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| 1 | /* | ||
| 2 | * Copyright (c) 1997, 2010, 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 | |||
| 27 | package java.awt; | ||
| 28 | |||
| 29 | import java.awt.image.BufferedImage; | ||
| 30 | import java.security.AccessController; | ||
| 31 | import java.util.Locale; | ||
| 32 | |||
| 33 | import sun.font.FontManager; | ||
| 34 | import sun.font.FontManagerFactory; | ||
| 35 | import sun.java2d.HeadlessGraphicsEnvironment; | ||
| 36 | import sun.java2d.SunGraphicsEnvironment; | ||
| 37 | import sun.security.action.GetPropertyAction; | ||
| 38 | |||
| 39 | /** | ||
| 40 | * | ||
| 41 | * The <code>GraphicsEnvironment</code> class describes the collection | ||
| 42 | * of {@link GraphicsDevice} objects and {@link java.awt.Font} objects | ||
| 43 | * available to a Java(tm) application on a particular platform. | ||
| 44 | * The resources in this <code>GraphicsEnvironment</code> might be local | ||
| 45 | * or on a remote machine. <code>GraphicsDevice</code> objects can be | ||
| 46 | * screens, printers or image buffers and are the destination of | ||
| 47 | * {@link Graphics2D} drawing methods. Each <code>GraphicsDevice</code> | ||
| 48 | * has a number of {@link GraphicsConfiguration} objects associated with | ||
| 49 | * it. These objects specify the different configurations in which the | ||
| 50 | * <code>GraphicsDevice</code> can be used. | ||
| 51 | * @see GraphicsDevice | ||
| 52 | * @see GraphicsConfiguration | ||
| 53 | */ | ||
| 54 | |||
| 55 | public abstract class GraphicsEnvironment { | ||
| 56 | private static GraphicsEnvironment localEnv; | ||
| 57 | |||
| 58 | /** | ||
| 59 | * The headless state of the Toolkit and GraphicsEnvironment | ||
| 60 | */ | ||
| 61 | private static Boolean headless; | ||
| 62 | |||
| 63 | /** | ||
| 64 | * The headless state assumed by default | ||
| 65 | */ | ||
| 66 | private static Boolean defaultHeadless; | ||
| 67 | |||
| 68 | /** | ||
| 69 | * This is an abstract class and cannot be instantiated directly. | ||
| 70 | * Instances must be obtained from a suitable factory or query method. | ||
| 71 | */ | ||
| 72 | protected GraphicsEnvironment() { | ||
| 73 | } | ||
| 74 | |||
| 75 | /** | ||
| 76 | * Returns the local <code>GraphicsEnvironment</code>. | ||
| 77 | * @return the local <code>GraphicsEnvironment</code> | ||
| 78 | */ | ||
| 79 | public static synchronized GraphicsEnvironment getLocalGraphicsEnvironment() { | ||
| 80 | if (localEnv == null) { | ||
| 81 | localEnv = createGE(); | ||
| 82 | } | ||
| 83 | |||
| 84 | return localEnv; | ||
| 85 | } | ||
| 86 | |||
| 87 | /** | ||
| 88 | * Creates and returns the GraphicsEnvironment, according to the | ||
| 89 | * system property 'java.awt.graphicsenv'. | ||
| 90 | * | ||
| 91 | * @return the graphics environment | ||
| 92 | */ | ||
| 93 | private static GraphicsEnvironment createGE() { | ||
| 94 | GraphicsEnvironment ge; | ||
| 95 | String nm = AccessController.doPrivileged(new GetPropertyAction("java.awt.graphicsenv", null)); | ||
| 96 | try { | ||
| 97 | // long t0 = System.currentTimeMillis(); | ||
| 98 | Class geCls; | ||
| 99 | try { | ||
| 100 | // First we try if the bootclassloader finds the requested | ||
| 101 | // class. This way we can avoid to run in a privileged block. | ||
| 102 | geCls = Class.forName(nm); | ||
| 103 | } catch (ClassNotFoundException ex) { | ||
| 104 | // If the bootclassloader fails, we try again with the | ||
| 105 | // application classloader. | ||
| 106 | ClassLoader cl = ClassLoader.getSystemClassLoader(); | ||
| 107 | geCls = Class.forName(nm, true, cl); | ||
| 108 | } | ||
| 109 | ge = (GraphicsEnvironment) geCls.newInstance(); | ||
| 110 | // long t1 = System.currentTimeMillis(); | ||
| 111 | // System.out.println("GE creation took " + (t1-t0)+ "ms."); | ||
| 112 | if (isHeadless()) { | ||
| 113 | ge = new HeadlessGraphicsEnvironment(ge); | ||
| 114 | } | ||
| 115 | } catch (ClassNotFoundException e) { | ||
| 116 | throw new Error("Could not find class: "+nm); | ||
| 117 | } catch (InstantiationException e) { | ||
| 118 | throw new Error("Could not instantiate Graphics Environment: " | ||
