001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.commons.io.input; 018 019 /** 020 * Listener for events from a {@link Tailer}. 021 * 022 * @version $Id: TailerListener.java 1178224 2011-10-02 19:09:57Z ggregory $ 023 * @since Commons IO 2.0 024 */ 025 public interface TailerListener { 026 027 /** 028 * The tailer will call this method during construction, 029 * giving the listener a method of stopping the tailer. 030 * @param tailer the tailer. 031 */ 032 void init(Tailer tailer); 033 034 /** 035 * This method is called if the tailed file is not found. 036 * <p> 037 * <b>Note:</b> this is called from the tailer thread. 038 */ 039 void fileNotFound(); 040 041 /** 042 * Called if a file rotation is detected. 043 * 044 * This method is called before the file is reopened, and fileNotFound may 045 * be called if the new file has not yet been created. 046 * <p> 047 * <b>Note:</b> this is called from the tailer thread. 048 */ 049 void fileRotated(); 050 051 /** 052 * Handles a line from a Tailer. 053 * <p> 054 * <b>Note:</b> this is called from the tailer thread. 055 * @param line the line. 056 */ 057 void handle(String line); 058 059 /** 060 * Handles an Exception . 061 * <p> 062 * <b>Note:</b> this is called from the tailer thread. 063 * @param ex the exception. 064 */ 065 void handle(Exception ex); 066 067 }