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1   /*
2    * $Id: MetaFieldProperty.java,v 1.4 2005/08/25 22:08:35 phk 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:
9    *  1. Redistributions of source code must retain copyright statements and
10   * notices. Redistributions must also contain a copy of this document.
11   *  2. Redistributions in binary form must reproduce the above copyright
12   * notice, this list of conditions and the following disclaimer in the
13   * documentation and/or other materials provided with the distribution.
14   *  3. The name "groovy" must not be used to endorse or promote products
15   * derived from this Software without prior written permission of The Codehaus.
16   * For written permission, please contact info@codehaus.org.
17   *  4. Products derived from this Software may not be called "groovy" nor may
18   * "groovy" appear in their names without prior written permission of The
19   * Codehaus. "groovy" is a registered trademark of The Codehaus.
20   *  5. Due credit should be given to The Codehaus - http://groovy.codehaus.org/
21   *
22   * THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS ``AS IS'' AND ANY
23   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25   * DISCLAIMED. IN NO EVENT SHALL THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR
26   * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
28   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
29   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
32   * DAMAGE.
33   *
34   */
35   
36  package groovy.lang;
37  
38  
39  import org.codehaus.groovy.runtime.InvokerHelper;
40  import java.lang.reflect.Field;
41  import java.security.AccessController;
42  import java.security.PrivilegedExceptionAction;
43  
44  /***
45   * Represents a property on a bean which may have a getter and/or a setter
46   * 
47   * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
48   * @version $Revision: 1.4 $
49   */
50  public class MetaFieldProperty extends MetaProperty {
51  
52      private Field field;
53  
54      public MetaFieldProperty(Field field) {
55          super(field.getName(), field.getType());
56          this.field = field;
57      }
58  
59      /***
60       * @return the property of the given object
61       * @throws Exception if the property could not be evaluated
62       */
63      public Object getProperty(Object object) throws Exception {
64          final Field field1 = field;
65          final Object object1 = object;
66          Object value = (Object) AccessController.doPrivileged(new PrivilegedExceptionAction() {
67               public Object run() throws IllegalAccessException {   
68                   field1.setAccessible(true);
69                   return field1.get(object1);
70               }
71          });
72          return value;
73      }
74  
75      /***
76       * Sets the property on the given object to the new value
77       * 
78       * @param object on which to set the property
79       * @param newValue the new value of the property
80       * @throws Exception if the property could not be set
81       */
82      public void setProperty(Object object, Object newValue) {
83          final Field field1 = field;
84          final Object object1 = object;
85          final Object newValue1 = newValue;
86          try {
87              AccessController.doPrivileged(new PrivilegedExceptionAction() {
88                  public Object run() throws IllegalAccessException, TypeMismatchException, GroovyRuntimeException {   
89                      try {
90                          field1.set(object1, newValue1);
91                          return newValue1;
92                      }
93                      catch (IllegalArgumentException e) {
94                          try {
95                              Object newValue2 = InvokerHelper.asType(newValue1, field1.getType());
96                              field1.set(object1, newValue2);
97                              return newValue2;
98                          }
99                          catch (Exception ex) {
100                             throw new TypeMismatchException( "'" + toName(object1.getClass()) + "." + field1.getName()
101                                                                  + "' can not refer to the value '"
102                                                                  + newValue1 + "' (type " + toName(newValue1.getClass())
103                                                                  + "), because it is of the type " + toName(field1.getType()) );
104                         }
105                     }
106                     catch (Exception ex) {
107                         throw new GroovyRuntimeException("Cannot set the property '" + name + "'.", ex);
108                     }
109                 }
110             });
111         }
112         catch (TypeMismatchException ex) {
113             throw ex;
114         }
115         catch (Exception ex) {
116             throw new GroovyRuntimeException("Cannot set the property '" + name + "'.", ex);
117         }
118     }
119 
120     private String toName(Class c) {
121         String s = c.toString();
122         if (s.startsWith("class ") && s.length() > 6)
123             return s.substring(6);
124         else
125             return s;
126     }
127 }