1 /**
2 * Redistribution and use of this software and associated documentation
3 * ("Software"), with or without modification, are permitted provided
4 * that the following conditions are met:
5 *
6 * 1. Redistributions of source code must retain copyright
7 * statements and notices. Redistributions must also contain a
8 * copy of this document.
9 *
10 * 2. Redistributions in binary form must reproduce the
11 * above copyright notice, this list of conditions and the
12 * following disclaimer in the documentation and/or other
13 * materials provided with the distribution.
14 *
15 * 3. The name "Exolab" must not be used to endorse or promote
16 * products derived from this Software without prior written
17 * permission of Intalio, Inc. For written permission,
18 * please contact info@exolab.org.
19 *
20 * 4. Products derived from this Software may not be called "Exolab"
21 * nor may "Exolab" appear in their names without prior written
22 * permission of Intalio, Inc. Exolab is a registered
23 * trademark of Intalio, Inc.
24 *
25 * 5. Due credit should be given to the Exolab Project
26 * (http://www.exolab.org/).
27 *
28 * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
32 * INTALIO, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39 * OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Copyright 1999-2003 (C) Intalio, Inc. All Rights Reserved.
42 *
43 * $Id$
44 */
45
46 package org.exolab.castor.xml;
47
48 import org.exolab.castor.mapping.AbstractFieldHandler;
49
50 /**
51 * This FieldHandler is used in the generated descriptors.
52 * <p>
53 * A field handler knows how to perform various operations on the field that
54 * require access to the field value.
55 * </p>
56 *
57 * @author <a href="arkin@intalio.com">Assaf Arkin</a>
58 * @author <a href="kvisco@intalio.com">Keith Visco</a>
59 * @version $Revision$ $Date: 2006-04-14 04:14:43 -0600 (Fri, 14 Apr
60 * 2006) $
61 * @see org.exolab.castor.mapping.FieldDescriptor
62 */
63 public class XMLFieldHandler<T> extends AbstractFieldHandler<T> {
64
65 /**
66 * Creates a new default XMLFieldHandler instance.
67 */
68 public XMLFieldHandler() {
69 super();
70 }
71
72 /**
73 * Returns true if the given object is an XMLFieldHandler that is equivalent
74 * to this one. An equivalent XMLFieldHandler is an XMLFieldHandler that is
75 * an instances of the same class. This method can be overwritten to provide
76 * more advanced equivalence tests.
77 *
78 * @return true if the given object is an XMLFieldHandler that is equivalent
79 * to this one.
80 **/
81 public boolean equals(Object obj) {
82 if (obj == null) {
83 return false;
84 }
85 if (!(obj instanceof XMLFieldHandler)) {
86 return false;
87 }
88 return getClass().isInstance(obj);
89 }
90
91 /**
92 * Returns the value of the field from the object.
93 *
94 * @param object
95 * The object
96 * @return The value of the field
97 * @throws IllegalStateException
98 * The Java object has changed and is no longer supported by this
99 * handler, or the handler is not compatiable with the Java object
100 */
101 public T getValue(Object object) throws IllegalStateException {
102 // -- Do nothing, this method is overloaded by the
103 // -- source code generator
104 return null;
105 }
106
107 /**
108 * Creates a new instance of the object described by this field.
109 *
110 * @param parent
111 * The object for which the field is created
112 * @return A new instance of the field's value
113 * @throws IllegalStateException
114 * This field is a simple type and cannot be instantiated
115 */
116 public T newInstance(Object parent) throws IllegalStateException {
117 // -- Do nothing, this method is overloaded by the
118 // -- source code generator
119 return null;
120 }
121
122 /**
123 * Creates a new instance of the object described by this field.
124 *
125 * @param parent
126 * The object for which the field is created
127 * @param args
128 * the set of constructor arguments
129 * @return A new instance of the field's value
130 * @throws IllegalStateException
131 * This field is a simple type and cannot be instantiated
132 */
133 public Object newInstance(final Object parent, final Object[] args) throws IllegalStateException {
134 // -- backward compatability...ignore args
135 return newInstance(parent);
136 }
137
138 /**
139 * Sets the value of the field on the object.
140 *
141 * @param object
142 * The object.
143 * @param value
144 * The new value.
145 * @throws IllegalStateException
146 * The Java object has changed and is no longer supported by this
147 * handler, or the handler is not compatiable with the Java
148 * object.
149 * @throws IllegalArgumentException
150 * The value passed is not of a supported type.
151 */
152 public void setValue(final Object object, final T value) throws IllegalStateException,
153 IllegalArgumentException {
154 // -- Do nothing, this method is overloaded by the
155 // -- source code generator
156 }
157
158 public void resetValue(final Object object) throws IllegalStateException, IllegalArgumentException {
159 // -- Do nothing, this method is overloaded by the
160 // -- source code generator
161 }
162 }