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.configuration.event;
018    
019    /**
020     * <p>
021     * An event listener interface to be implemented by observers that are
022     * interested in internal errors caused by processing of configuration
023     * properties.
024     * </p>
025     * <p>
026     * Some configuration classes use an underlying storage where each access of a
027     * property can cause an exception. In earlier versions of this library such
028     * exceptions were typically ignored. By implementing this interface and
029     * registering at a configuration object as an error listener it is now possible
030     * for clients to receive notifications about those internal problems.
031     * </p>
032     *
033     * @author <a
034     * href="http://commons.apache.org/configuration/team-list.html">Commons
035     * Configuration team</a>
036     * @version $Id: ConfigurationErrorListener.java 561230 2007-07-31 04:17:09Z rahul $
037     * @since 1.4
038     * @see ConfigurationErrorEvent
039     */
040    public interface ConfigurationErrorListener
041    {
042        /**
043         * Notifies this listener that in an observed configuration an error
044         * occurred. All information available about this error, including the
045         * causing <code>Throwable</code> object, can be obtained from the passed
046         * in event object.
047         *
048         * @param event the event object with information about the error
049         */
050        void configurationError(ConfigurationErrorEvent event);
051    }