/*
 * 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.configuration2.builder;

import org.apache.commons.configuration2.event.Event;
import org.apache.commons.configuration2.event.EventType;

 A base event class for events generated by a ConfigurationBuilder. 
 Configuration builders can trigger a number of different events. All these events are derived from this class. This event base class does not define any additional properties. However, it defines that the event source must be a ConfigurationBuilder. 
Since:
2.0/**
 * <p>
 * A base event class for events generated by a {@link ConfigurationBuilder}.
 * </p>
 * <p>
 * Configuration builders can trigger a number of different events. All these
 * events are derived from this class. This event base class does not define any
 * additional properties. However, it defines that the event source must be a
 * {@code ConfigurationBuilder}.
 * </p>
 *
 * @since 2.0
 */
public class ConfigurationBuilderEvent extends Event
{
    
The common super type for all events related to configuration builders. /** The common super type for all events related to configuration builders. */
    public static final EventType<ConfigurationBuilderEvent> ANY =
            new EventType<>(Event.ANY, "BUILDER");

    
The specific event type for builder reset events. Events of this type are generated each time the builder's resetResult() method is called. /**
     * The specific event type for builder reset events. Events of this type are
     * generated each time the builder's {@code resetResult()} method is called.
     */
    public static final EventType<ConfigurationBuilderEvent> RESET =
            new EventType<>(ANY, "RESET");

    
The specific event type for configuration request events. Events of this type are generated each time the builder's getConfiguration() method is called (before the managed configuration is actually accessed and the lock is acquired). This gives listeners the opportunity to perform some checks which may invalidate the configuration, e.g. trigger a reload check. Note: A listener must not call the builder's getConfiguration() method - this will cause an infinite loop! 
See Also:
ConfigurationBuilder.getConfiguration()/**
     * The specific event type for configuration request events. Events of this
     * type are generated each time the builder's {@code getConfiguration()}
     * method is called (before the managed configuration is actually accessed
     * and the lock is acquired). This gives listeners the opportunity to
     * perform some checks which may invalidate the configuration, e.g. trigger
     * a reload check. <strong>Note:</strong> A listener must not call the
     * builder's {@code getConfiguration()} method - this will cause an
     * infinite loop!
     *
     * @see ConfigurationBuilder#getConfiguration()
     */
    public static final EventType<ConfigurationBuilderEvent> CONFIGURATION_REQUEST =
            new EventType<>(ANY,
                    "CONFIGURATION_REQUEST");

    
Creates a new instance of ConfigurationBuilderEvent and sets basic properties. 
Params:
source – the ConfigurationBuilder object which triggered this event (must not be null)
evType – the type of this event (must not be null)
Throws:
IllegalArgumentException – if a required parameter is null/**
     * Creates a new instance of {@code ConfigurationBuilderEvent} and sets
     * basic properties.
     *
     * @param source the {@code ConfigurationBuilder} object which triggered
     *        this event (must not be <b>null</b>)
     * @param evType the type of this event (must not be <b>null</b>)
     * @throws IllegalArgumentException if a required parameter is null
     */
    public ConfigurationBuilderEvent(final ConfigurationBuilder<?> source,
            final EventType<? extends ConfigurationBuilderEvent> evType)
    {
        super(source, evType);
    }

    
Returns the source of this event as a ConfigurationBuilder. 
Returns:
the ConfigurationBuilder which generated this event/**
     * Returns the source of this event as a {@code ConfigurationBuilder}.
     *
     * @return the {@code ConfigurationBuilder} which generated this event
     */
    @Override
    public ConfigurationBuilder<?> getSource()
    {
        return (ConfigurationBuilder<?>) super.getSource();
    }
}