| 119 | + nm); | ||
| 120 | } catch (IllegalAccessException e) { | ||
| 121 | throw new Error ("Could not access Graphics Environment: " | ||
| 122 | + nm); | ||
| 123 | } | ||
| 124 | return ge; | ||
| 125 | } | ||
| 126 | |||
| 127 | /** | ||
| 128 | * Tests whether or not a display, keyboard, and mouse can be | ||
| 129 | * supported in this environment. If this method returns true, | ||
| 130 | * a HeadlessException is thrown from areas of the Toolkit | ||
| 131 | * and GraphicsEnvironment that are dependent on a display, | ||
| 132 | * keyboard, or mouse. | ||
| 133 | * @return <code>true</code> if this environment cannot support | ||
| 134 | * a display, keyboard, and mouse; <code>false</code> | ||
| 135 | * otherwise | ||
| 136 | * @see java.awt.HeadlessException | ||
| 137 | * @since 1.4 | ||
| 138 | */ | ||
| 139 | public static boolean isHeadless() { | ||
| 140 | return getHeadlessProperty(); | ||
| 141 | } | ||
| 142 | |||
| 143 | /** | ||
| 144 | * @return warning message if headless state is assumed by default; | ||
| 145 | * null otherwise | ||
| 146 | * @since 1.5 | ||
| 147 | */ | ||
| 148 | static String getHeadlessMessage() { | ||
| 149 | if (headless == null) { | ||
| 150 | getHeadlessProperty(); // initialize the values | ||
| 151 | } | ||
| 152 | return defaultHeadless != Boolean.TRUE ? null : | ||
| 153 | "\nNo X11 DISPLAY variable was set, " + | ||
| 154 | "but this program performed an operation which requires it."; | ||
| 155 | } | ||
| 156 | |||
| 157 | /** | ||
| 158 | * @return the value of the property "java.awt.headless" | ||
| 159 | * @since 1.4 | ||
| 160 | */ | ||
| 161 | private static boolean getHeadlessProperty() { | ||
| 162 | if (headless == null) { | ||
| 163 | java.security.AccessController.doPrivileged( | ||
| 164 | new java.security.PrivilegedAction() { | ||
| 165 | public Object run() { | ||
| 166 | String nm = System.getProperty("java.awt.headless"); | ||
| 167 | |||
| 168 | if (nm == null) { | ||
| 169 | /* No need to ask for DISPLAY when run in a browser */ | ||
| 170 | if (System.getProperty("javaplugin.version") != null) { | ||
| 171 | headless = defaultHeadless = Boolean.FALSE; | ||
| 172 | } else { | ||
| 173 | String osName = System.getProperty("os.name"); | ||
| 174 | headless = defaultHeadless = | ||
| 175 | Boolean.valueOf(("Linux".equals(osName) || "SunOS".equals(osName)) && | ||
| 176 | (System.getenv("DISPLAY") == null)); | ||
| 177 | } | ||
| 178 | } else if (nm.equals("true")) { | ||
| 179 | headless = Boolean.TRUE; | ||
| 180 | } else { | ||
| 181 | headless = Boolean.FALSE; | ||
| 182 | } | ||
| 183 | return null; | ||
| 184 | } | ||
| 185 | } | ||
| 186 | ); | ||
| 187 | } | ||
| 188 | return headless.booleanValue(); | ||
| 189 | } | ||
| 190 | |||
| 191 | /** | ||
| 192 | * Check for headless state and throw HeadlessException if headless | ||
| 193 | * @since 1.4 | ||
| 194 | */ | ||
| 195 | static void checkHeadless() throws HeadlessException { | ||
| 196 | if (isHeadless()) { | ||
| 197 | throw new HeadlessException(); | ||
| 198 | } | ||
| 199 | } | ||
| 200 | |||
| 201 | /** | ||
| 202 | * Returns whether or not a display, keyboard, and mouse can be | ||
| 203 | * supported in this graphics environment. If this returns true, | ||
| 204 | * <code>HeadlessException</code> will be thrown from areas of the | ||
| 205 | * graphics environment that are dependent on a display, keyboard, or | ||
| 206 | * mouse. | ||
| 207 | * @return <code>true</code> if a display, keyboard, and mouse | ||
| 208 | * can be supported in this environment; <code>false</code> | ||
| 209 | * otherwise | ||
| 210 | * @see java.awt.HeadlessException | ||
| 211 | * @see #isHeadless | ||
| 212 | * @since 1.4 | ||
| 213 | */ | ||
| 214 | public boolean isHeadlessInstance() { | ||
| 215 | // By default (local graphics environment), simply check the | ||
| 216 | // headless property. | ||
| 217 | return getHeadlessProperty(); | ||
| 218 | } | ||
| 219 | |||
| 220 | /** | ||
| 221 | * Returns an array of all of the screen <code>GraphicsDevice</code> | ||
| 222 | * objects. | ||
| 223 | * @return an array containing all the <code>GraphicsDevice</code> | ||
