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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>package org.apache.hadoop.hbase.client;<a name="line.18"></a>
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>import java.io.Closeable;<a name="line.20"></a>
<span class="sourceLineNo">021</span>import java.io.IOException;<a name="line.21"></a>
<span class="sourceLineNo">022</span>import java.util.concurrent.ExecutorService;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import org.apache.hadoop.conf.Configuration;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import org.apache.hadoop.hbase.Abortable;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import org.apache.hadoop.hbase.HBaseInterfaceAudience;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import org.apache.hadoop.hbase.ServerName;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import org.apache.hadoop.hbase.TableName;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import org.apache.hadoop.hbase.util.FutureUtils;<a name="line.28"></a>
<span class="sourceLineNo">029</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.29"></a>
<span class="sourceLineNo">030</span><a name="line.30"></a>
<span class="sourceLineNo">031</span>/**<a name="line.31"></a>
<span class="sourceLineNo">032</span> * A cluster connection encapsulating lower level individual connections to actual servers and a<a name="line.32"></a>
<span class="sourceLineNo">033</span> * connection to zookeeper. Connections are instantiated through the {@link ConnectionFactory}<a name="line.33"></a>
<span class="sourceLineNo">034</span> * class. The lifecycle of the connection is managed by the caller, who has to {@link #close()} the<a name="line.34"></a>
<span class="sourceLineNo">035</span> * connection to release the resources.<a name="line.35"></a>
<span class="sourceLineNo">036</span> * &lt;p&gt;<a name="line.36"></a>
<span class="sourceLineNo">037</span> * The connection object contains logic to find the master, locate regions out on the cluster, keeps<a name="line.37"></a>
<span class="sourceLineNo">038</span> * a cache of locations and then knows how to re-calibrate after they move. The individual<a name="line.38"></a>
<span class="sourceLineNo">039</span> * connections to servers, meta cache, zookeeper connection, etc are all shared by the {@link Table}<a name="line.39"></a>
<span class="sourceLineNo">040</span> * and {@link Admin} instances obtained from this connection.<a name="line.40"></a>
<span class="sourceLineNo">041</span> * &lt;p&gt;<a name="line.41"></a>
<span class="sourceLineNo">042</span> * Connection creation is a heavy-weight operation. Connection implementations are thread-safe, so<a name="line.42"></a>
<span class="sourceLineNo">043</span> * that the client can create a connection once, and share it with different threads. {@link Table}<a name="line.43"></a>
<span class="sourceLineNo">044</span> * and {@link Admin} instances, on the other hand, are light-weight and are not thread-safe.<a name="line.44"></a>
<span class="sourceLineNo">045</span> * Typically, a single connection per client application is instantiated and every thread will<a name="line.45"></a>
<span class="sourceLineNo">046</span> * obtain its own Table instance. Caching or pooling of {@link Table} and {@link Admin} is not<a name="line.46"></a>
<span class="sourceLineNo">047</span> * recommended.<a name="line.47"></a>
<span class="sourceLineNo">048</span> * @see ConnectionFactory<a name="line.48"></a>
<span class="sourceLineNo">049</span> * @since 0.99.0<a name="line.49"></a>
<span class="sourceLineNo">050</span> */<a name="line.50"></a>
<span class="sourceLineNo">051</span>@InterfaceAudience.Public<a name="line.51"></a>
<span class="sourceLineNo">052</span>public interface Connection extends Abortable, Closeable {<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> * Implementation notes: - Only allow new style of interfaces: -- All table names are passed as<a name="line.55"></a>
<span class="sourceLineNo">056</span> * TableName. No more byte[] and string arguments -- Most of the classes with names H is<a name="line.56"></a>
