J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2002 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | package javax.swing; |
| 26 | |
| 27 | import java.awt.FocusTraversalPolicy; |
| 28 | import java.awt.Component; |
| 29 | import java.awt.Container; |
| 30 | import java.awt.Window; |
| 31 | import java.util.HashMap; |
| 32 | import java.util.HashSet; |
| 33 | import java.io.*; |
| 34 | |
| 35 | |
| 36 | /** |
| 37 | * A FocusTraversalPolicy which provides support for legacy applications which |
| 38 | * handle focus traversal via JComponent.setNextFocusableComponent or by |
| 39 | * installing a custom DefaultFocusManager. If a specific traversal has not |
| 40 | * been hard coded, then that traversal is provided either by the custom |
| 41 | * DefaultFocusManager, or by a wrapped FocusTraversalPolicy instance. |
| 42 | * |
| 43 | * @author David Mendenhall |
| 44 | */ |
| 45 | final class LegacyGlueFocusTraversalPolicy extends FocusTraversalPolicy |
| 46 | implements Serializable |
| 47 | { |
| 48 | private transient FocusTraversalPolicy delegatePolicy; |
| 49 | private transient DefaultFocusManager delegateManager; |
| 50 | |
| 51 | private HashMap forwardMap = new HashMap(), |
| 52 | backwardMap = new HashMap(); |
| 53 | |
| 54 | LegacyGlueFocusTraversalPolicy(FocusTraversalPolicy delegatePolicy) { |
| 55 | this.delegatePolicy = delegatePolicy; |
| 56 | } |
| 57 | LegacyGlueFocusTraversalPolicy(DefaultFocusManager delegateManager) { |
| 58 | this.delegateManager = delegateManager; |
| 59 | } |
| 60 | |
| 61 | void setNextFocusableComponent(Component left, Component right) { |
| 62 | forwardMap.put(left, right); |
| 63 | backwardMap.put(right, left); |
| 64 | } |
| 65 | void unsetNextFocusableComponent(Component left, Component right) { |
| 66 | forwardMap.remove(left); |
| 67 | backwardMap.remove(right); |
| 68 | } |
| 69 | |
| 70 | public Component getComponentAfter(Container focusCycleRoot, |
| 71 | Component aComponent) { |
| 72 | Component hardCoded = aComponent, prevHardCoded; |
| 73 | HashSet sanity = new HashSet(); |
| 74 | |
| 75 | do { |
| 76 | prevHardCoded = hardCoded; |
| 77 | hardCoded = (Component)forwardMap.get(hardCoded); |
| 78 | if (hardCoded == null) { |
| 79 | if (delegatePolicy != null && |
| 80 | prevHardCoded.isFocusCycleRoot(focusCycleRoot)) { |
| 81 | return delegatePolicy.getComponentAfter(focusCycleRoot, |
| 82 | prevHardCoded); |
| 83 | } else if (delegateManager != null) { |
| 84 | return delegateManager. |
| 85 | getComponentAfter(focusCycleRoot, aComponent); |
| 86 | } else { |
| 87 | return null; |
| 88 | } |
| 89 | } |
| 90 | if (sanity.contains(hardCoded)) { |
| 91 | // cycle detected; bail |
| 92 | return null; |
| 93 | } |
| 94 | sanity.add(hardCoded); |
| 95 | } while (!accept(hardCoded)); |
| 96 | |
| 97 | return hardCoded; |
| 98 | } |
| 99 | public Component getComponentBefore(Container focusCycleRoot, |
| 100 | Component aComponent) { |
| 101 | Component hardCoded = aComponent, prevHardCoded; |
| 102 | HashSet sanity = new HashSet(); |
| 103 | |
| 104 | do { |
| 105 | prevHardCoded = hardCoded; |
| 106 | hardCoded = (Component)backwardMap.get(hardCoded); |
| 107 | if (hardCoded == null) { |
| 108 | if (delegatePolicy != null && |
