1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.configuration2.builder; 18 19 import org.apache.commons.configuration2.event.Event; 20 import org.apache.commons.configuration2.event.EventType; 21 22 /** 23 * <p> 24 * A base event class for events generated by a {@link ConfigurationBuilder}. 25 * </p> 26 * <p> 27 * Configuration builders can trigger a number of different events. All these events are derived from this class. This 28 * event base class does not define any additional properties. However, it defines that the event source must be a 29 * {@code ConfigurationBuilder}. 30 * </p> 31 * 32 * @since 2.0 33 */ 34 public class ConfigurationBuilderEvent extends Event { 35 36 private static final long serialVersionUID = -7488811456039315104L; 37 38 /** The common super type for all events related to configuration builders. */ 39 public static final EventType<ConfigurationBuilderEvent> ANY = new EventType<>(Event.ANY, "BUILDER"); 40 41 /** 42 * The specific event type for builder reset events. Events of this type are generated each time the builder's 43 * {@code resetResult()} method is called. 44 */ 45 public static final EventType<ConfigurationBuilderEvent> RESET = new EventType<>(ANY, "RESET"); 46 47 /** 48 * The specific event type for configuration request events. Events of this type are generated each time the builder's 49 * {@code getConfiguration()} method is called (before the managed configuration is actually accessed and the lock is 50 * acquired). This gives listeners the opportunity to perform some checks which may invalidate the configuration, e.g. 51 * trigger a reload check. <strong>Note:</strong> A listener must not call the builder's {@code getConfiguration()} 52 * method - this will cause an infinite loop! 53 * 54 * @see ConfigurationBuilder#getConfiguration() 55 */ 56 public static final EventType<ConfigurationBuilderEvent> CONFIGURATION_REQUEST = new EventType<>(ANY, "CONFIGURATION_REQUEST"); 57 58 /** 59 * Creates a new instance of {@code ConfigurationBuilderEvent} and sets basic properties. 60 * 61 * @param source the {@code ConfigurationBuilder} object which triggered this event (must not be <b>null</b>) 62 * @param evType the type of this event (must not be <b>null</b>) 63 * @throws IllegalArgumentException if a required parameter is null 64 */ 65 public ConfigurationBuilderEvent(final ConfigurationBuilder<?> source, final EventType<? extends ConfigurationBuilderEvent> evType) { 66 super(source, evType); 67 } 68 69 /** 70 * Gets the source of this event as a {@code ConfigurationBuilder}. 71 * 72 * @return the {@code ConfigurationBuilder} which generated this event 73 */ 74 @Override 75 public ConfigurationBuilder<?> getSource() { 76 return (ConfigurationBuilder<?>) super.getSource(); 77 } 78 }