1 package org.apache.commons.digester3.plugins; 2 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, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 22 /** 23 * Thrown when a bug is detected in the plugins code. 24 * <p> 25 * This class is intended to be used in assertion statements, similar to the way that java 1.4's native assertion 26 * mechanism is used. However there is a difference: when a java 1.4 assertion fails, an AssertionError is thrown, which 27 * is a subclass of Error; here, the PluginAssertionFailure class extends RuntimeException rather than Error. 28 * <p> 29 * This difference in design is because throwing Error objects is not good in a container-based architecture. 30 * <p> 31 * Example: 32 * 33 * <pre> 34 * if ( impossibleCondition ) 35 * { 36 * throw new PluginAssertionFailure( "internal error: impossible condition is true" ); 37 * } 38 * </pre> 39 * <p> 40 * Note that PluginAssertionFailure should <i>not</i> be thrown when user input is bad, or when code external to the 41 * Digester module passes invalid parameters to a plugins method. It should be used only in checks for problems which 42 * indicate internal bugs within the plugins module. 43 * 44 * @since 1.6 45 */ 46 public class PluginAssertionFailure 47 extends RuntimeException 48 { 49 50 private static final long serialVersionUID = 1L; 51 52 /** 53 * Constructs a new exception with the specified cause. 54 * 55 * @param cause underlying exception that caused this to be thrown 56 */ 57 public PluginAssertionFailure( Throwable cause ) 58 { 59 super( cause ); 60 } 61 62 /** 63 * Constructs a new exception with the specified detail message. 64 * 65 * @param msg describes the reason this exception is being thrown. 66 */ 67 public PluginAssertionFailure( String msg ) 68 { 69 super( msg ); 70 } 71 72 /** 73 * Constructs a new exception with the specified detail message and cause. 74 * 75 * @param msg describes the reason this exception is being thrown. 76 * @param cause underlying exception that caused this to be thrown 77 */ 78 public PluginAssertionFailure( String msg, Throwable cause ) 79 { 80 super( msg, cause ); 81 } 82 83 }