org.apache.commons.digester.plugins.PluginAssertionFailure Maven / Gradle / Ivy
/* $Id: PluginAssertionFailure.java 729089 2008-12-23 20:22:26Z rahul $
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.digester.plugins;
/**
* Thrown when a bug is detected in the plugins code.
*
* This class is intended to be used in assertion statements, similar to
* the way that java 1.4's native assertion mechanism is used. However there
* is a difference: when a java 1.4 assertion fails, an AssertionError
* is thrown, which is a subclass of Error; here, the PluginAssertionFailure
* class extends RuntimeException rather than Error.
*
* This difference in design is because throwing Error objects is not
* good in a container-based architecture.
*
* Example:
*
* if (impossibleCondition) {
* throw new PluginAssertionFailure(
* "internal error: impossible condition is true");
* }
*
*
* Note that PluginAssertionFailure should not be thrown when user
* input is bad, or when code external to the Digester module passes invalid
* parameters to a plugins method. It should be used only in checks for
* problems which indicate internal bugs within the plugins module.
*
* @since 1.6
*/
public class PluginAssertionFailure extends RuntimeException {
private static final long serialVersionUID = 1L;
private Throwable cause = null;
/**
* @param cause underlying exception that caused this to be thrown
*/
public PluginAssertionFailure(Throwable cause) {
this(cause.getMessage());
this.cause = cause;
}
/**
* @param msg describes the reason this exception is being thrown.
*/
public PluginAssertionFailure(String msg) {
super(msg);
}
/**
* @param msg describes the reason this exception is being thrown.
* @param cause underlying exception that caused this to be thrown
*/
public PluginAssertionFailure(String msg, Throwable cause) {
this(msg);
this.cause = cause;
}
/**
* Return the cause of this exception (if any) as specified in the
* exception constructor.
*
* @since 1.8
*/
public Throwable getCause() {
return cause;
}
}