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1   /**
2    * Copyright 2011 The Apache Software Foundation
3    *
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *     http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing, software
15   * distributed under the License is distributed on an "AS IS" BASIS,
16   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17   * See the License for the specific language governing permissions and
18   * limitations under the License.
19   */
20  
21  package org.apache.hadoop.hbase.master;
22  
23  import org.apache.hadoop.conf.Configuration;
24  import org.apache.hadoop.hbase.HConstants;
25  import org.apache.hadoop.util.ReflectionUtils;
26  
27  /**
28   * The class that creates a load balancer from a conf.
29   */
30  public class LoadBalancerFactory {
31  
32    /**
33     * Create a loadblanacer from the given conf.
34     * @param conf
35     * @return A {@link LoadBalancer}
36     */
37    public static LoadBalancer getLoadBalancer(Configuration conf) {
38  
39      // Create the balancer
40      Class<? extends LoadBalancer> balancerKlass = conf.getClass(
41          HConstants.HBASE_MASTER_LOADBALANCER_CLASS,
42          DefaultLoadBalancer.class, LoadBalancer.class);
43      return ReflectionUtils.newInstance(balancerKlass, conf);
44  
45    }
46  }