1 /**
2 * Redistribution and use of this software and associated documentation ("Software"), with or
3 * without modification, are permitted provided that the following conditions are met:
4 *
5 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions
6 * must also contain a copy of this document.
7 *
8 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
9 * conditions and the following disclaimer in the documentation and/or other materials provided with
10 * the distribution.
11 *
12 * 3. The name "Exolab" must not be used to endorse or promote products derived from this Software
13 * without prior written permission of Intalio, Inc. For written permission, please contact
14 * info@exolab.org.
15 *
16 * 4. Products derived from this Software may not be called "Exolab" nor may "Exolab" appear in
17 * their names without prior written permission of Intalio, Inc. Exolab is a registered trademark of
18 * Intalio, Inc.
19 *
20 * 5. Due credit should be given to the Exolab Project (http://www.exolab.org/).
21 *
22 * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
24 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTALIO, INC. OR ITS
25 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
28 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
29 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 * Copyright 1999-2003 (C) Intalio, Inc. All Rights Reserved.
32 *
33 * $Id$
34 */
35
36 package org.exolab.castor.xml;
37
38 import org.exolab.castor.mapping.AbstractFieldHandler;
39
40 /**
41 * This FieldHandler is used in the generated descriptors.
42 * <p>
43 * A field handler knows how to perform various operations on the field that require access to the
44 * field value.
45 * </p>
46 *
47 * @author <a href="arkin@intalio.com">Assaf Arkin</a>
48 * @author <a href="kvisco@intalio.com">Keith Visco</a>
49 * @version $Revision$ $Date: 2006-04-14 04:14:43 -0600 (Fri, 14 Apr 2006) $
50 * @see org.exolab.castor.mapping.FieldDescriptor
51 */
52 public class XMLFieldHandler<T> extends AbstractFieldHandler<T> {
53
54 /**
55 * Creates a new default XMLFieldHandler instance.
56 */
57 public XMLFieldHandler() {
58 super();
59 }
60
61 /**
62 * Returns true if the given object is an XMLFieldHandler that is equivalent to this one. An
63 * equivalent XMLFieldHandler is an XMLFieldHandler that is an instances of the same class. This
64 * method can be overwritten to provide more advanced equivalence tests.
65 *
66 * @return true if the given object is an XMLFieldHandler that is equivalent to this one.
67 **/
68 public boolean equals(Object obj) {
69 if (obj == null) {
70 return false;
71 }
72 if (!(obj instanceof XMLFieldHandler)) {
73 return false;
74 }
75 return getClass().isInstance(obj);
76 }
77
78 /**
79 * Returns the value of the field from the object.
80 *
81 * @param object The object
82 * @return The value of the field
83 * @throws IllegalStateException The Java object has changed and is no longer supported by this
84 * handler, or the handler is not compatiable with the Java object
85 */
86 public T getValue(Object object) throws IllegalStateException {
87 // -- Do nothing, this method is overloaded by the
88 // -- source code generator
89 return null;
90 }
91
92 /**
93 * Creates a new instance of the object described by this field.
94 *
95 * @param parent The object for which the field is created
96 * @return A new instance of the field's value
97 * @throws IllegalStateException This field is a simple type and cannot be instantiated
98 */
99 public T newInstance(Object parent) throws IllegalStateException {
100 // -- Do nothing, this method is overloaded by the
101 // -- source code generator
102 return null;
103 }
104
105 /**
106 * Creates a new instance of the object described by this field.
107 *
108 * @param parent The object for which the field is created
109 * @param args the set of constructor arguments
110 * @return A new instance of the field's value
111 * @throws IllegalStateException This field is a simple type and cannot be instantiated
112 */
113 public Object newInstance(final Object parent, final Object[] args) throws IllegalStateException {
114 // -- backward compatability...ignore args
115 return newInstance(parent);
116 }
117
118 /**
119 * Sets the value of the field on the object.
120 *
121 * @param object The object.
122 * @param value The new value.
123 * @throws IllegalStateException The Java object has changed and is no longer supported by this
124 * handler, or the handler is not compatiable with the Java object.
125 * @throws IllegalArgumentException The value passed is not of a supported type.
126 */
127 public void setValue(final Object object, final T value)
128 throws IllegalStateException, IllegalArgumentException {
129 // -- Do nothing, this method is overloaded by the
130 // -- source code generator
131 }
132
133 public void resetValue(final Object object)
134 throws IllegalStateException, IllegalArgumentException {
135 // -- Do nothing, this method is overloaded by the
136 // -- source code generator
137 }
138 }