| 224 | * objects that represent screen devices | ||
| 225 | * @exception HeadlessException if isHeadless() returns true | ||
| 226 | * @see #isHeadless() | ||
| 227 | */ | ||
| 228 | public abstract GraphicsDevice[] getScreenDevices() | ||
| 229 | throws HeadlessException; | ||
| 230 | |||
| 231 | /** | ||
| 232 | * Returns the default screen <code>GraphicsDevice</code>. | ||
| 233 | * @return the <code>GraphicsDevice</code> that represents the | ||
| 234 | * default screen device | ||
| 235 | * @exception HeadlessException if isHeadless() returns true | ||
| 236 | * @see #isHeadless() | ||
| 237 | */ | ||
| 238 | public abstract GraphicsDevice getDefaultScreenDevice() | ||
| 239 | throws HeadlessException; | ||
| 240 | |||
| 241 | /** | ||
| 242 | * Returns a <code>Graphics2D</code> object for rendering into the | ||
| 243 | * specified {@link BufferedImage}. | ||
| 244 | * @param img the specified <code>BufferedImage</code> | ||
| 245 | * @return a <code>Graphics2D</code> to be used for rendering into | ||
| 246 | * the specified <code>BufferedImage</code> | ||
| 247 | * @throws NullPointerException if <code>img</code> is null | ||
| 248 | */ | ||
| 249 | public abstract Graphics2D createGraphics(BufferedImage img); | ||
| 250 | |||
| 251 | /** | ||
| 252 | * Returns an array containing a one-point size instance of all fonts | ||
| 253 | * available in this <code>GraphicsEnvironment</code>. Typical usage | ||
| 254 | * would be to allow a user to select a particular font. Then, the | ||
| 255 | * application can size the font and set various font attributes by | ||
| 256 | * calling the <code>deriveFont</code> method on the choosen instance. | ||
| 257 | * <p> | ||
| 258 | * This method provides for the application the most precise control | ||
| 259 | * over which <code>Font</code> instance is used to render text. | ||
| 260 | * If a font in this <code>GraphicsEnvironment</code> has multiple | ||
| 261 | * programmable variations, only one | ||
| 262 | * instance of that <code>Font</code> is returned in the array, and | ||
| 263 | * other variations must be derived by the application. | ||
| 264 | * <p> | ||
| 265 | * If a font in this environment has multiple programmable variations, | ||
| 266 | * such as Multiple-Master fonts, only one instance of that font is | ||
| 267 | * returned in the <code>Font</code> array. The other variations | ||
| 268 | * must be derived by the application. | ||
| 269 | * | ||
| 270 | * @return an array of <code>Font</code> objects | ||
| 271 | * @see #getAvailableFontFamilyNames | ||
| 272 | * @see java.awt.Font | ||
| 273 | * @see java.awt.Font#deriveFont | ||
| 274 | * @see java.awt.Font#getFontName | ||
| 275 | * @since 1.2 | ||
| 276 | */ | ||
| 277 | public abstract Font[] getAllFonts(); | ||
| 278 | |||
| 279 | /** | ||
| 280 | * Returns an array containing the names of all font families in this | ||
| 281 | * <code>GraphicsEnvironment</code> localized for the default locale, | ||
| 282 | * as returned by <code>Locale.getDefault()</code>. | ||
| 283 | * <p> | ||
| 284 | * Typical usage would be for presentation to a user for selection of | ||
| 285 | * a particular family name. An application can then specify this name | ||
| 286 | * when creating a font, in conjunction with a style, such as bold or | ||
| 287 | * italic, giving the font system flexibility in choosing its own best | ||
| 288 | * match among multiple fonts in the same font family. | ||
| 289 | * | ||
| 290 | * @return an array of <code>String</code> containing font family names | ||
| 291 | * localized for the default locale, or a suitable alternative | ||
| 292 | * name if no name exists for this locale. | ||
| 293 | * @see #getAllFonts | ||
| 294 | * @see java.awt.Font | ||
| 295 | * @see java.awt.Font#getFamily | ||
| 296 | * @since 1.2 | ||
| 297 | */ | ||
| 298 | public abstract String[] getAvailableFontFamilyNames(); | ||
| 299 | |||
| 300 | /** | ||
| 301 | * Returns an array containing the names of all font families in this | ||
| 302 | * <code>GraphicsEnvironment</code> localized for the specified locale. | ||
| 303 | * <p> | ||
| 304 | * Typical usage would be for presentation to a user for selection of | ||
