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1   /**
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  
19  package org.apache.hadoop.hbase.regionserver.wal;
20  
21  import java.lang.reflect.Constructor;
22  import java.lang.reflect.InvocationTargetException;
23  
24  /**
25   * Context that holds the various dictionaries for compression in HLog.
26   */
27  class CompressionContext {
28    final Dictionary regionDict;
29    final Dictionary tableDict;
30    final Dictionary familyDict;
31    final Dictionary qualifierDict;
32    final Dictionary rowDict;
33  
34    public CompressionContext(Class<? extends Dictionary> dictType)
35    throws SecurityException, NoSuchMethodException, InstantiationException,
36        IllegalAccessException, InvocationTargetException {
37      Constructor<? extends Dictionary> dictConstructor =
38          dictType.getConstructor();
39      regionDict = dictConstructor.newInstance();
40      tableDict = dictConstructor.newInstance();
41      familyDict = dictConstructor.newInstance();
42      qualifierDict = dictConstructor.newInstance();
43      rowDict = dictConstructor.newInstance();
44    }
45  
46    void clear() {
47      regionDict.clear();
48      tableDict.clear();
49      familyDict.clear();
50      qualifierDict.clear();
51      rowDict.clear();
52    }
53  }