001 package org.apache.commons.digester3; 002 003 /* 004 * Licensed to the Apache Software Foundation (ASF) under one 005 * or more contributor license agreements. See the NOTICE file 006 * distributed with this work for additional information 007 * regarding copyright ownership. The ASF licenses this file 008 * to you under the Apache License, Version 2.0 (the 009 * "License"); you may not use this file except in compliance 010 * with the License. You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, 015 * software distributed under the License is distributed on an 016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 017 * KIND, either express or implied. See the License for the 018 * specific language governing permissions and limitations 019 * under the License. 020 */ 021 022 import static java.lang.String.format; 023 024 import org.xml.sax.Attributes; 025 026 /** 027 * Rule implementation that creates a new object and pushes it onto the object stack. When the element is complete, the 028 * object will be popped 029 */ 030 public class ObjectCreateRule 031 extends Rule 032 { 033 034 // ----------------------------------------------------------- Constructors 035 036 /** 037 * Construct an object create rule with the specified class name. 038 * 039 * @param className Java class name of the object to be created 040 */ 041 public ObjectCreateRule( String className ) 042 { 043 this( className, (String) null ); 044 } 045 046 /** 047 * Construct an object create rule with the specified class. 048 * 049 * @param clazz Java class name of the object to be created 050 */ 051 public ObjectCreateRule( Class<?> clazz ) 052 { 053 this( clazz.getName(), (String) null ); 054 this.clazz = clazz; 055 } 056 057 /** 058 * Construct an object create rule with the specified class name and an optional attribute name containing an 059 * override. 060 * 061 * @param className Java class name of the object to be created 062 * @param attributeName Attribute name which, if present, contains an override of the class name to create 063 */ 064 public ObjectCreateRule( String className, String attributeName ) 065 { 066 this.className = className; 067 this.attributeName = attributeName; 068 } 069 070 /** 071 * Construct an object create rule with the specified class and an optional attribute name containing an override. 072 * 073 * @param attributeName Attribute name which, if present, contains an 074 * @param clazz Java class name of the object to be created override of the class name to create 075 */ 076 public ObjectCreateRule( String attributeName, Class<?> clazz ) 077 { 078 this( clazz.getName(), attributeName ); 079 this.clazz = clazz; 080 } 081 082 // ----------------------------------------------------- Instance Variables 083 084 /** 085 * The attribute containing an override class name if it is present. 086 */ 087 protected String attributeName = null; 088 089 /** 090 * The Java class of the object to be created. 091 */ 092 protected Class<?> clazz = null; 093 094 /** 095 * The Java class name of the object to be created. 096 */ 097 protected String className = null; 098 099 // --------------------------------------------------------- Public Methods 100 101 /** 102 * {@inheritDoc} 103 */ 104 @Override 105 public void begin( String namespace, String name, Attributes attributes ) 106 throws Exception 107 { 108 Class<?> clazz = this.clazz; 109 110 if ( clazz == null ) 111 { 112 // Identify the name of the class to instantiate 113 String realClassName = className; 114 if ( attributeName != null ) 115 { 116 String value = attributes.getValue( attributeName ); 117 if ( value != null ) 118 { 119 realClassName = value; 120 } 121 } 122 if ( getDigester().getLogger().isDebugEnabled() ) 123 { 124 getDigester().getLogger().debug( format( "[ObjectCreateRule]{%s} New '%s'", 125 getDigester().getMatch(), 126 realClassName ) ); 127 } 128 129 // Instantiate the new object and push it on the context stack 130 clazz = getDigester().getClassLoader().loadClass( realClassName ); 131 } 132 Object instance = clazz.newInstance(); 133 getDigester().push( instance ); 134 } 135 136 /** 137 * {@inheritDoc} 138 */ 139 @Override 140 public void end( String namespace, String name ) 141 throws Exception 142 { 143 Object top = getDigester().pop(); 144 if ( getDigester().getLogger().isDebugEnabled() ) 145 { 146 getDigester().getLogger().debug( format( "[ObjectCreateRule]{%s} Pop '%s'", 147 getDigester().getMatch(), 148 top.getClass().getName() ) ); 149 } 150 } 151 152 /** 153 * {@inheritDoc} 154 */ 155 @Override 156 public String toString() 157 { 158 return format( "ObjectCreateRule[className=%s, attributeName=%s]", className, attributeName ); 159 } 160 161 }