| 305 | * a particular family name. An application can then specify this name | ||
| 306 | * when creating a font, in conjunction with a style, such as bold or | ||
| 307 | * italic, giving the font system flexibility in choosing its own best | ||
| 308 | * match among multiple fonts in the same font family. | ||
| 309 | * | ||
| 310 | * @param l a {@link Locale} object that represents a | ||
| 311 | * particular geographical, political, or cultural region. | ||
| 312 | * Specifying <code>null</code> is equivalent to | ||
| 313 | * specifying <code>Locale.getDefault()</code>. | ||
| 314 | * @return an array of <code>String</code> containing font family names | ||
| 315 | * localized for the specified <code>Locale</code>, or a | ||
| 316 | * suitable alternative name if no name exists for the specified locale. | ||
| 317 | * @see #getAllFonts | ||
| 318 | * @see java.awt.Font | ||
| 319 | * @see java.awt.Font#getFamily | ||
| 320 | * @since 1.2 | ||
| 321 | */ | ||
| 322 | public abstract String[] getAvailableFontFamilyNames(Locale l); | ||
| 323 | |||
| 324 | /** | ||
| 325 | * Registers a <i>created</i> <code>Font</code>in this | ||
| 326 | * <code>GraphicsEnvironment</code>. | ||
| 327 | * A created font is one that was returned from calling | ||
| 328 | * {@link Font#createFont}, or derived from a created font by | ||
| 329 | * calling {@link Font#deriveFont}. | ||
| 330 | * After calling this method for such a font, it is available to | ||
| 331 | * be used in constructing new <code>Font</code>s by name or family name, | ||
| 332 | * and is enumerated by {@link #getAvailableFontFamilyNames} and | ||
| 333 | * {@link #getAllFonts} within the execution context of this | ||
| 334 | * application or applet. This means applets cannot register fonts in | ||
| 335 | * a way that they are visible to other applets. | ||
| 336 | * <p> | ||
| 337 | * Reasons that this method might not register the font and therefore | ||
| 338 | * return <code>false</code> are: | ||
| 339 | * <ul> | ||
| 340 | * <li>The font is not a <i>created</i> <code>Font</code>. | ||
| 341 | * <li>The font conflicts with a non-created <code>Font</code> already | ||
| 342 | * in this <code>GraphicsEnvironment</code>. For example if the name | ||
| 343 | * is that of a system font, or a logical font as described in the | ||
| 344 | * documentation of the {@link Font} class. It is implementation dependent | ||
| 345 | * whether a font may also conflict if it has the same family name | ||
| 346 | * as a system font. | ||
| 347 | * <p>Notice that an application can supersede the registration | ||
| 348 | * of an earlier created font with a new one. | ||
| 349 | * </ul> | ||
| 350 | * @return true if the <code>font</code> is successfully | ||
| 351 | * registered in this <code>GraphicsEnvironment</code>. | ||
| 352 | * @throws NullPointerException if <code>font</code> is null | ||
| 353 | * @since 1.6 | ||
| 354 | */ | ||
| 355 | public boolean registerFont(Font font) { | ||
| 356 | if (font == null) { | ||
| 357 | throw new NullPointerException("font cannot be null."); | ||
| 358 | } | ||
| 359 | FontManager fm = FontManagerFactory.getInstance(); | ||
| 360 | return fm.registerFont(font); | ||
| 361 | } | ||
| 362 | |||
| 363 | /** | ||
| 364 | * Indicates a preference for locale-specific fonts in the mapping of | ||
| 365 | * logical fonts to physical fonts. Calling this method indicates that font | ||
| 366 | * rendering should primarily use fonts specific to the primary writing | ||
| 367 | * system (the one indicated by the default encoding and the initial | ||
| 368 | * default locale). For example, if the primary writing system is | ||
| 369 | * Japanese, then characters should be rendered using a Japanese font | ||
| 370 | * if possible, and other fonts should only be used for characters for | ||
| 371 | * which the Japanese font doesn't have glyphs. | ||
| 372 | * <p> | ||
| 373 | * The actual change in font rendering behavior resulting from a call | ||
| 374 | * to this method is implementation dependent; it may have no effect at | ||
| 375 | * all, or the requested behavior may already match the default behavior. | ||
