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<pre><span class="sourceLineNo">001</span>/**<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Copyright The Apache Software Foundation<a name="line.2"></a>
<span class="sourceLineNo">003</span> *<a name="line.3"></a>
<span class="sourceLineNo">004</span> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.4"></a>
<span class="sourceLineNo">005</span> * or more contributor license agreements. See the NOTICE file<a name="line.5"></a>
<span class="sourceLineNo">006</span> * distributed with this work for additional information<a name="line.6"></a>
<span class="sourceLineNo">007</span> * regarding copyright ownership. The ASF licenses this file<a name="line.7"></a>
<span class="sourceLineNo">008</span> * to you under the Apache License, Version 2.0 (the<a name="line.8"></a>
<span class="sourceLineNo">009</span> * "License"); you may not use this file except in compliance<a name="line.9"></a>
<span class="sourceLineNo">010</span> * with the License. You may obtain a copy of the License at<a name="line.10"></a>
<span class="sourceLineNo">011</span> *<a name="line.11"></a>
<span class="sourceLineNo">012</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.12"></a>
<span class="sourceLineNo">013</span> *<a name="line.13"></a>
<span class="sourceLineNo">014</span> * Unless required by applicable law or agreed to in writing, software<a name="line.14"></a>
<span class="sourceLineNo">015</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.15"></a>
<span class="sourceLineNo">016</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.16"></a>
<span class="sourceLineNo">017</span> * See the License for the specific language governing permissions and<a name="line.17"></a>
<span class="sourceLineNo">018</span> * limitations under the License.<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;<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.util.Bytes;<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.yetus.audience.InterfaceStability;<a name="line.26"></a>
<span class="sourceLineNo">027</span><a name="line.27"></a>
<span class="sourceLineNo">028</span>/**<a name="line.28"></a>
<span class="sourceLineNo">029</span> * This is a {@link Tag} implementation in which value is backed by an on heap byte array.<a name="line.29"></a>
<span class="sourceLineNo">030</span> */<a name="line.30"></a>
<span class="sourceLineNo">031</span>@InterfaceAudience.Private<a name="line.31"></a>
<span class="sourceLineNo">032</span>@InterfaceStability.Evolving<a name="line.32"></a>
<span class="sourceLineNo">033</span>public class ArrayBackedTag implements Tag {<a name="line.33"></a>
<span class="sourceLineNo">034</span> private final byte type;// TODO extra type state needed?<a name="line.34"></a>
<span class="sourceLineNo">035</span> private final byte[] bytes;<a name="line.35"></a>
<span class="sourceLineNo">036</span> private int offset = 0;<a name="line.36"></a>
<span class="sourceLineNo">037</span> private int length = 0;<a name="line.37"></a>
<span class="sourceLineNo">038</span><a name="line.38"></a>
<span class="sourceLineNo">039</span> /**<a name="line.39"></a>
<span class="sourceLineNo">040</span> * The special tag will write the length of each tag and that will be<a name="line.40"></a>
<span class="sourceLineNo">041</span> * followed by the type and then the actual tag.<a name="line.41"></a>
<span class="sourceLineNo">042</span> * So every time the length part is parsed we need to add + 1 byte to it to<a name="line.42"></a>
<span class="sourceLineNo">043</span> * get the type and then get the actual tag.<a name="line.43"></a>
<span class="sourceLineNo">044</span> */<a name="line.44"></a>
<span class="sourceLineNo">045</span> public ArrayBackedTag(byte tagType, String tag) {<a name="line.45"></a>
<span class="sourceLineNo">046</span> this(tagType, Bytes.toBytes(tag));<a name="line.46"></a>
<span class="sourceLineNo">047</span> }<a name="line.47"></a>
<span class="sourceLineNo">048</span><a name="line.48"></a>
