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 (C) Intalio, Inc. All Rights Reserved.
32 *
33 * $Id$
34 */
35
36 package org.exolab.castor.mapping;
37
38 /**
39 * A field handler knows how to perform various operations on the field that require access to the
40 * field value.
41 *
42 * @author <a href="arkin@intalio.com">Assaf Arkin</a>
43 * @version $Revision$ $Date: 2003-03-03 00:05:44 -0700 (Mon, 03 Mar 2003) $
44 * @see FieldDescriptor
45 */
46 public interface FieldHandler<T> {
47
48 /**
49 * Returns the value of the field from the object.
50 *
51 * @param object The object
52 * @return The value of the field
53 * @throws IllegalStateException The Java object has changed and is no longer supported by this
54 * handler, or the handler is not compatible with the Java object
55 */
56 public T getValue(Object object) throws IllegalStateException;
57
58 /**
59 * Sets the value of the field on the object.
60 *
61 * @param object The object.
62 * @param value The new value.
63 * @throws IllegalStateException The Java object has changed and is no longer supported by this
64 * handler, or the handler is not compatible with the Java object.
65 * @throws IllegalArgumentException The value passed is not of a supported type.
66 */
67 public void setValue(Object object, T value)
68 throws IllegalStateException, IllegalArgumentException;
69
70 /**
71 * Sets the value of the field to a default value.
72 * <p>
73 * Reference fields are set to null, primitive fields are set to their default value, collection
74 * fields are emptied of all elements.
75 *
76 * @param object The object.
77 * @throws IllegalStateException The Java object has changed and is no longer supported by this
78 * handler, or the handler is not compatible with the Java object.
79 */
80 public void resetValue(Object object) throws IllegalStateException, IllegalArgumentException;
81
82 /**
83 * @deprecated No longer supported
84 */
85 public void checkValidity(Object object) throws ValidityException, IllegalStateException;
86
87 /**
88 * Creates a new instance of the object described by this field.
89 *
90 * @param parent The object for which the field is created
91 * @return A new instance of the field's value
92 * @throws IllegalStateException This field is a simple type and cannot be instantiated
93 */
94 public T newInstance(Object parent) throws IllegalStateException;
95
96 }