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.regionserver.wal;
20
21 import java.io.IOException;
22
23 import org.apache.hadoop.classification.InterfaceAudience;
24 import org.apache.hadoop.conf.Configuration;
25 import org.apache.hadoop.fs.Path;
26 import org.apache.hadoop.hbase.HConstants;
27 import org.apache.hadoop.hbase.util.FSUtils;
28
29 /**
30 * Context used by our wal dictionary compressor. Null if we're not to do our
31 * custom dictionary compression.
32 */
33 @InterfaceAudience.Private
34 public abstract class WriterBase implements HLog.Writer {
35
36 protected CompressionContext compressionContext;
37
38 public boolean initializeCompressionContext(Configuration conf, Path path) throws IOException {
39 boolean doCompress = conf.getBoolean(HConstants.ENABLE_WAL_COMPRESSION, false);
40 if (doCompress) {
41 try {
42 this.compressionContext = new CompressionContext(LRUDictionary.class,
43 FSUtils.isRecoveredEdits(path));
44 } catch (Exception e) {
45 throw new IOException("Failed to initiate CompressionContext", e);
46 }
47 }
48 return doCompress;
49 }
50 }