a name="line.105"></a>
<span class="sourceLineNo">106</span><a name="line.106"></a>
<span class="sourceLineNo">107</span> /**<a name="line.107"></a>
<span class="sourceLineNo">108</span> * Contiguous raw bytes that may start at any index in the containing array.<a name="line.108"></a>
<span class="sourceLineNo">109</span> * @return The array containing the qualifier bytes.<a name="line.109"></a>
<span class="sourceLineNo">110</span> */<a name="line.110"></a>
<span class="sourceLineNo">111</span> byte[] getQualifierArray();<a name="line.111"></a>
<span class="sourceLineNo">112</span><a name="line.112"></a>
<span class="sourceLineNo">113</span> /**<a name="line.113"></a>
<span class="sourceLineNo">114</span> * @return Array index of first qualifier byte<a name="line.114"></a>
<span class="sourceLineNo">115</span> */<a name="line.115"></a>
<span class="sourceLineNo">116</span> int getQualifierOffset();<a name="line.116"></a>
<span class="sourceLineNo">117</span><a name="line.117"></a>
<span class="sourceLineNo">118</span> /**<a name="line.118"></a>
<span class="sourceLineNo">119</span> * @return Number of qualifier bytes. Must be &amp;lt; qualifierArray.length - offset.<a name="line.119"></a>
<span class="sourceLineNo">120</span> */<a name="line.120"></a>
<span class="sourceLineNo">121</span> int getQualifierLength();<a name="line.121"></a>
<span class="sourceLineNo">122</span><a name="line.122"></a>
<span class="sourceLineNo">123</span><a name="line.123"></a>
<span class="sourceLineNo">124</span> //4) Timestamp<a name="line.124"></a>
<span class="sourceLineNo">125</span><a name="line.125"></a>
<span class="sourceLineNo">126</span> /**<a name="line.126"></a>
<span class="sourceLineNo">127</span> * @return Long value representing time at which this cell was "Put" into the row. Typically<a name="line.127"></a>
<span class="sourceLineNo">128</span> * represents the time of insertion, but can be any value from 0 to Long.MAX_VALUE.<a name="line.128"></a>
<span class="sourceLineNo">129</span> */<a name="line.129"></a>
<span class="sourceLineNo">130</span> long getTimestamp();<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>
<span class="sourceLineNo">133</span> //5) Type<a name="line.133"></a>
<span class="sourceLineNo">134</span><a name="line.134"></a>
<span class="sourceLineNo">135</span> /**<a name="line.135"></a>
<span class="sourceLineNo">136</span> * @return The byte representation of the KeyValue.TYPE of this cell: one of Put, Delete, etc<a name="line.136"></a>
<span class="sourceLineNo">137</span> * @deprecated As of HBase-2.0. Will be removed in HBase-3.0. Use {@link #getType()}.<a name="line.137"></a>
<span class="sourceLineNo">138</span> */<a name="line.138"></a>
<span class="sourceLineNo">139</span> @Deprecated<a name="line.139"></a>
<span class="sourceLineNo">140</span> byte getTypeByte();<a name="line.140"></a>
<span class="sourceLineNo">141</span><a name="line.141"></a>
<span class="sourceLineNo">142</span><a name="line.142"></a>
<span class="sourceLineNo">143</span> //6) SequenceId<a name="line.143"></a>
<span class="sourceLineNo">144</span><a name="line.144"></a>
<span class="sourceLineNo">145</span> /**<a name="line.145"></a>
<span class="sourceLineNo">146</span> * A region-specific unique monotonically increasing sequence ID given to each Cell. It always<a name="line.146"></a>
<span class="sourceLineNo">147</span> * exists for cells in the memstore but is not retained forever. It will be kept for<a name="line.147"></a>
<span class="sourceLineNo">148</span> * {@link HConstants#KEEP_SEQID_PERIOD} days, but generally becomes irrelevant after the cell's<a name="line.148"></a>
<span class="sourceLineNo">149</span> * row is no longer involved in any operations that require strict consistency.<a name="line.149"></a>
<span class="sourceLineNo">150</span> * @return seqId (always &amp;gt; 0 if exists), or 0 if it no longer exists<a name="line.150"></a>
<span class="sourceLineNo">151</span> * @deprecated As of HBase-2.0. Will be removed in HBase-3.0.<a name="line.151"></a>
<span class="sourceLineNo">152</span> */<a name="line.152"></a>
<span class="sourceLineNo">153</span> @Deprecated<a name="line.153"></a>
<span class="sourceLineNo">154</span> long getSequenceId();<a name="line.154"></a>
<span class="sourceLineNo">155</span><a name="line.155"></a>
