1 /**
2 * Licensed under the Artistic License; you may not use this file
3 * except in compliance with the License.
4 * You may obtain a copy of the License at
5 *
6 * http://displaytag.sourceforge.net/license.html
7 *
8 * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
9 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
10 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
11 */
12 package org.displaytag.decorator;
13
14 import org.displaytag.exception.ObjectLookupException;
15 import org.displaytag.render.TableWriterTemplate;
16 import org.displaytag.util.LookupUtil;
17 import org.displaytag.util.TagConstants;
18
19
20 /**
21 * @author epesh
22 * @author Fabrizio Giustina
23 * @version $Revision: 1084 $ ($Author: fgiust $)
24 */
25 public abstract class TableDecorator extends Decorator
26 {
27
28 /**
29 * object representing the current row.
30 */
31 private Object currentRowObject;
32
33 /**
34 * index in displayed list.
35 */
36 private int viewIndex = -1;
37
38 /**
39 * index in original list.
40 */
41 private int listIndex = -1;
42
43 /**
44 * Return the index in the displayed list.
45 * @return int index in the displayed list
46 */
47 public final int getViewIndex()
48 {
49 return this.viewIndex;
50 }
51
52 /**
53 * Return the index in the full list (view index + offset). Note that the index returned if from the <strong>sorted</strong>
54 * list, and not from the original one.
55 * @return int index in the full list
56 */
57 public final int getListIndex()
58 {
59 return this.listIndex;
60 }
61
62 /**
63 * Get the object representing the current row.
64 * @return Object
65 */
66 public final Object getCurrentRowObject()
67 {
68 return this.currentRowObject;
69 }
70
71 /**
72 * Initialize the current row. Note this method is also called when sorting a table using a property supplied by the
73 * table decorator, so the method could be called multiple times during rendering. When used to initialize sorting
74 * the method is always called with 0, 0 as currentViewIndex and currentListIndex.
75 * @param rowObject object representing the current row
76 * @param currentViewIndex int index in the displayed list
77 * @param currentListIndex int index in the original list
78 */
79 public final void initRow(Object rowObject, int currentViewIndex, int currentListIndex)
80 {
81 this.currentRowObject = rowObject;
82 this.viewIndex = currentViewIndex;
83 this.listIndex = currentListIndex;
84 }
85
86 /**
87 * Called at the beginning of a row. Can be subclassed to provide specific data at the beginning of a row
88 * @return null in the default implementation
89 */
90 public String startRow()
91 {
92 return null;
93 }
94
95 /**
96 * Called at the end of a row. Can be subclassed to provide specific data at the end of a row
97 * @return null in the default implementation
98 */
99 public String finishRow()
100 {
101 return null;
102 }
103
104 /**
105 * Called at the end of evaluation. Can be subclassed to eventully clean up data. Always remember to also call
106 * super.finish()!
107 */
108 public void finish()
109 {
110 this.currentRowObject = null;
111 super.finish();
112 }
113
114 /**
115 * Call back to add an additional row class to the current row.
116 * @return CSS class attribute value for the current row
117 * @since 1.1
118 */
119 public String addRowClass()
120 {
121 return null;
122 }
123
124 /**
125 * Call back to allow setting an "id" attribute on a row.
126 * @return HTML id attribute value for the current row
127 * @since 1.1
128 */
129 public String addRowId()
130 {
131 return null;
132 }
133
134 /**
135 * Indicates that we are begining a new group.
136 * @param value of the current cell
137 * @param group number of the current column
138 */
139 public void startOfGroup(String value, int group)
140 {
141 }
142
143 /**
144 * Called at the end of a group. Can be subclassed to provide specific data at the end of a row.
145 * @param value of the current cell
146 * @param groupThatHasEnded number of the current column
147 */
148 public void endOfGroup(String value, int groupThatHasEnded)
149 {
150 }
151
152 /**
153 * What value should I display in this cell? The default value for grouped columns is to not display any value if
154 * the cellValue has not changed on an interior iteration. Only invoked for columns that are grouped.
155 * @param cellValue
156 * @param groupingStatus
157 * @return the value to display
158 */
159 public String displayGroupedValue(String cellValue, short groupingStatus, int columnNumber)
160 {
161 if (groupingStatus == TableWriterTemplate.GROUP_END || groupingStatus == TableWriterTemplate.GROUP_NO_CHANGE)
162 {
163 return TagConstants.EMPTY_STRING;
164 }
165 else
166 {
167 return cellValue;
168 }
169 }
170
171 public boolean isLastRow()
172 {
173 return getListIndex() == this.tableModel.getRowListPage().size() - 1;
174 }
175
176 /**
177 * Shortcut for evaluating properties in the current row object. Can be useful for implementing anonymous decorators
178 * in jsp pages without having to know/import the decorated object Class.
179 * @param propertyName property to lookup in current row object. Can also be a nested or indexed property.
180 * @since 1.1
181 */
182 protected Object evaluate(String propertyName)
183 {
184 try
185 {
186 return LookupUtil.getBeanProperty(getCurrentRowObject(), propertyName);
187 }
188 catch (ObjectLookupException e)
189 {
190 return null;
191 }
192 }
193
194 }