1 /*
2 * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javafx.scene.control.cell;
27
28 import javafx.beans.NamedArg;
29 import javafx.beans.property.Property;
30 import javafx.beans.property.ReadOnlyObjectWrapper;
31 import javafx.beans.value.ObservableValue;
32 import javafx.scene.control.TreeItem;
33 import javafx.scene.control.TreeTableColumn;
34 import javafx.scene.control.TreeTableColumn.CellDataFeatures;
35 import javafx.util.Callback;
36 import com.sun.javafx.property.PropertyReference;
37 import com.sun.javafx.scene.control.Logging;
38 import sun.util.logging.PlatformLogger;
39 import sun.util.logging.PlatformLogger.Level;
40
41
42 /**
43 * A convenience implementation of the Callback interface, designed specifically
44 * for use within the {@link TreeTableColumn}
45 * {@link TreeTableColumn#cellValueFactoryProperty() cell value factory}. An example
46 * of how to use this class is:
47 *
48 * <pre><code>
49 * TreeTableColumn<Person,String> firstNameCol = new TreeTableColumn<Person,String>("First Name");
50 * firstNameCol.setCellValueFactory(new TreeItemPropertyValueFactory<Person,String>("firstName"));
51 * </code></pre>
52 *
53 * In this example, the "firstName" string is used as a reference to an assumed
54 * <code>firstNameProperty()</code> method in the <code>Person</code> class type
55 * (which is the class type of the TreeTableView). Additionally, this method must
56 * return a {@link Property} instance. If a method meeting these requirements
57 * is found, then the {@link javafx.scene.control.TreeTableCell} is populated
58 * with this {@literal ObservableValue<T>}.
59 * In addition, the TreeTableView will automatically add an observer to the
60 * returned value, such that any changes fired will be observed by the TreeTableView,
61 * resulting in the cell immediately updating.
62 *
63 * <p>If no method matching this pattern exists, there is fall-through support
64 * for attempting to call get<property>() or is<property>() (that is,
65 * <code>getFirstName()</code> or <code>isFirstName()</code> in the example
66 * above). If a method matching this pattern exists, the value returned from this method
67 * is wrapped in a {@link ReadOnlyObjectWrapper} and returned to the TreeTableCell.
68 * However, in this situation, this means that the TreeTableCell will not be able
69 * to observe the ObservableValue for changes (as is the case in the first
70 * approach above).
71 *
72 * <p>For reference (and as noted in the TreeTableColumn
73 * {@link TreeTableColumn#cellValueFactory cell value factory} documentation), the
74 * long form of the code above would be the following:
75 *
76 * <pre><code>
77 * TreeTableColumn<Person,String> firstNameCol = new TreeTableColumn<Person,String>("First Name");
78 * {@literal
79 * firstNameCol.setCellValueFactory(new Callback<CellDataFeatures<Person, String>, ObservableValue<String>>() {
80 * public ObservableValue<String> call(CellDataFeatures<Person, String> p) {
81 * // p.getValue() returns the TreeItem<Person> instance for a particular
82 * // TreeTableView row, and the second getValue() call returns the
83 * // Person instance contained within the TreeItem.
84 * return p.getValue().getValue().firstNameProperty();
85 * }
86 * });
87 * }
88 * }
89 * </code></pre>
90 *
91 * @see TreeTableColumn
92 * @see javafx.scene.control.TreeTableView
93 * @see javafx.scene.control.TreeTableCell
94 * @see PropertyValueFactory
95 * @see MapValueFactory
96 * @since JavaFX 8.0
97 */
98 public class TreeItemPropertyValueFactory<S,T> implements Callback<TreeTableColumn.CellDataFeatures<S,T>, ObservableValue<T>> {
99
100 private final String property;
101
102 private Class<?> columnClass;
103 private String previousProperty;
104 private PropertyReference<T> propertyRef;
105
106 /**
107 * Creates a default PropertyValueFactory to extract the value from a given
108 * TableView row item reflectively, using the given property name.
109 *
110 * @param property The name of the property with which to attempt to
111 * reflectively extract a corresponding value for in a given object.
112 */
113 public TreeItemPropertyValueFactory(@NamedArg("property") String property) {
114 this.property = property;
115 }
116
117 /** {@inheritDoc} */
118 @Override public ObservableValue<T> call(CellDataFeatures<S, T> param) {
119 TreeItem<S> treeItem = param.getValue();
120 return getCellDataReflectively(treeItem.getValue());
121 }
122
123 /**
124 * Returns the property name provided in the constructor.
125 * @return the property name provided in the constructor
126 */
127 public final String getProperty() { return property; }
128
129 private ObservableValue<T> getCellDataReflectively(S rowData) {
130 if (getProperty() == null || getProperty().isEmpty() || rowData == null) return null;
131
132 try {
133 // we attempt to cache the property reference here, as otherwise
134 // performance suffers when working in large data models. For
135 // a bit of reference, refer to RT-13937.
136 if (columnClass == null || previousProperty == null ||
137 ! columnClass.equals(rowData.getClass()) ||
138 ! previousProperty.equals(getProperty())) {
139
140 // create a new PropertyReference
141 this.columnClass = rowData.getClass();
142 this.previousProperty = getProperty();
143 this.propertyRef = new PropertyReference<T>(rowData.getClass(), getProperty());
144 }
145
146 return propertyRef.getProperty(rowData);
147 } catch (IllegalStateException e) {
148 try {
149 // attempt to just get the value
150 T value = propertyRef.get(rowData);
151 return new ReadOnlyObjectWrapper<T>(value);
152 } catch (IllegalStateException e2) {
153 // fall through to logged exception below
154 }
155
156 // log the warning and move on
157 final PlatformLogger logger = Logging.getControlsLogger();
158 if (logger.isLoggable(Level.WARNING)) {
159 logger.finest("Can not retrieve property '" + getProperty() +
160 "' in TreeItemPropertyValueFactory: " + this +
161 " with provided class type: " + rowData.getClass(), e);
162 }
163 }
164
165 return null;
166 }
167 }