<span class="sourceLineNo">049</span> /**<a name="line.49"></a>
<span class="sourceLineNo">050</span> * Format for a tag :<a name="line.50"></a>
<span class="sourceLineNo">051</span> * {@code &lt;length of tag - 2 bytes&gt;&lt;type code - 1 byte&gt;&lt;tag&gt;} tag length is serialized<a name="line.51"></a>
<span class="sourceLineNo">052</span> * using 2 bytes only but as this will be unsigned, we can have max tag length of<a name="line.52"></a>
<span class="sourceLineNo">053</span> * (Short.MAX_SIZE * 2) +1. It includes 1 byte type length and actual tag bytes length.<a name="line.53"></a>
<span class="sourceLineNo">054</span> */<a name="line.54"></a>
<span class="sourceLineNo">055</span> public ArrayBackedTag(byte tagType, byte[] tag) {<a name="line.55"></a>
<span class="sourceLineNo">056</span> int tagLength = tag.length + TYPE_LENGTH_SIZE;<a name="line.56"></a>
<span class="sourceLineNo">057</span> if (tagLength &gt; MAX_TAG_LENGTH) {<a name="line.57"></a>
<span class="sourceLineNo">058</span> throw new IllegalArgumentException(<a name="line.58"></a>
<span class="sourceLineNo">059</span> "Invalid tag data being passed. Its length can not exceed " + MAX_TAG_LENGTH);<a name="line.59"></a>
<span class="sourceLineNo">060</span> }<a name="line.60"></a>
<span class="sourceLineNo">061</span> length = TAG_LENGTH_SIZE + tagLength;<a name="line.61"></a>
<span class="sourceLineNo">062</span> bytes = new byte[length];<a name="line.62"></a>
<span class="sourceLineNo">063</span> int pos = Bytes.putAsShort(bytes, 0, tagLength);<a name="line.63"></a>
<span class="sourceLineNo">064</span> pos = Bytes.putByte(bytes, pos, tagType);<a name="line.64"></a>
<span class="sourceLineNo">065</span> Bytes.putBytes(bytes, pos, tag, 0, tag.length);<a name="line.65"></a>
<span class="sourceLineNo">066</span> this.type = tagType;<a name="line.66"></a>
<span class="sourceLineNo">067</span> }<a name="line.67"></a>
<span class="sourceLineNo">068</span><a name="line.68"></a>
<span class="sourceLineNo">069</span> /**<a name="line.69"></a>
<span class="sourceLineNo">070</span> * Creates a Tag from the specified byte array and offset. Presumes<a name="line.70"></a>
<span class="sourceLineNo">071</span> * &lt;code&gt;bytes&lt;/code&gt; content starting at &lt;code&gt;offset&lt;/code&gt; is formatted as<a name="line.71"></a>
<span class="sourceLineNo">072</span> * a Tag blob.<a name="line.72"></a>
<span class="sourceLineNo">073</span> * The bytes to include the tag type, tag length and actual tag bytes.<a name="line.73"></a>
<span class="sourceLineNo">074</span> * @param offset offset to start of Tag<a name="line.74"></a>
<span class="sourceLineNo">075</span> */<a name="line.75"></a>
<span class="sourceLineNo">076</span> public ArrayBackedTag(byte[] bytes, int offset) {<a name="line.76"></a>
<span class="sourceLineNo">077</span> this(bytes, offset, getLength(bytes, offset));<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> private static int getLength(byte[] bytes, int offset) {<a name="line.80"></a>
<span class="sourceLineNo">081</span> return TAG_LENGTH_SIZE + Bytes.readAsInt(bytes, offset, TAG_LENGTH_SIZE);<a name="line.81"></a>
<span class="sourceLineNo">082</span> }<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> * Creates a Tag from the specified byte array, starting at offset, and for length<a name="line.85"></a>
<span class="sourceLineNo">086</span> * &lt;code&gt;length&lt;/code&gt;. Presumes &lt;code&gt;bytes&lt;/code&gt; content starting at &lt;code&gt;offset&lt;/code&gt; is<a name="line.86"></a>
<span class="sourceLineNo">087</span> * formatted as a Tag blob.<a name="line.87"></a>
<span class="sourceLineNo">088</span> */<a name="line.88"></a>
<span class="sourceLineNo">089</span> public ArrayBackedTag(byte[] bytes, int offset, int length) {<a name="line.89"></a>
<span class="sourceLineNo">090</span> if (length &gt; MAX_TAG_LENGTH) {<a name="line.90"></a>
<span class="sourceLineNo">091</span> throw new IllegalArgumentException(<a name="line.91"></a>