| 109 | prevHardCoded.isFocusCycleRoot(focusCycleRoot)) { |
| 110 | return delegatePolicy.getComponentBefore(focusCycleRoot, |
| 111 | prevHardCoded); |
| 112 | } else if (delegateManager != null) { |
| 113 | return delegateManager. |
| 114 | getComponentBefore(focusCycleRoot, aComponent); |
| 115 | } else { |
| 116 | return null; |
| 117 | } |
| 118 | } |
| 119 | if (sanity.contains(hardCoded)) { |
| 120 | // cycle detected; bail |
| 121 | return null; |
| 122 | } |
| 123 | sanity.add(hardCoded); |
| 124 | } while (!accept(hardCoded)); |
| 125 | |
| 126 | return hardCoded; |
| 127 | } |
| 128 | public Component getFirstComponent(Container focusCycleRoot) { |
| 129 | if (delegatePolicy != null) { |
| 130 | return delegatePolicy.getFirstComponent(focusCycleRoot); |
| 131 | } else if (delegateManager != null) { |
| 132 | return delegateManager.getFirstComponent(focusCycleRoot); |
| 133 | } else { |
| 134 | return null; |
| 135 | } |
| 136 | } |
| 137 | public Component getLastComponent(Container focusCycleRoot) { |
| 138 | if (delegatePolicy != null) { |
| 139 | return delegatePolicy.getLastComponent(focusCycleRoot); |
| 140 | } else if (delegateManager != null) { |
| 141 | return delegateManager.getLastComponent(focusCycleRoot); |
| 142 | } else { |
| 143 | return null; |
| 144 | } |
| 145 | } |
| 146 | public Component getDefaultComponent(Container focusCycleRoot) { |
| 147 | if (delegatePolicy != null) { |
| 148 | return delegatePolicy.getDefaultComponent(focusCycleRoot); |
| 149 | } else { |
| 150 | return getFirstComponent(focusCycleRoot); |
| 151 | } |
| 152 | } |
| 153 | private boolean accept(Component aComponent) { |
| 154 | if (!(aComponent.isVisible() && aComponent.isDisplayable() && |
| 155 | aComponent.isFocusable() && aComponent.isEnabled())) { |
| 156 | return false; |
| 157 | } |
| 158 | |
| 159 | // Verify that the Component is recursively enabled. Disabling a |
| 160 | // heavyweight Container disables its children, whereas disabling |
| 161 | // a lightweight Container does not. |
| 162 | if (!(aComponent instanceof Window)) { |
| 163 | for (Container enableTest = aComponent.getParent(); |
| 164 | enableTest != null; |
| 165 | enableTest = enableTest.getParent()) |
| 166 | { |
| 167 | if (!(enableTest.isEnabled() || enableTest.isLightweight())) { |
| 168 | return false; |
| 169 | } |
| 170 | if (enableTest instanceof Window) { |
| 171 | break; |
| 172 | } |
| 173 | } |
| 174 | } |
| 175 | |
| 176 | return true; |
| 177 | } |
| 178 | private void writeObject(ObjectOutputStream out) throws IOException { |
| 179 | out.defaultWriteObject(); |
| 180 | |
| 181 | if (delegatePolicy instanceof Serializable) { |
| 182 | out.writeObject(delegatePolicy); |
| 183 | } else { |
| 184 | out.writeObject(null); |
| 185 | } |
| 186 | |
| 187 | if (delegateManager instanceof Serializable) { |
| 188 | out.writeObject(delegateManager); |
| 189 | } else { |
| 190 | out.writeObject(null); |
| 191 | } |
| 192 | } |
| 193 | private void readObject(ObjectInputStream in) |
| 194 | throws IOException, ClassNotFoundException |
| 195 | { |
| 196 | in.defaultReadObject(); |
| 197 | delegatePolicy = (FocusTraversalPolicy)in.readObject(); |
| 198 | delegateManager = (DefaultFocusManager)in.readObject(); |
| 199 | } |
| 200 | } |