001 /* 002 $Id: Expando.java,v 1.10 2005/10/03 18:07:36 tug Exp $ 003 004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved. 005 006 Redistribution and use of this software and associated documentation 007 ("Software"), with or without modification, are permitted provided 008 that the following conditions are met: 009 010 1. Redistributions of source code must retain copyright 011 statements and notices. Redistributions must also contain a 012 copy of this document. 013 014 2. Redistributions in binary form must reproduce the 015 above copyright notice, this list of conditions and the 016 following disclaimer in the documentation and/or other 017 materials provided with the distribution. 018 019 3. The name "groovy" must not be used to endorse or promote 020 products derived from this Software without prior written 021 permission of The Codehaus. For written permission, 022 please contact info@codehaus.org. 023 024 4. Products derived from this Software may not be called "groovy" 025 nor may "groovy" appear in their names without prior written 026 permission of The Codehaus. "groovy" is a registered 027 trademark of The Codehaus. 028 029 5. Due credit should be given to The Codehaus - 030 http://groovy.codehaus.org/ 031 032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS 033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT 034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 043 OF THE POSSIBILITY OF SUCH DAMAGE. 044 045 */ 046 package groovy.util; 047 048 import groovy.lang.Closure; 049 import groovy.lang.GroovyObjectSupport; 050 import groovy.lang.GroovyRuntimeException; 051 import groovy.lang.MetaExpandoProperty; 052 053 import java.util.HashMap; 054 import java.util.Map; 055 import java.util.Map.Entry; 056 import java.util.List; 057 import java.util.ArrayList; 058 import java.util.Iterator; 059 060 061 /** 062 * Represents a dynamically expandable bean. 063 * 064 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a> 065 * @author Hein Meling 066 * @author Pilho Kim 067 * @version $Revision: 1.10 $ 068 */ 069 public class Expando extends GroovyObjectSupport { 070 071 private Map expandoProperties; 072 073 public Expando() { 074 } 075 076 public Expando(Map expandoProperties) { 077 this.expandoProperties = expandoProperties; 078 } 079 080 /** 081 * @return the dynamically expanded properties 082 */ 083 public Map getProperties() { 084 if (expandoProperties == null) { 085 expandoProperties = createMap(); 086 } 087 return expandoProperties; 088 } 089 090 public List getMetaPropertyValues() { 091 // run through all our current properties and create MetaProperty objects 092 List ret = new ArrayList(); 093 Iterator itr = getProperties().entrySet().iterator(); 094 while(itr.hasNext()) { 095 Entry entry = (Entry) itr.next(); 096 ret.add(new MetaExpandoProperty(entry)); 097 } 098 099 return ret; 100 } 101 102 public Object getProperty(String property) { 103 try { 104 return super.getProperty(property); 105 } 106 catch (GroovyRuntimeException e) { 107 return getProperties().get(property); 108 } 109 } 110 111 public void setProperty(String property, Object newValue) { 112 try { 113 super.setProperty(property, newValue); 114 } 115 catch (GroovyRuntimeException e) { 116 getProperties().put(property, newValue); 117 } 118 } 119 120 public Object invokeMethod(String name, Object args) { 121 try { 122 return super.invokeMethod(name, args); 123 } 124 catch (GroovyRuntimeException e) { 125 // br should get a "native" property match first. getProperty includes such fall-back logic 126 Object value = this.getProperty(name); 127 if (value instanceof Closure) { 128 Closure closure = (Closure) value; 129 closure.setDelegate(this); 130 return closure.call((Object[]) args); 131 } 132 else { 133 throw e; 134 } 135 } 136 137 } 138 139 /** 140 * This allows toString to be overridden by a closure <i>field</i> method attached 141 * to the expando object. 142 * 143 * @see java.lang.Object#toString() 144 */ 145 public String toString() { 146 Object method = getProperties().get("toString"); 147 if (method != null && method instanceof Closure) { 148 // invoke overridden toString closure method 149 Closure closure = (Closure) method; 150 closure.setDelegate(this); 151 return closure.call().toString(); 152 } else { 153 return expandoProperties.toString(); 154 } 155 } 156 157 /** 158 * This allows equals to be overridden by a closure <i>field</i> method attached 159 * to the expando object. 160 * 161 * @see java.lang.Object#equals(java.lang.Object) 162 */ 163 public boolean equals(Object obj) { 164 Object method = getProperties().get("equals"); 165 if (method != null && method instanceof Closure) { 166 // invoke overridden equals closure method 167 Closure closure = (Closure) method; 168 closure.setDelegate(this); 169 Boolean ret = (Boolean) closure.call(obj); 170 return ret.booleanValue(); 171 } else { 172 return super.equals(obj); 173 } 174 } 175 176 /** 177 * This allows hashCode to be overridden by a closure <i>field</i> method attached 178 * to the expando object. 179 * 180 * @see java.lang.Object#hashCode() 181 */ 182 public int hashCode() { 183 Object method = getProperties().get("hashCode"); 184 if (method != null && method instanceof Closure) { 185 // invoke overridden hashCode closure method 186 Closure closure = (Closure) method; 187 closure.setDelegate(this); 188 Integer ret = (Integer) closure.call(); 189 return ret.intValue(); 190 } else { 191 return super.hashCode(); 192 } 193 } 194 195 /** 196 * Factory method to create a new Map used to store the expando properties map 197 * @return a newly created Map implementation 198 */ 199 protected Map createMap() { 200 return new HashMap(); 201 } 202 203 }