001 //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.3_testing/src/org/deegree/model/feature/XLinkedFeatureProperty.java $
002 /*----------------------------------------------------------------------------
003 This file is part of deegree, http://deegree.org/
004 Copyright (C) 2001-2009 by:
005 Department of Geography, University of Bonn
006 and
007 lat/lon GmbH
008
009 This library is free software; you can redistribute it and/or modify it under
010 the terms of the GNU Lesser General Public License as published by the Free
011 Software Foundation; either version 2.1 of the License, or (at your option)
012 any later version.
013 This library is distributed in the hope that it will be useful, but WITHOUT
014 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
015 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
016 details.
017 You should have received a copy of the GNU Lesser General Public License
018 along with this library; if not, write to the Free Software Foundation, Inc.,
019 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
020
021 Contact information:
022
023 lat/lon GmbH
024 Aennchenstr. 19, 53177 Bonn
025 Germany
026 http://lat-lon.de/
027
028 Department of Geography, University of Bonn
029 Prof. Dr. Klaus Greve
030 Postfach 1147, 53001 Bonn
031 Germany
032 http://www.geographie.uni-bonn.de/deegree/
033
034 e-mail: info@deegree.org
035 ----------------------------------------------------------------------------*/
036 package org.deegree.model.feature;
037
038 import org.deegree.datatypes.QualifiedName;
039
040 /**
041 * Feature property instance that does not specify it's content inline, but references a feature
042 * instance via an XLink.
043 *
044 * @author <a href="mailto:schneider@lat-lon.de">Markus Schneider </a>
045 * @author last edited by: $Author: mschneider $
046 *
047 * @version $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18. Jun 2009) $
048 */
049 public class XLinkedFeatureProperty implements FeatureProperty {
050
051 private QualifiedName name;
052
053 private String targetFeatureId;
054
055 private Feature targetFeature;
056
057 /**
058 * Creates a new instance of <code>XLinkedFeatureProperty</code> from the given parameters.
059 * <p>
060 * NOTE: After creating, this property has no value. The reference to the target feature has to
061 * be resolved first by calling #setValue(java.lang.Object).
062 *
063 * @see #setValue(java.lang.Object)
064 *
065 * @param name
066 * feature name
067 * @param targetFeatureId
068 * id of the feature that this property contains
069 */
070 public XLinkedFeatureProperty( QualifiedName name, String targetFeatureId ) {
071 this.name = name;
072 this.targetFeatureId = targetFeatureId;
073 }
074
075 /**
076 * Returns the name of the property.
077 *
078 * @return the name of the property.
079 */
080 public QualifiedName getName() {
081 return this.name;
082 }
083
084 /**
085 * Returns the value of the property.
086 *
087 * @return the value of the property.
088 */
089 public Object getValue() {
090 checkResolved();
091 return this.targetFeature;
092 }
093
094 /**
095 * Returns the value of the property.
096 *
097 * @return the value of the property.
098 */
099 public Object getValue( Object defaultValue ) {
100 checkResolved();
101 if ( this.targetFeature == null ) {
102 return defaultValue;
103 }
104 return this.targetFeature;
105 }
106
107 /**
108 * Sets the target feature instance that this feature property refers to.
109 *
110 * @param value
111 * feature instance that this feature property refers to
112 * @throws RuntimeException
113 * if the reference has already been resolved
114 */
115 public void setValue( Object value ) {
116 if ( this.targetFeature != null ) {
117 String msg = Messages.format( "ERROR_REFERENCE_ALREADY_RESOLVED", this.targetFeatureId );
118 throw new RuntimeException( msg );
119 }
120 this.targetFeature = (Feature) value;
121 }
122
123 /*
124 * (non-Javadoc)
125 *
126 * @see org.deegree.model.feature.FeatureProperty#getOwner()
127 */
128 public Feature getOwner() {
129 return null;
130 }
131
132 /**
133 * Returns the feature id of the target feature.
134 *
135 * @return the feature id of the target feature.
136 */
137 public String getTargetFeatureId() {
138 return this.targetFeatureId;
139 }
140
141 /**
142 * Ensures that the reference to the target feature has been resolved.
143 *
144 * @throws RuntimeException
145 * if the reference has not been resolved
146 */
147 private void checkResolved() {
148 if ( this.targetFeature == null ) {
149 String msg = Messages.format( "ERROR_XLINK_NOT_RESOLVED", this.targetFeatureId );
150 throw new RuntimeException( msg );
151 }
152 }
153 }