1 |
14 |
jlechner |
/* GraphicsEnvironment.java -- information about the graphics environment
|
2 |
|
|
Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
|
3 |
|
|
|
4 |
|
|
This file is part of GNU Classpath.
|
5 |
|
|
|
6 |
|
|
GNU Classpath is free software; you can redistribute it and/or modify
|
7 |
|
|
it under the terms of the GNU General Public License as published by
|
8 |
|
|
the Free Software Foundation; either version 2, or (at your option)
|
9 |
|
|
any later version.
|
10 |
|
|
|
11 |
|
|
GNU Classpath is distributed in the hope that it will be useful, but
|
12 |
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
13 |
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
14 |
|
|
General Public License for more details.
|
15 |
|
|
|
16 |
|
|
You should have received a copy of the GNU General Public License
|
17 |
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
18 |
|
|
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
19 |
|
|
02110-1301 USA.
|
20 |
|
|
|
21 |
|
|
Linking this library statically or dynamically with other modules is
|
22 |
|
|
making a combined work based on this library. Thus, the terms and
|
23 |
|
|
conditions of the GNU General Public License cover the whole
|
24 |
|
|
combination.
|
25 |
|
|
|
26 |
|
|
As a special exception, the copyright holders of this library give you
|
27 |
|
|
permission to link this library with independent modules to produce an
|
28 |
|
|
executable, regardless of the license terms of these independent
|
29 |
|
|
modules, and to copy and distribute the resulting executable under
|
30 |
|
|
terms of your choice, provided that you also meet, for each linked
|
31 |
|
|
independent module, the terms and conditions of the license of that
|
32 |
|
|
module. An independent module is a module which is not derived from
|
33 |
|
|
or based on this library. If you modify this library, you may extend
|
34 |
|
|
this exception to your version of the library, but you are not
|
35 |
|
|
obligated to do so. If you do not wish to do so, delete this
|
36 |
|
|
exception statement from your version. */
|
37 |
|
|
|
38 |
|
|
|
39 |
|
|
package java.awt;
|
40 |
|
|
|
41 |
|
|
import gnu.java.awt.ClasspathToolkit;
|
42 |
|
|
import gnu.classpath.SystemProperties;
|
43 |
|
|
import java.awt.image.BufferedImage;
|
44 |
|
|
import java.util.Locale;
|
45 |
|
|
|
46 |
|
|
/**
|
47 |
|
|
* This descibes the collection of GraphicsDevice and Font objects available
|
48 |
|
|
* on a given platform. The resources might be local or remote, and specify
|
49 |
|
|
* the valid configurations for displaying graphics.
|
50 |
|
|
*
|
51 |
|
|
* @author Eric Blake (ebb9@email.byu.edu)
|
52 |
|
|
* @see GraphicsDevice
|
53 |
|
|
* @see GraphicsConfiguration
|
54 |
|
|
* @since 1.4
|
55 |
|
|
* @status updated to 1.4
|
56 |
|
|
*/
|
57 |
|
|
public abstract class GraphicsEnvironment
|
58 |
|
|
{
|
59 |
|
|
private static GraphicsEnvironment localGraphicsEnvironment;
|
60 |
|
|
|
61 |
|
|
/**
|
62 |
|
|
* The environment must be obtained from a factory or query method, hence
|
63 |
|
|
* this constructor is protected.
|
64 |
|
|
*/
|
65 |
|
|
protected GraphicsEnvironment()
|
66 |
|
|
{
|
67 |
|
|
}
|
68 |
|
|
|
69 |
|
|
/**
|
70 |
|
|
* Returns the local graphics environment. If the java.awt.graphicsenv
|
71 |
|
|
* system property is set, it instantiates the specified class,
|
72 |
|
|
* otherwise it assume that the awt toolkit is a ClasspathToolkit
|
73 |
|
|
* and delegates to it to create the instance.
|
74 |
|
|
*
|
75 |
|
|
* @return the local environment
|
76 |
|
|
*/
|
77 |
|
|
public static GraphicsEnvironment getLocalGraphicsEnvironment()
|
78 |
|
|
{
|
79 |
|
|
if (localGraphicsEnvironment != null)
|
80 |
|
|
return localGraphicsEnvironment;
|
81 |
|
|
|
82 |
|
|
String graphicsenv = SystemProperties.getProperty("java.awt.graphicsenv",
|
83 |
|
|
null);
|
84 |
|
|
if (graphicsenv != null)
|
85 |
|
|
{
|
86 |
|
|
try
|
87 |
|
|
{
|
88 |
|
|
// We intentionally use the bootstrap class loader.
