001/* 002 * GWTEventService 003 * Copyright (c) 2011 and beyond, strawbill UG (haftungsbeschr?nkt) 004 * 005 * This is free software; you can redistribute it and/or modify it 006 * under the terms of the GNU Lesser General Public License as 007 * published by the Free Software Foundation; either version 3 of 008 * the License, or (at your option) any later version. 009 * Other licensing for GWTEventService may also be possible on request. 010 * Please view the license.txt of the project for more information. 011 * 012 * This software is distributed in the hope that it will be useful, 013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 015 * Lesser General Public License for more details. 016 * 017 * You should have received a copy of the GNU Lesser General Public 018 * License along with this software; if not, write to the Free 019 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 020 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 021 */ 022package de.novanic.eventservice.client.event.filter; 023 024/** 025 * The EventFilterFactory can be used to connect various {@link de.novanic.eventservice.client.event.filter.EventFilter} 026 * instances by creating a {@link de.novanic.eventservice.client.event.filter.CompositeEventFilter}. 027 * A other solution to build filter sequences is available with {@link CascadingEventFilter} (cascading filter sequences). 028 * 029 * @author sstrohschein 030 * <br>Date: 04.03.2009 031 * <br>Time: 19:21:21 032 */ 033public class EventFilterFactory 034{ 035 /** 036 * The EventFilterFactory should be created via the getInstance method. 037 * @see EventFilterFactory#getInstance() 038 */ 039 private EventFilterFactory() {} 040 041 /** 042 * Factory-Holder class to ensure thread-safe lazy-loading with IODH. 043 */ 044 private static class EventFilterFactoryHolder { 045 private static final EventFilterFactory INSTANCE = new EventFilterFactory(); 046 } 047 048 /** 049 * This method should be used to create an instance of EventFilterFactory. 050 * EventFilterFactory is a singleton, so this method returns always the same instance of 051 * EventFilterFactory. 052 * @return EventFilterFactory (singleton) 053 */ 054 public static EventFilterFactory getInstance() { 055 return EventFilterFactoryHolder.INSTANCE; 056 } 057 058 /** 059 * That method can connect various {@link de.novanic.eventservice.client.event.filter.EventFilter} instances by 060 * building a {@link de.novanic.eventservice.client.event.filter.CompositeEventFilter}. 061 * @param anEventFilters {@link de.novanic.eventservice.client.event.filter.EventFilter} instances to build a 062 * {@link de.novanic.eventservice.client.event.filter.CompositeEventFilter}. 063 * @return {@link de.novanic.eventservice.client.event.filter.CompositeEventFilter} which contains the connectable 064 * {@link de.novanic.eventservice.client.event.filter.EventFilter} instances. 065 */ 066 public CompositeEventFilter connect(EventFilter... anEventFilters) { 067 return new DefaultCompositeEventFilter(anEventFilters); 068 } 069}