<span class="sourceLineNo">057</span> * deprecated in favor of non-H versions (Table, Connection, etc) -- Only real client-facing<a name="line.57"></a>
<span class="sourceLineNo">058</span> * public methods are allowed - Connection should contain only getTable(), getAdmin() kind of<a name="line.58"></a>
<span class="sourceLineNo">059</span> * general methods.<a name="line.59"></a>
<span class="sourceLineNo">060</span> */<a name="line.60"></a>
<span class="sourceLineNo">061</span><a name="line.61"></a>
<span class="sourceLineNo">062</span> /** Returns Configuration instance being used by this Connection instance. */<a name="line.62"></a>
<span class="sourceLineNo">063</span> Configuration getConfiguration();<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> * Retrieve a Table implementation for accessing a table. The returned Table is not thread safe, a<a name="line.66"></a>
<span class="sourceLineNo">067</span> * new instance should be created for each using thread. This is a lightweight operation, pooling<a name="line.67"></a>
<span class="sourceLineNo">068</span> * or caching of the returned Table is neither required nor desired.<a name="line.68"></a>
<span class="sourceLineNo">069</span> * &lt;p&gt;<a name="line.69"></a>
<span class="sourceLineNo">070</span> * The caller is responsible for calling {@link Table#close()} on the returned table instance.<a name="line.70"></a>
<span class="sourceLineNo">071</span> * &lt;p&gt;<a name="line.71"></a>
<span class="sourceLineNo">072</span> * Since 0.98.1 this method no longer checks table existence. An exception will be thrown if the<a name="line.72"></a>
<span class="sourceLineNo">073</span> * table does not exist only when the first operation is attempted.<a name="line.73"></a>
<span class="sourceLineNo">074</span> * @param tableName the name of the table<a name="line.74"></a>
<span class="sourceLineNo">075</span> * @return a Table to use for interactions with this table<a name="line.75"></a>
<span class="sourceLineNo">076</span> */<a name="line.76"></a>
<span class="sourceLineNo">077</span> default Table getTable(TableName tableName) throws IOException {<a name="line.77"></a>
<span class="sourceLineNo">078</span> return getTable(tableName, null);<a name="line.78"></a>
<span class="sourceLineNo">079</span> }<a name="line.79"></a>
<span class="sourceLineNo">080</span><a name="line.80"></a>
<span class="sourceLineNo">081</span> /**<a name="line.81"></a>
<span class="sourceLineNo">082</span> * Retrieve a Table implementation for accessing a table. The returned Table is not thread safe, a<a name="line.82"></a>
<span class="sourceLineNo">083</span> * new instance should be created for each using thread. This is a lightweight operation, pooling<a name="line.83"></a>
<span class="sourceLineNo">084</span> * or caching of the returned Table is neither required nor desired.<a name="line.84"></a>
<span class="sourceLineNo">085</span> * &lt;p&gt;<a name="line.85"></a>
<span class="sourceLineNo">086</span> * The caller is responsible for calling {@link Table#close()} on the returned table instance.<a name="line.86"></a>
<span class="sourceLineNo">087</span> * &lt;p&gt;<a name="line.87"></a>
<span class="sourceLineNo">088</span> * Since 0.98.1 this method no longer checks table existence. An exception will be thrown if the<a name="line.88"></a>
<span class="sourceLineNo">089</span> * table does not exist only when the first operation is attempted.<a name="line.89"></a>
<span class="sourceLineNo">090</span> * @param tableName the name of the table<a name="line.90"></a>
<span class="sourceLineNo">091</span> * @param pool The thread pool to use for batch operations, null to use a default pool.<a name="line.91"></a>
<span class="sourceLineNo">092</span> * @return a Table to use for interactions with this table<a name="line.92"></a>
<span class="sourceLineNo">093</span> */<a name="line.93"></a>
<span class="sourceLineNo">094</span> default Table getTable(TableName tableName, ExecutorService pool) throws IOException {<a name="line.94"></a>
<span class="sourceLineNo">095</span> return getTableBuilder(tableName, pool).build();<a name="line.95"></a>