|
89 |
|
|
localGraphicsEnvironment = (GraphicsEnvironment)
|
90 |
|
|
Class.forName(graphicsenv).newInstance();
|
91 |
|
|
return localGraphicsEnvironment;
|
92 |
|
|
}
|
93 |
|
|
catch (Exception x)
|
94 |
|
|
{
|
95 |
|
|
throw (InternalError)
|
96 |
|
|
new InternalError("Unable to instantiate java.awt.graphicsenv")
|
97 |
|
|
.initCause(x);
|
98 |
|
|
}
|
99 |
|
|
}
|
100 |
|
|
else
|
101 |
|
|
{
|
102 |
|
|
ClasspathToolkit tk;
|
103 |
|
|
tk = ((ClasspathToolkit) Toolkit.getDefaultToolkit());
|
104 |
|
|
localGraphicsEnvironment = tk.getLocalGraphicsEnvironment();
|
105 |
|
|
return localGraphicsEnvironment;
|
106 |
|
|
}
|
107 |
|
|
}
|
108 |
|
|
|
109 |
|
|
/**
|
110 |
|
|
* Check if the local environment is headless, meaning that it does not
|
111 |
|
|
* support a display, keyboard, or mouse. Many methods in the Abstract
|
112 |
|
|
* Windows Toolkit (java.awt) throw a {@link HeadlessException} if this
|
113 |
|
|
* returns true.
|
114 |
|
|
*
|
115 |
|
|
* This method returns true if the java.awt.headless property is set
|
116 |
|
|
* to "true".
|
117 |
|
|
*
|
118 |
|
|
* @return true if the environment is headless, meaning that graphics are
|
119 |
|
|
* unsupported
|
120 |
|
|
* @since 1.4
|
121 |
|
|
*/
|
122 |
|
|
public static boolean isHeadless()
|
123 |
|
|
{
|
124 |
|
|
String headless = SystemProperties.getProperty("java.awt.headless", null);
|
125 |
|
|
return "true".equalsIgnoreCase(headless);
|
126 |
|
|
}
|
127 |
|
|
|
128 |
|
|
/**
|
129 |
|
|
* Check if the given environment is headless, meaning that it does not
|
130 |
|
|
* support a display, keyboard, or mouse. Many methods in the Abstract
|
131 |
|
|
* Windows Toolkit (java.awt) throw a {@link HeadlessException} if this
|
132 |
|
|
* returns true. This default implementation returns isHeadless(), so
|
133 |
|
|
* subclasses need only override it if they differ.
|
134 |
|
|
*
|
135 |
|
|
* @return true if the environment is headless, meaning that graphics are
|
136 |
|
|
* unsupported
|
137 |
|
|
* @since 1.4
|
138 |
|
|
*/
|
139 |
|
|
public boolean isHeadlessInstance()
|
140 |
|
|
{
|
141 |
|
|
return isHeadless();
|
142 |
|
|
}
|
143 |
|
|
|
144 |
|
|
/**
|
145 |
|
|
* Get an array of all the GraphicsDevice objects.
|
146 |
|
|
*
|
147 |
|
|
* @return the available graphics devices, may be 0 length
|
148 |
|
|
* @throws HeadlessException if the environment is headless
|
149 |
|
|
*/
|
150 |
|
|
public abstract GraphicsDevice[] getScreenDevices();
|
151 |
|
|
|
152 |
|
|
/**
|
153 |
|
|
* Get the default screen GraphicsDevice object.
|
154 |
|
|
*
|
155 |
|
|
* @return the default screen device
|
156 |
|
|
* @throws HeadlessException if the environment is headless
|
157 |
|
|
*/
|
158 |
|
|
public abstract GraphicsDevice getDefaultScreenDevice();
|
159 |
|
|
|
160 |
|
|
/**
|
161 |
|
|
* Return a Graphics2D object which will render into the specified image.
