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 1999-2002 (C) Intalio, Inc. All Rights Reserved.
32 *
33 * $Id$
34 */
35
36 package org.exolab.castor.mapping;
37
38 import java.util.Properties;
39
40 /**
41 * An extended version of the FieldHandler interface which is used for adding additional
42 * functionality while preserving backward compatability.
43 *
44 * @author <a href="kvisco@intalio.com">Keith Visco</a>
45 * @version $Revision$ $Date: 2005-08-03 15:11:51 -0600 (Wed, 03 Aug 2005) $
46 * @see FieldDescriptor
47 * @see FieldHandler
48 */
49 public abstract class AbstractFieldHandler<T> extends ExtendedFieldHandler<T>
50 implements ConfigurableFieldHandler<T> {
51
52 /**
53 * The FieldDescriptor for the field that this handler is responsible for.
54 */
55 private FieldDescriptor _descriptor = null;
56
57 /**
58 * Configuration that can be used by subclasses when needed.
59 */
60 protected Properties _properties;
61
62 /**
63 * {@inheritDoc}
64 */
65 protected final FieldDescriptor getFieldDescriptor() {
66 return _descriptor;
67 }
68
69 /**
70 * {@inheritDoc}
71 */
72 public void setFieldDescriptor(FieldDescriptor fieldDesc) {
73 _descriptor = fieldDesc;
74 }
75
76 /**
77 * Returns true if the "handled" field has a value within the given object.
78 * <p>
79 * By default this just checks for null. Normally this method is needed for checking if a value
80 * has been set via a call to the setValue method, or if the primitive value has been initialised
81 * by the JVM.
82 * </p>
83 * <p>
84 * This method should be overloaded for improved value checking.
85 * </p>
86 *
87 * @return true if the given object has a value for the handled field
88 */
89 public boolean hasValue(final Object object) {
90 return (getValue(object) != null);
91 }
92
93 /**
94 * Empty implementation of the {@link ConfigurableFieldHandler} interface, for convenience
95 * purpose. Subclasses that want to use any configuration should override this method.
96 *
97 * @param config The configuration as specified in the mapping file.
98 */
99 public void setConfiguration(final Properties config) throws ValidityException {}
100 }