001 /* 002 $Id: Expando.java,v 1.6 2005/07/16 20:00:26 phk 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.ParameterArray; 049 import groovy.lang.Closure; 050 import groovy.lang.GroovyObjectSupport; 051 import groovy.lang.GroovyRuntimeException; 052 import groovy.lang.MetaExpandoProperty; 053 054 import java.util.HashMap; 055 import java.util.Map; 056 import java.util.Map.Entry; 057 import java.util.List; 058 import java.util.ArrayList; 059 import java.util.Iterator; 060 061 062 /** 063 * Represents a dynamically expandable bean. 064 * 065 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a> 066 * @author Hein Meling 067 * @author Pilho Kim 068 * @version $Revision: 1.6 $ 069 */ 070 public class Expando extends GroovyObjectSupport { 071 072 private Map expandoProperties; 073 074 public Expando() { 075 } 076 077 public Expando(Map expandoProperties) { 078 this.expandoProperties = expandoProperties; 079 } 080 081 /** 082 * @return the dynamically expanded properties 083 */ 084 public Map getExpandoProperties() { 085 if (expandoProperties == null) { 086 expandoProperties = createMap(); 087 } 088 return expandoProperties; 089 } 090 091 public List getProperties() { 092 // run through all our current properties and create MetaProperty objects 093 List ret = new ArrayList(); 094 Iterator itr = getExpandoProperties().entrySet().iterator(); 095 while(itr.hasNext()) { 096 Entry entry = (Entry) itr.next(); 097 ret.add(new MetaExpandoProperty(entry)); 098 } 099 100 return ret; 101 } 102 103 public Object getProperty(String property) { 104 try { 105 return super.getProperty(property); 106 } 107 catch (GroovyRuntimeException e) { 108 return getExpandoProperties().get(property); 109 } 110 } 111 112 public void setProperty(String property, Object newValue) { 113 try { 114 super.setProperty(property, newValue); 115 } 116 catch (GroovyRuntimeException e) { 117 getExpandoProperties().put(property, newValue); 118 } 119 } 120 121 public Object invokeMethod(String name, Object args) { 122 try { 123 return super.invokeMethod(name, args); 124 } 125 catch (GroovyRuntimeException e) { 126 // br should get a "native" property match first. getProperty includes such fall-back logic 127 Object value = this.getProperty(name); 128 if (value instanceof Closure) { 129 Closure closure = (Closure) value; 130 closure.setDelegate(this); 131 return closure.call(new ParameterArray(args)); 132 } 133 else { 134 throw e; 135 } 136 } 137 138 } 139 140 /** 141 * This allows toString to be overridden by a closure <i>field</i> method attached 142 * to the expando object. 143 * 144 * @see java.lang.Object#toString() 145 */ 146 public String toString() { 147 Object method = getExpandoProperties().get("toString"); 148 if (method != null && method instanceof Closure) { 149 // invoke overridden toString closure method 150 Closure closure = (Closure) method; 151 closure.setDelegate(this); 152 return closure.call().toString(); 153 } else { 154 return expandoProperties.toString(); 155 } 156 } 157 158 /** 159 * This allows equals to be overridden by a closure <i>field</i> method attached 160 * to the expando object. 161 * 162 * @see java.lang.Object#equals(java.lang.Object) 163 */ 164 public boolean equals(Object obj) { 165 Object method = getExpandoProperties().get("equals"); 166 if (method != null && method instanceof Closure) { 167 // invoke overridden equals closure method 168 Closure closure = (Closure) method; 169 closure.setDelegate(this); 170 Boolean ret = (Boolean) closure.call(obj); 171 return ret.booleanValue(); 172 } else { 173 return super.equals(obj); 174 } 175 } 176 177 /** 178 * This allows hashCode to be overridden by a closure <i>field</i> method attached 179 * to the expando object. 180 * 181 * @see java.lang.Object#hashCode() 182 */ 183 public int hashCode() { 184 Object method = getExpandoProperties().get("hashCode"); 185 if (method != null && method instanceof Closure) { 186 // invoke overridden hashCode closure method 187 Closure closure = (Closure) method; 188 closure.setDelegate(this); 189 Integer ret = (Integer) closure.call(); 190 return ret.intValue(); 191 } else { 192 return super.hashCode(); 193 } 194 } 195 196 /** 197 * Factory method to create a new Map used to store the expando properties map 198 * @return a newly created Map implementation 199 */ 200 protected Map createMap() { 201 return new HashMap(); 202 } 203 204 }