<span class="sourceLineNo">092</span> "Invalid tag data being passed. Its length can not exceed " + MAX_TAG_LENGTH);<a name="line.92"></a>
<span class="sourceLineNo">093</span> }<a name="line.93"></a>
<span class="sourceLineNo">094</span> this.bytes = bytes;<a name="line.94"></a>
<span class="sourceLineNo">095</span> this.offset = offset;<a name="line.95"></a>
<span class="sourceLineNo">096</span> this.length = length;<a name="line.96"></a>
<span class="sourceLineNo">097</span> this.type = bytes[offset + TAG_LENGTH_SIZE];<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> /**<a name="line.100"></a>
<span class="sourceLineNo">101</span> * @return The byte array backing this Tag.<a name="line.101"></a>
<span class="sourceLineNo">102</span> */<a name="line.102"></a>
<span class="sourceLineNo">103</span> @Override<a name="line.103"></a>
<span class="sourceLineNo">104</span> public byte[] getValueArray() {<a name="line.104"></a>
<span class="sourceLineNo">105</span> return this.bytes;<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> /**<a name="line.108"></a>
<span class="sourceLineNo">109</span> * @return the tag type<a name="line.109"></a>
<span class="sourceLineNo">110</span> */<a name="line.110"></a>
<span class="sourceLineNo">111</span> @Override<a name="line.111"></a>
<span class="sourceLineNo">112</span> public byte getType() {<a name="line.112"></a>
<span class="sourceLineNo">113</span> return this.type;<a name="line.113"></a>
<span class="sourceLineNo">114</span> }<a name="line.114"></a>
<span class="sourceLineNo">115</span><a name="line.115"></a>
<span class="sourceLineNo">116</span> /**<a name="line.116"></a>
<span class="sourceLineNo">117</span> * @return Length of actual tag bytes within the backed buffer<a name="line.117"></a>
<span class="sourceLineNo">118</span> */<a name="line.118"></a>
<span class="sourceLineNo">119</span> @Override<a name="line.119"></a>
<span class="sourceLineNo">120</span> public int getValueLength() {<a name="line.120"></a>
<span class="sourceLineNo">121</span> return this.length - INFRASTRUCTURE_SIZE;<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> /**<a name="line.124"></a>
<span class="sourceLineNo">125</span> * @return Offset of actual tag bytes within the backed buffer<a name="line.125"></a>
<span class="sourceLineNo">126</span> */<a name="line.126"></a>
<span class="sourceLineNo">127</span> @Override<a name="line.127"></a>
<span class="sourceLineNo">128</span> public int getValueOffset() {<a name="line.128"></a>
<span class="sourceLineNo">129</span> return this.offset + INFRASTRUCTURE_SIZE;<a name="line.129"></a>
<span class="sourceLineNo">130</span> }<a name="line.130"></a>
<span class="sourceLineNo">131</span><a name="line.131"></a>
<span class="sourceLineNo">132</span> @Override<a name="line.132"></a>
<span class="sourceLineNo">133</span> public boolean hasArray() {<a name="line.133"></a>
<span class="sourceLineNo">134</span> return true;<a name="line.134"></a>
<span class="sourceLineNo">135</span> }<a name="line.135"></a>
<span class="sourceLineNo">136</span><a name="line.136"></a>
<span class="sourceLineNo">137</span> @Override<a name="line.137"></a>
<span class="sourceLineNo">138</span> public ByteBuffer getValueByteBuffer() {<a name="line.138"></a>
<span class="sourceLineNo">139</span> return ByteBuffer.wrap(bytes);<a name="line.139"></a>
<span class="sourceLineNo">140</span> }<a name="line.140"></a>
<span class="sourceLineNo">141</span><a name="line.141"></a>
<span class="sourceLineNo">142</span> @Override<a name="line.142"></a>
<span class="sourceLineNo">143</span> public String toString() {<a name="line.143"></a>
<span class="sourceLineNo">144</span> return "[Tag type : " + this.type + ", value : "<a name="line.144"></a>
<span class="sourceLineNo">145</span> + Bytes.toStringBinary(bytes, getValueOffset(), getValueLength()) + "]";<a name="line.145"></a>
<span class="sourceLineNo">146</span> }<a name="line.146"></a>
<span class="sourceLineNo">147</span>}<a name="line.147"></a>
</pre>
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