| 376 | * The behavior may differ between font rendering in lightweight | ||
| 377 | * and peered components. Since calling this method requests a | ||
| 378 | * different font, clients should expect different metrics, and may need | ||
| 379 | * to recalculate window sizes and layout. Therefore this method should | ||
| 380 | * be called before user interface initialisation. | ||
| 381 | * @since 1.5 | ||
| 382 | */ | ||
| 383 | public void preferLocaleFonts() { | ||
| 384 | FontManager fm = FontManagerFactory.getInstance(); | ||
| 385 | fm.preferLocaleFonts(); | ||
| 386 | } | ||
| 387 | |||
| 388 | /** | ||
| 389 | * Indicates a preference for proportional over non-proportional (e.g. | ||
| 390 | * dual-spaced CJK fonts) fonts in the mapping of logical fonts to | ||
| 391 | * physical fonts. If the default mapping contains fonts for which | ||
| 392 | * proportional and non-proportional variants exist, then calling | ||
| 393 | * this method indicates the mapping should use a proportional variant. | ||
| 394 | * <p> | ||
| 395 | * The actual change in font rendering behavior resulting from a call to | ||
| 396 | * this method is implementation dependent; it may have no effect at all. | ||
| 397 | * The behavior may differ between font rendering in lightweight and | ||
| 398 | * peered components. Since calling this method requests a | ||
| 399 | * different font, clients should expect different metrics, and may need | ||
| 400 | * to recalculate window sizes and layout. Therefore this method should | ||
| 401 | * be called before user interface initialisation. | ||
| 402 | * @since 1.5 | ||
| 403 | */ | ||
| 404 | public void preferProportionalFonts() { | ||
| 405 | FontManager fm = FontManagerFactory.getInstance(); | ||
| 406 | fm.preferProportionalFonts(); | ||
| 407 | } | ||
| 408 | |||
| 409 | /** | ||
| 410 | * Returns the Point where Windows should be centered. | ||
| 411 | * It is recommended that centered Windows be checked to ensure they fit | ||
| 412 | * within the available display area using getMaximumWindowBounds(). | ||
| 413 | * @return the point where Windows should be centered | ||
| 414 | * | ||
| 415 | * @exception HeadlessException if isHeadless() returns true | ||
| 416 | * @see #getMaximumWindowBounds | ||
| 417 | * @since 1.4 | ||
| 418 | */ | ||
| 419 | public Point getCenterPoint() throws HeadlessException { | ||
| 420 | // Default implementation: return the center of the usable bounds of the | ||
| 421 | // default screen device. | ||
| 422 | Rectangle usableBounds = | ||
| 423 | SunGraphicsEnvironment.getUsableBounds(getDefaultScreenDevice()); | ||
| 424 | return new Point((usableBounds.width / 2) + usableBounds.x, | ||
| 425 | (usableBounds.height / 2) + usableBounds.y); | ||
| 426 | } | ||
| 427 | |||
| 428 | /** | ||
| 429 | * Returns the maximum bounds for centered Windows. | ||
| 430 | * These bounds account for objects in the native windowing system such as | ||
| 431 | * task bars and menu bars. The returned bounds will reside on a single | ||
| 432 | * display with one exception: on multi-screen systems where Windows should | ||
| 433 | * be centered across all displays, this method returns the bounds of the | ||
| 434 | * entire display area. | ||
| 435 | * <p> | ||
| 436 | * To get the usable bounds of a single display, use | ||
| 437 | * <code>GraphicsConfiguration.getBounds()</code> and | ||
| 438 | * <code>Toolkit.getScreenInsets()</code>. | ||
| 439 | * @return the maximum bounds for centered Windows | ||
| 440 | * | ||
| 441 | * @exception HeadlessException if isHeadless() returns true | ||
| 442 | * @see #getCenterPoint | ||
| 443 | * @see GraphicsConfiguration#getBounds | ||
| 444 | * @see Toolkit#getScreenInsets | ||
| 445 | * @since 1.4 | ||
| 446 | */ | ||
| 447 | public Rectangle getMaximumWindowBounds() throws HeadlessException { | ||
| 448 | // Default implementation: return the usable bounds of the default screen | ||
| 449 | // device. This is correct for Microsoft Windows and non-Xinerama X11. | ||
| 450 | return SunGraphicsEnvironment.getUsableBounds(getDefaultScreenDevice()); | ||
| 451 | } | ||
| 452 | } | ||