<span class="sourceLineNo">156</span> //7) Value<a name="line.156"></a>
<span class="sourceLineNo">157</span><a name="line.157"></a>
<span class="sourceLineNo">158</span> /**<a name="line.158"></a>
<span class="sourceLineNo">159</span> * Contiguous raw bytes that may start at any index in the containing array. Max length is<a name="line.159"></a>
<span class="sourceLineNo">160</span> * Integer.MAX_VALUE which is 2,147,483,647 bytes.<a name="line.160"></a>
<span class="sourceLineNo">161</span> * @return The array containing the value bytes.<a name="line.161"></a>
<span class="sourceLineNo">162</span> */<a name="line.162"></a>
<span class="sourceLineNo">163</span> byte[] getValueArray();<a name="line.163"></a>
<span class="sourceLineNo">164</span><a name="line.164"></a>
<span class="sourceLineNo">165</span> /**<a name="line.165"></a>
<span class="sourceLineNo">166</span> * @return Array index of first value byte<a name="line.166"></a>
<span class="sourceLineNo">167</span> */<a name="line.167"></a>
<span class="sourceLineNo">168</span> int getValueOffset();<a name="line.168"></a>
<span class="sourceLineNo">169</span><a name="line.169"></a>
<span class="sourceLineNo">170</span> /**<a name="line.170"></a>
<span class="sourceLineNo">171</span> * @return Number of value bytes. Must be &amp;lt; valueArray.length - offset.<a name="line.171"></a>
<span class="sourceLineNo">172</span> */<a name="line.172"></a>
<span class="sourceLineNo">173</span> int getValueLength();<a name="line.173"></a>
<span class="sourceLineNo">174</span><a name="line.174"></a>
<span class="sourceLineNo">175</span> /**<a name="line.175"></a>
<span class="sourceLineNo">176</span> * @return Serialized size (defaults to include tag length if has some tags).<a name="line.176"></a>
<span class="sourceLineNo">177</span> */<a name="line.177"></a>
<span class="sourceLineNo">178</span> int getSerializedSize();<a name="line.178"></a>
<span class="sourceLineNo">179</span><a name="line.179"></a>
<span class="sourceLineNo">180</span> /**<a name="line.180"></a>
<span class="sourceLineNo">181</span> * Contiguous raw bytes representing tags that may start at any index in the containing array.<a name="line.181"></a>
<span class="sourceLineNo">182</span> * @return the tags byte array<a name="line.182"></a>
<span class="sourceLineNo">183</span> * @deprecated As of HBase-2.0. Will be removed in HBase-3.0. Tags are are now internal.<a name="line.183"></a>
<span class="sourceLineNo">184</span> */<a name="line.184"></a>
<span class="sourceLineNo">185</span> @Deprecated<a name="line.185"></a>
<span class="sourceLineNo">186</span> byte[] getTagsArray();<a name="line.186"></a>
<span class="sourceLineNo">187</span><a name="line.187"></a>
<span class="sourceLineNo">188</span> /**<a name="line.188"></a>
<span class="sourceLineNo">189</span> * @return the first offset where the tags start in the Cell<a name="line.189"></a>
<span class="sourceLineNo">190</span> * @deprecated As of HBase-2.0. Will be removed in HBase-3.0. Tags are are now internal.<a name="line.190"></a>
<span class="sourceLineNo">191</span> */<a name="line.191"></a>
<span class="sourceLineNo">192</span> @Deprecated<a name="line.192"></a>
<span class="sourceLineNo">193</span> int getTagsOffset();<a name="line.193"></a>
<span class="sourceLineNo">194</span><a name="line.194"></a>
<span class="sourceLineNo">195</span> /**<a name="line.195"></a>
<span class="sourceLineNo">196</span> * HBase internally uses 2 bytes to store tags length in Cell.<a name="line.196"></a>
<span class="sourceLineNo">197</span> * As the tags length is always a non-negative number, to make good use of the sign bit,<a name="line.197"></a>
<span class="sourceLineNo">198</span> * the max of tags length is defined 2 * Short.MAX_VALUE + 1 = 65535.<a name="line.198"></a>
<span class="sourceLineNo">199</span> * As a result, the return type is int, because a short is not capable of handling that.<a name="line.199"></a>
<span class="sourceLineNo">200</span> * Please note that even if the return type is int, the max tags length is far<a name="line.200"></a>
<span class="sourceLineNo">201</span> * less than Integer.MAX_VALUE.<a name="line.201"></a>
<span class="sourceLineNo">202</span> *<a name="line.202"></a>
<span class="sourceLineNo">203</span> * @return the total length of the tags in the Cell.<a name="line.203"></a>
