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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase;
20  
21  import org.apache.hadoop.conf.Configuration;
22  import org.apache.hadoop.hbase.classification.InterfaceAudience;
23  import org.apache.hadoop.hbase.classification.InterfaceStability;
24  import org.apache.hadoop.hbase.client.ClusterConnection;
25  import org.apache.hadoop.hbase.client.Connection;
26  import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
27  import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
28  
29  /**
30   * Defines the set of shared functions implemented by HBase servers (Masters
31   * and RegionServers).
32   */
33  @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.COPROC)
34  @InterfaceStability.Evolving
35  public interface Server extends Abortable, Stoppable {
36    /**
37     * Gets the configuration object for this server.
38     */
39    Configuration getConfiguration();
40  
41    /**
42     * Gets the ZooKeeper instance for this server.
43     */
44    ZooKeeperWatcher getZooKeeper();
45  
46    /**
47     * Returns a reference to the servers' connection.
48     *
49     * Important note: this method returns a reference to Connection which is managed
50     * by Server itself, so callers must NOT attempt to close connection obtained.
51     */
52    Connection getConnection();
53  
54    /**
55     * Returns a reference to the servers' cluster connection. Prefer {@link #getConnection()}.
56     *
57     * Important note: this method returns a reference to Connection which is managed
58     * by Server itself, so callers must NOT attempt to close connection obtained.
59     */
60    ClusterConnection getClusterConnection();
61  
62    /**
63     * Returns instance of {@link org.apache.hadoop.hbase.zookeeper.MetaTableLocator}
64     * running inside this server. This MetaServerLocator is started and stopped by server, clients
65     * shouldn't manage it's lifecycle.
66     * @return instance of {@link MetaTableLocator} associated with this server.
67     */
68    MetaTableLocator getMetaTableLocator();
69  
70    /**
71     * @return The unique server name for this server.
72     */
73    ServerName getServerName();
74  
75    /**
76     * Get CoordinatedStateManager instance for this server.
77     */
78    CoordinatedStateManager getCoordinatedStateManager();
79  
80    /**
81     * @return The {@link ChoreService} instance for this server
82     */
83    ChoreService getChoreService();
84  }