1 /*
2 $Id: ValueHolder.java,v 1.1 2003/10/24 12:47:15 jstrachan 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
8 that the following conditions are met:
9
10 1. Redistributions of source code must retain copyright
11 statements and notices. Redistributions must also contain a
12 copy of this document.
13
14 2. Redistributions in binary form must reproduce the
15 above copyright notice, this list of conditions and the
16 following disclaimer in the documentation and/or other
17 materials provided with the distribution.
18
19 3. The name "groovy" must not be used to endorse or promote
20 products derived from this Software without prior written
21 permission of The Codehaus. For written permission,
22 please contact info@codehaus.org.
23
24 4. Products derived from this Software may not be called "groovy"
25 nor may "groovy" appear in their names without prior written
26 permission of The Codehaus. "groovy" is a registered
27 trademark of The Codehaus.
28
29 5. Due credit should be given to The Codehaus -
30 http://groovy.codehaus.org/
31
32 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
33 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
34 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
35 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
36 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43 OF THE POSSIBILITY OF SUCH DAMAGE.
44
45 */
46 package groovy.model;
47
48 import java.beans.PropertyChangeListener;
49 import java.beans.PropertyChangeSupport;
50
51 /***
52 * A simple ValueModle implementation which is a holder of an object value.
53 * Used to share local variables with closures
54 *
55 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
56 * @version $Revision: 1.1 $
57 */
58 public class ValueHolder implements ValueModel {
59 private Object value;
60 private Class type;
61 private PropertyChangeSupport propertyChangeSupport;
62 private boolean editable = true;
63
64 public ValueHolder() {
65 this(Object.class);
66 }
67
68 public ValueHolder(Class type) {
69 this.type = type;
70 }
71
72 public ValueHolder(Object value) {
73 this.value = value;
74 this.type = (value != null) ? value.getClass() : Object.class;
75 }
76
77 /***
78 * Add a PropertyChangeListener to the listener list.
79 * @param l The listener to add.
80 */
81 public void addPropertyChangeListener(PropertyChangeListener listener) {
82 if ( propertyChangeSupport == null ) {
83 propertyChangeSupport = new PropertyChangeSupport(this);
84 }
85 propertyChangeSupport.addPropertyChangeListener(listener);
86 }
87
88 /***
89 * Removes a PropertyChangeListener from the listener list.
90 * @param l The listener to remove.
91 */
92 public void removePropertyChangeListener(PropertyChangeListener listener) {
93 if ( propertyChangeSupport != null ) {
94 propertyChangeSupport.removePropertyChangeListener(listener);
95 }
96 }
97
98
99 public Object getValue() {
100 return value;
101 }
102
103 public void setValue(Object value) {
104 Object oldValue = this.value;
105 this.value = value;
106 if ( propertyChangeSupport != null ) {
107 propertyChangeSupport.firePropertyChange("value", oldValue, value);
108 }
109 }
110
111 public Class getType() {
112 return type;
113 }
114
115 public boolean isEditable() {
116 return editable;
117 }
118
119 public void setEditable(boolean editable) {
120 this.editable = editable;
121 }
122
123 }