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.fs.Path;
25 import org.apache.hadoop.hbase.HRegionInfo;
26 import org.apache.hadoop.hbase.HTableDescriptor;
27
28 /**
29 * Get notification of {@link FSHLog}/WAL log events. The invocations are inline
30 * so make sure your implementation is fast else you'll slow hbase.
31 */
32 @InterfaceAudience.Private
33 public interface WALActionsListener {
34
35 /**
36 * The WAL is going to be rolled. The oldPath can be null if this is
37 * the first log file from the regionserver.
38 * @param oldPath the path to the old hlog
39 * @param newPath the path to the new hlog
40 */
41 void preLogRoll(Path oldPath, Path newPath) throws IOException;
42
43 /**
44 * The WAL has been rolled. The oldPath can be null if this is
45 * the first log file from the regionserver.
46 * @param oldPath the path to the old hlog
47 * @param newPath the path to the new hlog
48 */
49 void postLogRoll(Path oldPath, Path newPath) throws IOException;
50
51 /**
52 * The WAL is going to be archived.
53 * @param oldPath the path to the old hlog
54 * @param newPath the path to the new hlog
55 */
56 void preLogArchive(Path oldPath, Path newPath) throws IOException;
57
58 /**
59 * The WAL has been archived.
60 * @param oldPath the path to the old hlog
61 * @param newPath the path to the new hlog
62 */
63 void postLogArchive(Path oldPath, Path newPath) throws IOException;
64
65 /**
66 * A request was made that the WAL be rolled.
67 */
68 void logRollRequested();
69
70 /**
71 * The WAL is about to close.
72 */
73 void logCloseRequested();
74
75 /**
76 * Called before each write.
77 * @param info
78 * @param logKey
79 * @param logEdit
80 */
81 void visitLogEntryBeforeWrite(
82 HRegionInfo info, HLogKey logKey, WALEdit logEdit
83 );
84
85 /**
86 *
87 * @param htd
88 * @param logKey
89 * @param logEdit
90 */
91 void visitLogEntryBeforeWrite(
92 HTableDescriptor htd, HLogKey logKey, WALEdit logEdit
93 );
94
95 }