1 /*
2 * Copyright (c) 2000, 2020, 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 sun.awt;
27
28 import java.awt.AWTException;
29 import java.awt.BufferCapabilities;
30 import java.awt.Color;
31 import java.awt.Component;
32 import java.awt.Cursor;
33 import java.awt.Dimension;
34 import java.awt.Event;
35 import java.awt.Font;
36 import java.awt.FontMetrics;
37 import java.awt.Graphics;
38 import java.awt.GraphicsConfiguration;
39 import java.awt.Image;
40 import java.awt.Insets;
41 import java.awt.Point;
42 import java.awt.Rectangle;
43 import java.awt.event.FocusEvent.Cause;
44 import java.awt.event.PaintEvent;
45 import java.awt.image.ColorModel;
46 import java.awt.image.VolatileImage;
47 import java.awt.peer.CanvasPeer;
48 import java.awt.peer.ComponentPeer;
49 import java.awt.peer.ContainerPeer;
50 import java.awt.peer.LightweightPeer;
51 import java.awt.peer.PanelPeer;
52
53 import sun.java2d.pipe.Region;
54
55 /**
56 * Implements the LightweightPeer interface for use in lightweight components
57 * that have no native window associated with them. This gets created by
58 * default in Component so that Component and Container can be directly
59 * extended to create useful components written entirely in java. These
60 * components must be hosted somewhere higher up in the component tree by a
61 * native container (such as a Frame).
62 *
63 * This implementation provides no useful semantics and serves only as a
64 * marker. One could provide alternative implementations in java that do
65 * something useful for some of the other peer interfaces to minimize the
66 * native code.
67 *
68 * This was renamed from java.awt.LightweightPeer (a horrible and confusing
69 * name) and moved from java.awt.Toolkit into sun.awt as a public class in
70 * its own file.
71 *
72 * @author Timothy Prinzing
73 * @author Michael Martak
74 */
75 public class NullComponentPeer implements LightweightPeer,
76 CanvasPeer, PanelPeer {
77
78 public boolean isObscured() {
79 return false;
80 }
81
82 public boolean canDetermineObscurity() {
83 return false;
84 }
85
86 public boolean isFocusable() {
87 return false;
88 }
89
90 public void setVisible(boolean b) {
91 }
92
93 public void show() {
94 }
95
96 public void hide() {
97 }
98
99 public void setEnabled(boolean b) {
100 }
101
102 public void enable() {
103 }
104
105 public void disable() {
106 }
107
108 public void paint(Graphics g) {
109 }
110
111 public void repaint(long tm, int x, int y, int width, int height) {
112 }
113
114 public void print(Graphics g) {
115 }
116
117 public void setBounds(int x, int y, int width, int height, int op) {
118 }
119
120 public void reshape(int x, int y, int width, int height) {
121 }
122
123 public void coalescePaintEvent(PaintEvent e) {
124 }
125
126 @SuppressWarnings("deprecation")
127 public boolean handleEvent(Event e) {
128 return false;
129 }
130
131 public void handleEvent(java.awt.AWTEvent arg0) {
132 }
133
134 public Dimension getPreferredSize() {
135 return new Dimension(1,1);
136 }
137
138 public Dimension getMinimumSize() {
139 return new Dimension(1,1);
140 }
141
142 public ColorModel getColorModel() {
143 return null;
144 }
145
146 public Graphics getGraphics() {
147 return null;
148 }
149
150 public GraphicsConfiguration getGraphicsConfiguration() {
151 return null;
152 }
153
154 public FontMetrics getFontMetrics(Font font) {
155 return null;
156 }
157
158 public void dispose() {
159 // no native code
160 }
161
162 public void setForeground(Color c) {
163 }
164
165 public void setBackground(Color c) {
166 }
167
168 public void setFont(Font f) {
169 }
170
171 public void updateCursorImmediately() {
172 }
173
174 public void setCursor(Cursor cursor) {
175 }
176
177 public boolean requestFocus
178 (Component lightweightChild, boolean temporary,
179 boolean focusedWindowChangeAllowed, long time, Cause cause) {
180 return false;
181 }
182
183 public Image createImage(int width, int height) {
184 return null;
185 }
186
187 public Dimension preferredSize() {
188 return getPreferredSize();
189 }
190
191 public Dimension minimumSize() {
192 return getMinimumSize();
193 }
194
195 public Point getLocationOnScreen() {
196 return new Point(0,0);
197 }
198
199 public Insets getInsets() {
200 return insets();
201 }
202
203 public void beginValidate() {
204 }
205
206 public void endValidate() {
207 }
208
209 public Insets insets() {
210 return new Insets(0, 0, 0, 0);
211 }
212
213 public boolean isPaintPending() {
214 return false;
215 }
216
217 public boolean handlesWheelScrolling() {
218 return false;
219 }
220
221 public VolatileImage createVolatileImage(int width, int height) {
222 return null;
223 }
224
225 public void beginLayout() {
226 }
227
228 public void endLayout() {
229 }
230
231 public void createBuffers(int numBuffers, BufferCapabilities caps)
232 throws AWTException {
233 throw new AWTException(
234 "Page-flipping is not allowed on a lightweight component");
235 }
236 public Image getBackBuffer() {
237 throw new IllegalStateException(
238 "Page-flipping is not allowed on a lightweight component");
239 }
240 public void flip(int x1, int y1, int x2, int y2,
241 BufferCapabilities.FlipContents flipAction)
242 {
243 throw new IllegalStateException(
244 "Page-flipping is not allowed on a lightweight component");
245 }
246 public void destroyBuffers() {
247 }
248
249 /**
250 * @see java.awt.peer.ComponentPeer#isReparentSupported
251 */
252 public boolean isReparentSupported() {
253 return false;
254 }
255
256 /**
257 * @see java.awt.peer.ComponentPeer#reparent
258 */
259 public void reparent(ContainerPeer newNativeParent) {
260 throw new UnsupportedOperationException();
261 }
262
263 public void layout() {
264 }
265
266 public Rectangle getBounds() {
267 return new Rectangle(0, 0, 0, 0);
268 }
269
270
271 /**
272 * Applies the shape to the native component window.
273 * @since 1.7
274 */
275 public void applyShape(Region shape) {
276 }
277
278 /**
279 * Lowers this component at the bottom of the above HW peer. If the above parameter
280 * is null then the method places this component at the top of the Z-order.
281 */
282 public void setZOrder(ComponentPeer above) {
283 }
284
285 public boolean updateGraphicsData(GraphicsConfiguration gc) {
286 return false;
287 }
288
289 public GraphicsConfiguration getAppropriateGraphicsConfiguration(
290 GraphicsConfiguration gc)
291 {
292 return gc;
293 }
294 }