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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.master.normalizer;
20  
21  import org.apache.hadoop.conf.Configuration;
22  import org.apache.hadoop.hbase.HConstants;
23  import org.apache.hadoop.hbase.classification.InterfaceAudience;
24  import org.apache.hadoop.util.ReflectionUtils;
25  
26  /**
27   * Factory to create instance of {@link RegionNormalizer} as configured.
28   */
29  @InterfaceAudience.Private
30  public final class RegionNormalizerFactory {
31  
32    private RegionNormalizerFactory() {
33    }
34  
35    /**
36     * Create a region normalizer from the given conf.
37     * @param conf configuration
38     * @return {@link RegionNormalizer} implementation
39     */
40    public static RegionNormalizer getRegionNormalizer(Configuration conf) {
41  
42      // Create instance of Region Normalizer
43      Class<? extends RegionNormalizer> balancerKlass =
44        conf.getClass(HConstants.HBASE_MASTER_NORMALIZER_CLASS, SimpleRegionNormalizer.class,
45          RegionNormalizer.class);
46      return ReflectionUtils.newInstance(balancerKlass, conf);
47    }
48  }