001    /*
002     * $Id: Proxy.java 4098 2006-10-10 16:09:48Z blackdrag $
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 that the
008     * following conditions are met: 1. Redistributions of source code must retain
009     * copyright statements and notices. Redistributions must also contain a copy
010     * of this document. 2. Redistributions in binary form must reproduce the above
011     * copyright notice, this list of conditions and the following disclaimer in
012     * the documentation and/or other materials provided with the distribution. 3.
013     * The name "groovy" must not be used to endorse or promote products derived
014     * from this Software without prior written permission of The Codehaus. For
015     * written permission, please contact info@codehaus.org. 4. Products derived
016     * from this Software may not be called "groovy" nor may "groovy" appear in
017     * their names without prior written permission of The Codehaus. "groovy" is a
018     * registered trademark of The Codehaus. 5. Due credit should be given to The
019     * Codehaus - http://groovy.codehaus.org/
020     * 
021     * THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS ``AS IS'' AND ANY
022     * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
023     * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
024     * DISCLAIMED. IN NO EVENT SHALL THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR
025     * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
026     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
027     * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
028     * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
029     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
030     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
031     * DAMAGE.
032     *  
033     */
034    package groovy.util;
035    
036    import java.util.Iterator;
037    
038    import groovy.lang.GroovyObjectSupport;
039    import groovy.lang.MissingMethodException;
040    import org.codehaus.groovy.runtime.InvokerHelper;
041    
042    /**
043     * Dynamic groovy proxy for another object.  All method
044     * invocations get forwarded to actual object, unless the proxy overrides it.
045     * See groovy/util/ProxyTest.groovy for usage details.
046     *
047     * @author Troy Heninger
048     * @author Dierk Koenig
049     */
050    public class Proxy extends GroovyObjectSupport {
051    
052        private Object adaptee = null;
053    
054        /**
055         * This method is for convenience.
056         * It allows to get around the need for defining dump ctors is subclasses.
057         * See unit tests for details.
058         */
059        public Proxy wrap(Object adaptee){
060            setAdaptee(adaptee);
061            return this;
062        }
063    
064        public Object getAdaptee() {
065            return adaptee;
066        }
067    
068        public void setAdaptee(Object adaptee) {
069            this.adaptee = adaptee;
070        }
071    
072        public Object invokeMethod(String name, Object args) {
073            try {
074                return super.invokeMethod(name, args);
075            }
076            catch (MissingMethodException e) {
077                return InvokerHelper.getMetaClass(adaptee).invokeMethod(adaptee, name, args);
078            }
079        }
080        
081        public Iterator iterator() {
082            return InvokerHelper.asIterator(adaptee);
083        }
084    
085    }