View Javadoc

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  
20  package org.apache.hadoop.hbase.zookeeper;
21  
22  import java.util.Properties;
23  import java.util.Map.Entry;
24  
25  import org.apache.hadoop.hbase.classification.InterfaceAudience;
26  import org.apache.hadoop.conf.Configuration;
27  import org.apache.hadoop.hbase.HBaseConfiguration;
28  import org.apache.hadoop.hbase.HBaseInterfaceAudience;
29  
30  /**
31   * Tool for reading ZooKeeper servers from HBase XML configuration and producing
32   * a line-by-line list for use by bash scripts.
33   */
34  @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.TOOLS)
35  public class ZKServerTool {
36    /**
37     * Run the tool.
38     * @param args Command line arguments.
39     */
40    public static void main(String args[]) {
41      Configuration conf = HBaseConfiguration.create();
42      // Note that we do not simply grab the property
43      // HConstants.ZOOKEEPER_QUORUM from the HBaseConfiguration because the
44      // user may be using a zoo.cfg file.
45      Properties zkProps = ZKConfig.makeZKProps(conf);
46      for (Entry<Object, Object> entry : zkProps.entrySet()) {
47        String key = entry.getKey().toString().trim();
48        String value = entry.getValue().toString().trim();
49        if (key.startsWith("server.")) {
50          String[] parts = value.split(":");
51          String host = parts[0];
52          System.out.println("ZK host:" + host);
53        }
54      }
55    }
56  }