001 /* $Id: AbstractRulesImpl.java 729095 2008-12-23 20:32:22Z rahul $ 002 * 003 * Licensed to the Apache Software Foundation (ASF) under one or more 004 * contributor license agreements. See the NOTICE file distributed with 005 * this work for additional information regarding copyright ownership. 006 * The ASF licenses this file to You under the Apache License, Version 2.0 007 * (the "License"); you may not use this file except in compliance with 008 * the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018 019 020 package org.apache.commons.digester; 021 022 023 import java.util.List; 024 025 026 /** 027 * <p><code>AbstractRuleImpl</code> provides basic services for <code>Rules</code> implementations. 028 * Extending this class should make it easier to create a <code>Rules</code> implementation.</p> 029 * 030 * <p><code>AbstractRuleImpl</code> manages the <code>Digester</code> 031 * and <code>namespaceUri</code> properties. 032 * If the subclass overrides {@link #registerRule} (rather than {@link #add}), 033 * then the <code>Digester</code> and <code>namespaceURI</code> of the <code>Rule</code> 034 * will be set correctly before it is passed to <code>registerRule</code>. 035 * The subclass can then perform whatever it needs to do to register the rule.</p> 036 * 037 * @since 1.5 038 */ 039 040 abstract public class AbstractRulesImpl implements Rules { 041 042 // ------------------------------------------------------------- Fields 043 044 /** Digester using this <code>Rules</code> implementation */ 045 private Digester digester; 046 /** Namespace uri to assoicate with subsequent <code>Rule</code>'s */ 047 private String namespaceURI; 048 049 // ------------------------------------------------------------- Properties 050 051 /** 052 * Return the Digester instance with which this Rules instance is 053 * associated. 054 */ 055 public Digester getDigester() { 056 return digester; 057 } 058 059 /** 060 * Set the Digester instance with which this Rules instance is associated. 061 * 062 * @param digester The newly associated Digester instance 063 */ 064 public void setDigester(Digester digester) { 065 this.digester = digester; 066 } 067 068 /** 069 * Return the namespace URI that will be applied to all subsequently 070 * added <code>Rule</code> objects. 071 */ 072 public String getNamespaceURI() { 073 return namespaceURI; 074 } 075 076 /** 077 * Set the namespace URI that will be applied to all subsequently 078 * added <code>Rule</code> objects. 079 * 080 * @param namespaceURI Namespace URI that must match on all 081 * subsequently added rules, or <code>null</code> for matching 082 * regardless of the current namespace URI 083 */ 084 public void setNamespaceURI(String namespaceURI) { 085 this.namespaceURI = namespaceURI; 086 } 087 088 // --------------------------------------------------------- Public Methods 089 090 /** 091 * Registers a new Rule instance matching the specified pattern. 092 * This implementation sets the <code>Digester</code> and the 093 * <code>namespaceURI</code> on the <code>Rule</code> before calling {@link #registerRule}. 094 * 095 * @param pattern Nesting pattern to be matched for this Rule 096 * @param rule Rule instance to be registered 097 */ 098 public void add(String pattern, Rule rule) { 099 // set up rule 100 if (this.digester != null) { 101 rule.setDigester(this.digester); 102 } 103 104 if (this.namespaceURI != null) { 105 rule.setNamespaceURI(this.namespaceURI); 106 } 107 108 registerRule(pattern, rule); 109 110 } 111 112 /** 113 * Register rule at given pattern. 114 * The the Digester and namespaceURI properties of the given <code>Rule</code> 115 * can be assumed to have been set properly before this method is called. 116 * 117 * @param pattern Nesting pattern to be matched for this Rule 118 * @param rule Rule instance to be registered 119 */ 120 abstract protected void registerRule(String pattern, Rule rule); 121 122 /** 123 * Clear all existing Rule instance registrations. 124 */ 125 abstract public void clear(); 126 127 128 /** 129 * Return a List of all registered Rule instances that match the specified 130 * nesting pattern, or a zero-length List if there are no matches. If more 131 * than one Rule instance matches, they <strong>must</strong> be returned 132 * in the order originally registered through the <code>add()</code> 133 * method. 134 * 135 * @param pattern Nesting pattern to be matched 136 * 137 * @deprecated Call match(namespaceURI,pattern) instead. 138 */ 139 public List<Rule> match(String pattern) { 140 return match(namespaceURI, pattern); 141 } 142 143 144 /** 145 * Return a List of all registered Rule instances that match the specified 146 * nesting pattern, or a zero-length List if there are no matches. If more 147 * than one Rule instance matches, they <strong>must</strong> be returned 148 * in the order originally registered through the <code>add()</code> 149 * method. 150 * 151 * @param namespaceURI Namespace URI for which to select matching rules, 152 * or <code>null</code> to match regardless of namespace URI 153 * @param pattern Nesting pattern to be matched 154 */ 155 abstract public List<Rule> match(String namespaceURI, String pattern); 156 157 158 /** 159 * Return a List of all registered Rule instances, or a zero-length List 160 * if there are no registered Rule instances. If more than one Rule 161 * instance has been registered, they <strong>must</strong> be returned 162 * in the order originally registered through the <code>add()</code> 163 * method. 164 */ 165 abstract public List<Rule> rules(); 166 167 }