/*
 * 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.configuration.event;


An event class that is used for reporting errors that occurred while
processing configuration properties.

 Some configuration implementations (e.g. DatabaseConfiguration or JNDIConfiguration use an underlying storage that can throw an exception on each property access. In earlier versions of this library such exceptions were logged and then silently ignored. This makes it impossible for a client to find out that something went wrong. 

To give clients better control over the handling of errors that occur during
access of a configuration object a new event listener mechanism specific for
exceptions is introduced: Clients can register itself at a configuration
object as an error listener and are then notified about all
internal errors related to the source configuration object.

 By inheriting from ConfigurationEvent this event class supports all properties that describe an operation on a configuration instance. In addition a Throwable object is available representing the occurred error. The event's type determines the operation that caused the error. Note that depending on the event type and the occurred exception not all of the other properties (e.g. name of the affected property or its value) may be available. 
Author:
Commons
Configuration team
See Also:
ConfigurationEvent
Version:
$Id: ConfigurationErrorEvent.java 1207610 2011-11-28 21:06:22Z oheger $
Since:
1.4/**
 * <p>
 * An event class that is used for reporting errors that occurred while
 * processing configuration properties.
 * </p>
 * <p>
 * Some configuration implementations (e.g.
 * {@link org.apache.commons.configuration.DatabaseConfiguration}
 * or {@link org.apache.commons.configuration.JNDIConfiguration}
 * use an underlying storage that can throw an exception on each property
 * access. In earlier versions of this library such exceptions were logged and
 * then silently ignored. This makes it impossible for a client to find out that
 * something went wrong.
 * </p>
 * <p>
 * To give clients better control over the handling of errors that occur during
 * access of a configuration object a new event listener mechanism specific for
 * exceptions is introduced: Clients can register itself at a configuration
 * object as an <em>error listener</em> and are then notified about all
 * internal errors related to the source configuration object.
 * </p>
 * <p>
 * By inheriting from {@code ConfigurationEvent} this event class
 * supports all properties that describe an operation on a configuration
 * instance. In addition a {@code Throwable} object is available
 * representing the occurred error. The event's type determines the operation
 * that caused the error. Note that depending on the event type and the occurred
 * exception not all of the other properties (e.g. name of the affected property
 * or its value) may be available.
 * </p>
 *
 * @author <a
 * href="http://commons.apache.org/configuration/team-list.html">Commons
 * Configuration team</a>
 * @version $Id: ConfigurationErrorEvent.java 1207610 2011-11-28 21:06:22Z oheger $
 * @since 1.4
 * @see ConfigurationEvent
 */
public class ConfigurationErrorEvent extends ConfigurationEvent
{
    
The serial version UID.
/**
     * The serial version UID.
     */
    private static final long serialVersionUID = -7433184493062648409L;

    
Stores the exception that caused this event. /** Stores the exception that caused this event. */
    private Throwable cause;

    
Creates a new instance of ConfigurationErrorEvent and initializes it. 
Params:
source – the event source
type – the event's type
propertyName – the name of the affected property
propertyValue – the value of the affected property
cause – the exception object that caused this event/**
     * Creates a new instance of {@code ConfigurationErrorEvent} and
     * initializes it.
     *
     * @param source the event source
     * @param type the event's type
     * @param propertyName the name of the affected property
     * @param propertyValue the value of the affected property
     * @param cause the exception object that caused this event
     */
    public ConfigurationErrorEvent(Object source, int type,
            String propertyName, Object propertyValue, Throwable cause)
    {
        super(source, type, propertyName, propertyValue, true);
        this.cause = cause;
    }

    
Returns the cause of this error event. This is the Throwable object that caused this event to be fired. 
Returns:
the cause of this error event/**
     * Returns the cause of this error event. This is the {@code Throwable}
     * object that caused this event to be fired.
     *
     * @return the cause of this error event
     */
    public Throwable getCause()
    {
        return cause;
    }
}