<span class="sourceLineNo">204</span> * @deprecated As of HBase-2.0. Will be removed in HBase-3.0. Tags are are now internal.<a name="line.204"></a>
<span class="sourceLineNo">205</span> */<a name="line.205"></a>
<span class="sourceLineNo">206</span> @Deprecated<a name="line.206"></a>
<span class="sourceLineNo">207</span> int getTagsLength();<a name="line.207"></a>
<span class="sourceLineNo">208</span><a name="line.208"></a>
<span class="sourceLineNo">209</span> /**<a name="line.209"></a>
<span class="sourceLineNo">210</span> * Returns the type of cell in a human readable format using {@link Type}.<a name="line.210"></a>
<span class="sourceLineNo">211</span> * Note : This does not expose the internal types of Cells like {@link KeyValue.Type#Maximum} and<a name="line.211"></a>
<span class="sourceLineNo">212</span> * {@link KeyValue.Type#Minimum}<a name="line.212"></a>
<span class="sourceLineNo">213</span> * @return The data type this cell: one of Put, Delete, etc<a name="line.213"></a>
<span class="sourceLineNo">214</span> */<a name="line.214"></a>
<span class="sourceLineNo">215</span> default Type getType() {<a name="line.215"></a>
<span class="sourceLineNo">216</span> byte byteType = getTypeByte();<a name="line.216"></a>
<span class="sourceLineNo">217</span> Type t = Type.CODE_ARRAY[byteType &amp; 0xff];<a name="line.217"></a>
<span class="sourceLineNo">218</span> if (t != null) {<a name="line.218"></a>
<span class="sourceLineNo">219</span> return t;<a name="line.219"></a>
<span class="sourceLineNo">220</span> }<a name="line.220"></a>
<span class="sourceLineNo">221</span> throw new UnsupportedOperationException("Invalid type of cell " + byteType);<a name="line.221"></a>
<span class="sourceLineNo">222</span> }<a name="line.222"></a>
<span class="sourceLineNo">223</span><a name="line.223"></a>
<span class="sourceLineNo">224</span> /**<a name="line.224"></a>
<span class="sourceLineNo">225</span> * The valid types for user to build the cell. Currently, This is subset of {@link KeyValue.Type}.<a name="line.225"></a>
<span class="sourceLineNo">226</span> */<a name="line.226"></a>
<span class="sourceLineNo">227</span> enum Type {<a name="line.227"></a>
<span class="sourceLineNo">228</span> Put((byte) 4),<a name="line.228"></a>
<span class="sourceLineNo">229</span><a name="line.229"></a>
<span class="sourceLineNo">230</span> Delete((byte) 8),<a name="line.230"></a>
<span class="sourceLineNo">231</span><a name="line.231"></a>
<span class="sourceLineNo">232</span> DeleteFamilyVersion((byte) 10),<a name="line.232"></a>
<span class="sourceLineNo">233</span><a name="line.233"></a>
<span class="sourceLineNo">234</span> DeleteColumn((byte) 12),<a name="line.234"></a>
<span class="sourceLineNo">235</span><a name="line.235"></a>
<span class="sourceLineNo">236</span> DeleteFamily((byte) 14);<a name="line.236"></a>
<span class="sourceLineNo">237</span><a name="line.237"></a>
<span class="sourceLineNo">238</span> private final byte code;<a name="line.238"></a>
<span class="sourceLineNo">239</span><a name="line.239"></a>
<span class="sourceLineNo">240</span> Type(final byte c) {<a name="line.240"></a>
<span class="sourceLineNo">241</span> this.code = c;<a name="line.241"></a>
<span class="sourceLineNo">242</span> }<a name="line.242"></a>
<span class="sourceLineNo">243</span><a name="line.243"></a>
<span class="sourceLineNo">244</span> public byte getCode() {<a name="line.244"></a>
<span class="sourceLineNo">245</span> return this.code;<a name="line.245"></a>
<span class="sourceLineNo">246</span> }<a name="line.246"></a>
<span class="sourceLineNo">247</span><a name="line.247"></a>
<span class="sourceLineNo">248</span> private static final Type[] CODE_ARRAY = new Type[256];<a name="line.248"></a>
<span class="sourceLineNo">249</span><a name="line.249"></a>
<span class="sourceLineNo">250</span> static {<a name="line.250"></a>
<span class="sourceLineNo">251</span> for (Type t : Type.values()) {<a name="line.251"></a>
<span class="sourceLineNo">252</span> CODE_ARRAY[t.code &amp; 0xff] = t;<a name="line.252"></a>
<span class="sourceLineNo">253</span> }<a name="line.253"></a>
<span class="sourceLineNo">254</span> }<a name="line.254"></a>
<span class="sourceLineNo">255</span> }<a name="line.255"></a>
<span class="sourceLineNo">256</span>}<a name="line.256"></a>
</pre>
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