<span class="sourceLineNo">096</span> }<a name="line.96"></a>
<span class="sourceLineNo">097</span><a name="line.97"></a>
<span class="sourceLineNo">098</span> /**<a name="line.98"></a>
<span class="sourceLineNo">099</span> * &lt;p&gt;<a name="line.99"></a>
<span class="sourceLineNo">100</span> * Retrieve a {@link BufferedMutator} for performing client-side buffering of writes. The<a name="line.100"></a>
<span class="sourceLineNo">101</span> * {@link BufferedMutator} returned by this method is thread-safe. This BufferedMutator will use<a name="line.101"></a>
<span class="sourceLineNo">102</span> * the Connection's ExecutorService. This object can be used for long lived operations.<a name="line.102"></a>
<span class="sourceLineNo">103</span> * &lt;/p&gt;<a name="line.103"></a>
<span class="sourceLineNo">104</span> * &lt;p&gt;<a name="line.104"></a>
<span class="sourceLineNo">105</span> * The caller is responsible for calling {@link BufferedMutator#close()} on the returned<a name="line.105"></a>
<span class="sourceLineNo">106</span> * {@link BufferedMutator} instance.<a name="line.106"></a>
<span class="sourceLineNo">107</span> * &lt;/p&gt;<a name="line.107"></a>
<span class="sourceLineNo">108</span> * &lt;p&gt;<a name="line.108"></a>
<span class="sourceLineNo">109</span> * This accessor will use the connection's ExecutorService and will throw an exception in the main<a name="line.109"></a>
<span class="sourceLineNo">110</span> * thread when an asynchronous exception occurs.<a name="line.110"></a>
<span class="sourceLineNo">111</span> * @param tableName the name of the table<a name="line.111"></a>
<span class="sourceLineNo">112</span> * @return a {@link BufferedMutator} for the supplied tableName.<a name="line.112"></a>
<span class="sourceLineNo">113</span> */<a name="line.113"></a>
<span class="sourceLineNo">114</span> default BufferedMutator getBufferedMutator(TableName tableName) throws IOException {<a name="line.114"></a>
<span class="sourceLineNo">115</span> return getBufferedMutator(new BufferedMutatorParams(tableName));<a name="line.115"></a>
<span class="sourceLineNo">116</span> }<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> * Retrieve a {@link BufferedMutator} for performing client-side buffering of writes. The<a name="line.119"></a>
<span class="sourceLineNo">120</span> * {@link BufferedMutator} returned by this method is thread-safe. This object can be used for<a name="line.120"></a>
<span class="sourceLineNo">121</span> * long lived table operations. The caller is responsible for calling<a name="line.121"></a>
<span class="sourceLineNo">122</span> * {@link BufferedMutator#close()} on the returned {@link BufferedMutator} instance.<a name="line.122"></a>
<span class="sourceLineNo">123</span> * @param params details on how to instantiate the {@code BufferedMutator}.<a name="line.123"></a>
<span class="sourceLineNo">124</span> * @return a {@link BufferedMutator} for the supplied tableName.<a name="line.124"></a>
<span class="sourceLineNo">125</span> */<a name="line.125"></a>
<span class="sourceLineNo">126</span> BufferedMutator getBufferedMutator(BufferedMutatorParams params) throws IOException;<a name="line.126"></a>
<span class="sourceLineNo">127</span><a name="line.127"></a>
<span class="sourceLineNo">128</span> /**<a name="line.128"></a>
<span class="sourceLineNo">129</span> * Retrieve a RegionLocator implementation to inspect region information on a table. The returned<a name="line.129"></a>
<span class="sourceLineNo">130</span> * RegionLocator is not thread-safe, so a new instance should be created for each using thread.<a name="line.130"></a>
<span class="sourceLineNo">131</span> * This is a lightweight operation. Pooling or caching of the returned RegionLocator is neither<a name="line.131"></a>
<span class="sourceLineNo">132</span> * required nor desired. &lt;br&gt;<a name="line.132"></a>
<span class="sourceLineNo">133</span> * The caller is responsible for calling {@link RegionLocator#close()} on the returned<a name="line.133"></a>
