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    1   /*
    2    * $Id: Proxy.java,v 1.5 2005/10/03 18:07:36 tug Exp $
    3    *
    4    * Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
    5    *
    6    * Redistribution and use of this software and associated documentation
    7    * ("Software"), with or without modification, are permitted provided that the
    8    * following conditions are met: 1. Redistributions of source code must retain
    9    * copyright statements and notices. Redistributions must also contain a copy
    10   * of this document. 2. Redistributions in binary form must reproduce the above
    11   * copyright notice, this list of conditions and the following disclaimer in
    12   * the documentation and/or other materials provided with the distribution. 3.
    13   * The name "groovy" must not be used to endorse or promote products derived
    14   * from this Software without prior written permission of The Codehaus. For
    15   * written permission, please contact info@codehaus.org. 4. Products derived
    16   * from this Software may not be called "groovy" nor may "groovy" appear in
    17   * their names without prior written permission of The Codehaus. "groovy" is a
    18   * registered trademark of The Codehaus. 5. Due credit should be given to The
    19   * Codehaus - http://groovy.codehaus.org/
    20   *
    21   * THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS ``AS IS'' AND ANY
    22   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    23   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    24   * DISCLAIMED. IN NO EVENT SHALL THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR
    25   * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    26   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    27   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    28   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    29   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    30   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
    31   * DAMAGE.
    32   *
    33   */
    34  package groovy.util;
    35
    36  import groovy.lang.GroovyObjectSupport;
    37  import groovy.lang.MissingMethodException;
    38  import org.codehaus.groovy.runtime.InvokerHelper;
    39
    40  /***
    41   * Dynamic groovy proxy for another object.  All method
    42   * invocations get forwarded to actual object, unless the proxy overrides it.
    43   * See groovy/util/ProxyTest.groovy for usage details.
    44   *
    45   * @author Troy Heninger
    46   * @author Dierk Koenig
    47   */
    48  public class Proxy extends GroovyObjectSupport {
    49
    50      private Object adaptee = null;
    51
    52      /***
    53       * This method is for convenience.
    54       * It allows to get around the need for defining dump ctors is subclasses.
    55       * See unit tests for details.
    56       */
    57      public Proxy wrap(Object adaptee){
    58          setAdaptee(adaptee);
    59          return this;
    60      }
    61
    62      public Object getAdaptee() {
    63          return adaptee;
    64      }
    65
    66      public void setAdaptee(Object adaptee) {
    67          this.adaptee = adaptee;
    68      }
    69
    70      public Object invokeMethod(String name, Object args) {
    71          try {
    72              return super.invokeMethod(name, args);
    73          }
    74          catch (MissingMethodException e) {
    75              return InvokerHelper.getMetaClass(adaptee).invokeMethod(adaptee, name, args);
    76          }
    77      }
    78
    79  }