001// Copyright 2006, 2007, 2008, 2011 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry5.services; 016 017/** 018 * An object which manages a list of {@link org.apache.tapestry5.services.InvalidationListener}s. There are multiple 019 * event hub services implementing this interface, each with a specific marker annotation; each can register listeners 020 * and fire events; these are based on the type of resource that has been invalidated. Tapestry has built-in support 021 * for: 022 * <dl> 023 * <dt>message catalog resources 024 * <dd>{@link org.apache.tapestry5.services.ComponentMessages} marker annotation 025 * <dt>component templates 026 * <dd>{@link org.apache.tapestry5.services.ComponentTemplates} marker annotation 027 * <dt>component classes 028 * <dd>{@link org.apache.tapestry5.services.ComponentClasses} marker annotation 029 * </dl> 030 * <p> 031 * Starting in Tapestry 5.3, these services are disabled in production (it does nothing). 032 * 033 * @since 5.1.0.0 034 */ 035public interface InvalidationEventHub 036{ 037 /** 038 * Adds a listener, who needs to know when an underlying resource of a given category has changed (so that the 039 * receiver may discard any cached data that may have been invalidated). Does nothing in production mode. 040 */ 041 void addInvalidationListener(InvalidationListener listener); 042}