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 package org.apache.hadoop.hbase.regionserver.wal; 21 22 import java.io.IOException; 23 import org.apache.hadoop.fs.Path; 24 import org.apache.hadoop.hbase.HRegionInfo; 25 import org.apache.hadoop.hbase.HTableDescriptor; 26 27 /** 28 * Get notification of {@link HLog}/WAL log events. The invocations are inline 29 * so make sure your implementation is fast else you'll slow hbase. 30 */ 31 public interface WALActionsListener { 32 33 /** 34 * The WAL is going to be rolled. The oldPath can be null if this is 35 * the first log file from the regionserver. 36 * @param oldPath the path to the old hlog 37 * @param newPath the path to the new hlog 38 */ 39 public void preLogRoll(Path oldPath, Path newPath) throws IOException; 40 41 /** 42 * The WAL has been rolled. The oldPath can be null if this is 43 * the first log file from the regionserver. 44 * @param oldPath the path to the old hlog 45 * @param newPath the path to the new hlog 46 */ 47 public void postLogRoll(Path oldPath, Path newPath) throws IOException; 48 49 /** 50 * The WAL is going to be archived. 51 * @param oldPath the path to the old hlog 52 * @param newPath the path to the new hlog 53 */ 54 public void preLogArchive(Path oldPath, Path newPath) throws IOException; 55 56 /** 57 * The WAL has been archived. 58 * @param oldPath the path to the old hlog 59 * @param newPath the path to the new hlog 60 */ 61 public void postLogArchive(Path oldPath, Path newPath) throws IOException; 62 63 /** 64 * A request was made that the WAL be rolled. 65 */ 66 public void logRollRequested(); 67 68 /** 69 * The WAL is about to close. 70 */ 71 public void logCloseRequested(); 72 73 /** 74 * Called before each write. 75 * @param info 76 * @param logKey 77 * @param logEdit 78 */ 79 public void visitLogEntryBeforeWrite(HRegionInfo info, HLogKey logKey, 80 WALEdit logEdit); 81 82 /** 83 * 84 * @param htd 85 * @param logKey 86 * @param logEdit 87 */ 88 public void visitLogEntryBeforeWrite(HTableDescriptor htd, HLogKey logKey, 89 WALEdit logEdit); 90 91 }