1 ////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code for adherence to a set of rules.
3 // Copyright (C) 2001-2019 the original author or authors.
4 //
5 // This library is free software; you can redistribute it and/or
6 // modify it under the terms of the GNU Lesser General Public
7 // License as published by the Free Software Foundation; either
8 // version 2.1 of the License, or (at your option) any later version.
9 //
10 // This library is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 // Lesser General Public License for more details.
14 //
15 // You should have received a copy of the GNU Lesser General Public
16 // License along with this library; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 ////////////////////////////////////////////////////////////////////////////////
19
20 package com.puppycrawl.tools.checkstyle.gui;
21
22 import javax.swing.ListSelectionModel;
23 import javax.swing.tree.DefaultTreeSelectionModel;
24 import javax.swing.tree.TreePath;
25
26 /**
27 * ListToTreeSelectionModelWrapper extends DefaultTreeSelectionModel
28 * to listen for changes in the ListSelectionModel it maintains. Once
29 * a change in the ListSelectionModel happens, the paths are updated
30 * in the DefaultTreeSelectionModel.
31 *
32 */
33 class ListToTreeSelectionModelWrapper extends DefaultTreeSelectionModel {
34
35 private static final long serialVersionUID = 2267930983939339510L;
36 /** TreeTable to perform updates on. */
37 private final TreeTable treeTable;
38 /** Set to true when we are updating the ListSelectionModel. */
39 private boolean updatingListSelectionModel;
40
41 /**
42 * Constructor to initialise treeTable.
43 * @param jTreeTable TreeTable to perform updates on.
44 */
45 /* package */ ListToTreeSelectionModelWrapper(TreeTable jTreeTable) {
46 treeTable = jTreeTable;
47 getListSelectionModel().addListSelectionListener(event -> {
48 updateSelectedPathsFromSelectedRows();
49 });
50 }
51
52 /**
53 * Returns the list selection model. ListToTreeSelectionModelWrapper
54 * listens for changes to this model and updates the selected paths
55 * accordingly.
56 *
57 * @return the list selection model
58 */
59 protected final ListSelectionModel getListSelectionModel() {
60 return listSelectionModel;
61 }
62
63 /**
64 * This is overridden to set {@code updatingListSelectionModel}
65 * and message super. This is the only place DefaultTreeSelectionModel
66 * alters the ListSelectionModel.
67 */
68 @Override
69 public void resetRowSelection() {
70 if (!updatingListSelectionModel) {
71 updatingListSelectionModel = true;
72 try {
73 super.resetRowSelection();
74 }
75 finally {
76 updatingListSelectionModel = false;
77 }
78 }
79 // Notice how we don't message super if
80 // updatingListSelectionModel is true. If
81 // updatingListSelectionModel is true, it implies the
82 // ListSelectionModel has already been updated and the
83 // paths are the only thing that needs to be updated.
84 }
85
86 /**
87 * If {@code updatingListSelectionModel} is false, this will
88 * reset the selected paths from the selected rows in the list
89 * selection model.
90 */
91 private void updateSelectedPathsFromSelectedRows() {
92 if (!updatingListSelectionModel) {
93 updatingListSelectionModel = true;
94 try {
95 // This is way expensive, ListSelectionModel needs an
96 // enumerator for iterating.
97 final int min = listSelectionModel.getMinSelectionIndex();
98 final int max = listSelectionModel.getMaxSelectionIndex();
99
100 clearSelection();
101 if (min != -1 && max != -1) {
102 for (int counter = min; counter <= max; counter++) {
103 updateSelectedPathIfRowIsSelected(counter);
104 }
105 }
106 }
107 finally {
108 updatingListSelectionModel = false;
109 }
110 }
111 }
112
113 /**
114 * If the row at given index is selected, selected paths are updated.
115 * @param counter number of row.
116 */
117 private void updateSelectedPathIfRowIsSelected(int counter) {
118 if (listSelectionModel.isSelectedIndex(counter)) {
119 final TreePath selPath = treeTable.getTree().getPathForRow(counter);
120
121 if (selPath != null) {
122 addSelectionPath(selPath);
123 }
124 }
125 }
126
127 }