|
162 |
|
|
*
|
163 |
|
|
* @param image the image to render into
|
164 |
|
|
* @return the object that renders into the image
|
165 |
|
|
*/
|
166 |
|
|
public abstract Graphics2D createGraphics(BufferedImage image);
|
167 |
|
|
|
168 |
|
|
/**
|
169 |
|
|
* Returns an array of the one-point size fonts available in this
|
170 |
|
|
* environment. From there, the user can select the font and derive the
|
171 |
|
|
* correct one of proper size and attributes, using <code>deriveFont</code>.
|
172 |
|
|
* Only one master version of each font appears in this array; if a font
|
173 |
|
|
* can be derived from another, it must be created in that way.
|
174 |
|
|
*
|
175 |
|
|
* @return the array of available fonts
|
176 |
|
|
* @see #getAvailableFontFamilyNames()
|
177 |
|
|
* @see Font#deriveFont(int, float)
|
178 |
|
|
* @since 1.2
|
179 |
|
|
*/
|
180 |
|
|
public abstract Font[] getAllFonts();
|
181 |
|
|
|
182 |
|
|
/**
|
183 |
|
|
* Returns an array of the font family names available in this environment.
|
184 |
|
|
* This allows flexibility in choosing the style of font, while still letting
|
185 |
|
|
* the Font class decide its best match.
|
186 |
|
|
*
|
187 |
|
|
* @return the array of available font families
|
188 |
|
|
* @see #getAllFonts()
|
189 |
|
|
* @see Font#getFamily()
|
190 |
|
|
* @since 1.2
|
191 |
|
|
*/
|
192 |
|
|
public abstract String[] getAvailableFontFamilyNames();
|
193 |
|
|
|
194 |
|
|
/**
|
195 |
|
|
* Returns an array of the font family names available in this environment,
|
196 |
|
|
* localized to the current Locale if l is non-null. This allows
|
197 |
|
|
* flexibility in choosing the style of font, while still letting the Font
|
198 |
|
|
* class decide its best match.
|
199 |
|
|
*
|
200 |
|
|
* @param l the locale to use
|
201 |
|
|
* @return the array of available font families, localized
|
202 |
|
|
* @see #getAllFonts()
|
203 |
|
|
* @see Font#getFamily()
|
204 |
|
|
* @since 1.2
|
205 |
|
|
*/
|
206 |
|
|
public abstract String[] getAvailableFontFamilyNames(Locale l);
|
207 |
|
|
|
208 |
|
|
/**
|
209 |
|
|
* Returns the point where a window should be centered. You should probably
|
210 |
|
|
* also check that the window fits within the screen bounds. The default
|
211 |
|
|
* simply returns the center of the maximum window bounds; subclasses should
|
212 |
|
|
* override this if native objects (like scrollbars) make that off-centered.
|
213 |
|
|
*
|
214 |
|
|
* @return the centering point
|
215 |
|
|
* @throws HeadlessException if the environment is headless
|
216 |
|
|
* @see #getMaximumWindowBounds()
|
217 |
|
|
* @since 1.4
|
218 |
|
|
*/
|
219 |
|
|
public Point getCenterPoint()
|
220 |
|
|
{
|
221 |
|
|
Rectangle r = getMaximumWindowBounds();
|
222 |
|
|
return new Point(r.x + r.width / 2, r.y + r.height / 2);
|
223 |
|
|
}
|
224 |
|
|
|
225 |
|
|
/**
|
226 |
|
|
* Returns the maximum bounds for a centered window object. The default
|
227 |
|
|
* implementation simply returns the bounds of the default configuration
|
228 |
|
|
* of the default screen; subclasses should override this to if native
|
229 |
|
|
* objects (like scrollbars) reduce what is truly available. Also,
|
230 |
|
|
* subclasses should override this if the window should be centered across
|
231 |
|
|
* a multi-screen display.
|
232 |
|
|
*
|
233 |
|
|
* @return the maximum window bounds
|
234 |
|
|
* @throws HeadlessException if the environment is headless
|
235 |
|
|
* @see #getCenterPoint()
|
236 |
|
|
* @see GraphicsConfiguration#getBounds()
|
237 |
|
|
* @see Toolkit#getScreenInsets(GraphicsConfiguration)
|
238 |
|
|
* @since 1.4
|
239 |
|
|
*/
|
240 |
|
|
public Rectangle getMaximumWindowBounds()
|
241 |
|
|
{
|
242 |
|
|
return getDefaultScreenDevice().getDefaultConfiguration().getBounds();
|
243 |
|
|
}
|
244 |
|
|
} // class GraphicsEnvironment
|