<span class="sourceLineNo">134</span> * RegionLocator instance. RegionLocator needs to be unmanaged<a name="line.134"></a>
<span class="sourceLineNo">135</span> * @param tableName Name of the table who's region is to be examined<a name="line.135"></a>
<span class="sourceLineNo">136</span> * @return A RegionLocator instance<a name="line.136"></a>
<span class="sourceLineNo">137</span> */<a name="line.137"></a>
<span class="sourceLineNo">138</span> RegionLocator getRegionLocator(TableName tableName) throws IOException;<a name="line.138"></a>
<span class="sourceLineNo">139</span><a name="line.139"></a>
<span class="sourceLineNo">140</span> /**<a name="line.140"></a>
<span class="sourceLineNo">141</span> * Clear all the entries in the region location cache, for all the tables.<a name="line.141"></a>
<span class="sourceLineNo">142</span> * &lt;p/&gt;<a name="line.142"></a>
<span class="sourceLineNo">143</span> * If you only want to clear the cache for a specific table, use<a name="line.143"></a>
<span class="sourceLineNo">144</span> * {@link RegionLocator#clearRegionLocationCache()}.<a name="line.144"></a>
<span class="sourceLineNo">145</span> * &lt;p/&gt;<a name="line.145"></a>
<span class="sourceLineNo">146</span> * This may cause performance issue so use it with caution.<a name="line.146"></a>
<span class="sourceLineNo">147</span> */<a name="line.147"></a>
<span class="sourceLineNo">148</span> void clearRegionLocationCache();<a name="line.148"></a>
<span class="sourceLineNo">149</span><a name="line.149"></a>
<span class="sourceLineNo">150</span> /**<a name="line.150"></a>
<span class="sourceLineNo">151</span> * Retrieve an Admin implementation to administer an HBase cluster. The returned Admin is not<a name="line.151"></a>
<span class="sourceLineNo">152</span> * guaranteed to be thread-safe. A new instance should be created for each using thread. This is a<a name="line.152"></a>
<span class="sourceLineNo">153</span> * lightweight operation. Pooling or caching of the returned Admin is not recommended. &lt;br&gt;<a name="line.153"></a>
<span class="sourceLineNo">154</span> * The caller is responsible for calling {@link Admin#close()} on the returned Admin instance.<a name="line.154"></a>
<span class="sourceLineNo">155</span> * @return an Admin instance for cluster administration<a name="line.155"></a>
<span class="sourceLineNo">156</span> */<a name="line.156"></a>
<span class="sourceLineNo">157</span> Admin getAdmin() throws IOException;<a name="line.157"></a>
<span class="sourceLineNo">158</span><a name="line.158"></a>
<span class="sourceLineNo">159</span> @Override<a name="line.159"></a>
<span class="sourceLineNo">160</span> void close() throws IOException;<a name="line.160"></a>
<span class="sourceLineNo">161</span><a name="line.161"></a>
<span class="sourceLineNo">162</span> /**<a name="line.162"></a>
<span class="sourceLineNo">163</span> * Returns whether the connection is closed or not.<a name="line.163"></a>
<span class="sourceLineNo">164</span> * @return true if this connection is closed<a name="line.164"></a>
<span class="sourceLineNo">165</span> */<a name="line.165"></a>
<span class="sourceLineNo">166</span> boolean isClosed();<a name="line.166"></a>
<span class="sourceLineNo">167</span><a name="line.167"></a>
<span class="sourceLineNo">168</span> /**<a name="line.168"></a>
<span class="sourceLineNo">169</span> * Returns an {@link TableBuilder} for creating {@link Table}.<a name="line.169"></a>
<span class="sourceLineNo">170</span> * @param tableName the name of the table<a name="line.170"></a>
<span class="sourceLineNo">171</span> * @param pool the thread pool to use for requests like batch and scan<a name="line.171"></a>
<span class="sourceLineNo">172</span> */<a name="line.172"></a>
<span class="sourceLineNo">173</span> TableBuilder getTableBuilder(TableName tableName, ExecutorService pool);<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> * Convert this connection to an {@link AsyncConnection}.<a name="line.176"></a>
<span class="sourceLineNo">177</span> * &lt;p/&gt;<a name="line.177"></a>
<span class="sourceLineNo">178</span> * Usually we will return the same instance if you call this method multiple times so you can<a name="line.178"></a>
<span class="sourceLineNo">179</span> * consider this as a light-weighted operation.<a name="line.179"></a>
<span class="sourceLineNo">180</span> */<a name="line.180"></a>
<span class="sourceLineNo">181</span> AsyncConnection toAsyncConnection();<a name="line.181"></a>
<span class="sourceLineNo">182</span><a name="line.182"></a>
<span class="sourceLineNo">183</span> /** Returns the cluster ID unique to this HBase cluster. */<a name="line.183"></a>
<span class="sourceLineNo">184</span> String getClusterId();<a name="line.184"></a>
<span class="sourceLineNo">185</span><a name="line.185"></a>
<span class="sourceLineNo">186</span> /**<a name="line.186"></a>
<span class="sourceLineNo">187</span> * Retrieve an Hbck implementation to fix an HBase cluster. The returned Hbck is not guaranteed to<a name="line.187"></a>
<span class="sourceLineNo">188</span> * be thread-safe. A new instance should be created by each thread. This is a lightweight<a name="line.188"></a>
<span class="sourceLineNo">189</span> * operation. Pooling or caching of the returned Hbck instance is not recommended. &lt;br&gt;<a name="line.189"></a>
<span class="sourceLineNo">190</span> * The caller is responsible for calling {@link Hbck#close()} on the returned Hbck instance. &lt;br&gt;<a name="line.190"></a>
<span class="sourceLineNo">191</span> * This will be used mostly by hbck tool.<a name="line.191"></a>
<span class="sourceLineNo">192</span> * @return an Hbck instance for active master. Active master is fetched from the zookeeper.<a name="line.192"></a>
<span class="sourceLineNo">193</span> */<a name="line.193"></a>
<span class="sourceLineNo">194</span> @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.HBCK)<a name="line.194"></a>
<span class="sourceLineNo">195</span> default Hbck getHbck() throws IOException {<a name="line.195"></a>
<span class="sourceLineNo">196</span> return FutureUtils.get(toAsyncConnection().getHbck());<a name="line.196"></a>
<span class="sourceLineNo">197</span> }<a name="line.197"></a>
<span class="sourceLineNo">198</span><a name="line.198"></a>
<span class="sourceLineNo">199</span> /**<a name="line.199"></a>
<span class="sourceLineNo">200</span> * Retrieve an Hbck implementation to fix an HBase cluster. The returned Hbck is not guaranteed to<a name="line.200"></a>
<span class="sourceLineNo">201</span> * be thread-safe. A new instance should be created by each thread. This is a lightweight<a name="line.201"></a>
<span class="sourceLineNo">202</span> * operation. Pooling or caching of the returned Hbck instance is not recommended. &lt;br&gt;<a name="line.202"></a>
<span class="sourceLineNo">203</span> * The caller is responsible for calling {@link Hbck#close()} on the returned Hbck instance. &lt;br&gt;<a name="line.203"></a>
<span class="sourceLineNo">204</span> * This will be used mostly by hbck tool. This may only be used to by pass getting registered<a name="line.204"></a>
<span class="sourceLineNo">205</span> * master from ZK. In situations where ZK is not available or active master is not registered with<a name="line.205"></a>
<span class="sourceLineNo">206</span> * ZK and user can get master address by other means, master can be explicitly specified.<a name="line.206"></a>
<span class="sourceLineNo">207</span> * @param masterServer explicit {@link ServerName} for master server<a name="line.207"></a>
<span class="sourceLineNo">208</span> * @return an Hbck instance for a specified master server<a name="line.208"></a>
<span class="sourceLineNo">209</span> */<a name="line.209"></a>
<span class="sourceLineNo">210</span> @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.HBCK)<a name="line.210"></a>
<span class="sourceLineNo">211</span> default Hbck getHbck(ServerName masterServer) throws IOException {<a name="line.211"></a>
<span class="sourceLineNo">212</span> return toAsyncConnection().getHbck(masterServer);<a name="line.212"></a>
<span class="sourceLineNo">213</span> }<a name="line.213"></a>
<span class="sourceLineNo">214</span>}<a name="line.214"></a>
</pre>
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