| /* |
| * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| |
| package java.awt; |
| |
| import java.awt.image.BufferedImage; |
| import java.security.AccessController; |
| import java.util.Locale; |
| |
| import sun.font.FontManager; |
| import sun.font.FontManagerFactory; |
| import sun.java2d.HeadlessGraphicsEnvironment; |
| import sun.java2d.SunGraphicsEnvironment; |
| import sun.security.action.GetPropertyAction; |
| |
| /** |
| * |
| * The <code>GraphicsEnvironment</code> class describes the collection |
| * of {@link GraphicsDevice} objects and {@link java.awt.Font} objects |
| * available to a Java(tm) application on a particular platform. |
| * The resources in this <code>GraphicsEnvironment</code> might be local |
| * or on a remote machine. <code>GraphicsDevice</code> objects can be |
| * screens, printers or image buffers and are the destination of |
| * {@link Graphics2D} drawing methods. Each <code>GraphicsDevice</code> |
| * has a number of {@link GraphicsConfiguration} objects associated with |
| * it. These objects specify the different configurations in which the |
| * <code>GraphicsDevice</code> can be used. |
| * @see GraphicsDevice |
| * @see GraphicsConfiguration |
| */ |
| |
| public abstract class GraphicsEnvironment { |
| private static GraphicsEnvironment localEnv; |
| |
| /** |
| * The headless state of the Toolkit and GraphicsEnvironment |
| */ |
| private static Boolean headless; |
| |
| /** |
| * The headless state assumed by default |
| */ |
| private static Boolean defaultHeadless; |
| |
| /** |
| * This is an abstract class and cannot be instantiated directly. |
| * Instances must be obtained from a suitable factory or query method. |
| */ |
| protected GraphicsEnvironment() { |
| } |
| |
| /** |
| * Returns the local <code>GraphicsEnvironment</code>. |
| * @return the local <code>GraphicsEnvironment</code> |
| */ |
| public static synchronized GraphicsEnvironment getLocalGraphicsEnvironment() { |
| if (localEnv == null) { |
| localEnv = createGE(); |
| } |
| |
| return localEnv; |
| } |
| |
| /** |
| * Creates and returns the GraphicsEnvironment, according to the |
| * system property 'java.awt.graphicsenv'. |
| * |
| * @return the graphics environment |
| */ |
| private static GraphicsEnvironment createGE() { |
| GraphicsEnvironment ge; |
| String nm = AccessController.doPrivileged(new GetPropertyAction("java.awt.graphicsenv", null)); |
| try { |
| // long t0 = System.currentTimeMillis(); |
| Class geCls; |
| try { |
| // First we try if the bootclassloader finds the requested |
| // class. This way we can avoid to run in a privileged block. |
| geCls = Class.forName(nm); |
| } catch (ClassNotFoundException ex) { |
| // If the bootclassloader fails, we try again with the |
| // application classloader. |
| ClassLoader cl = ClassLoader.getSystemClassLoader(); |
| geCls = Class.forName(nm, true, cl); |
| } |
| ge = (GraphicsEnvironment) geCls.newInstance(); |
| // long t1 = System.currentTimeMillis(); |
| // System.out.println("GE creation took " + (t1-t0)+ "ms."); |
| if (isHeadless()) { |
| ge = new HeadlessGraphicsEnvironment(ge); |
| } |
| } catch (ClassNotFoundException e) { |
| throw new Error("Could not find class: "+nm); |
| } catch (InstantiationException e) { |
| throw new Error("Could not instantiate Graphics Environment: " |
| + nm); |
| } catch (IllegalAccessException e) { |
| throw new Error ("Could not access Graphics Environment: " |
| + nm); |
| } |
| return ge; |
| } |
| |
| /** |
| * Tests whether or not a display, keyboard, and mouse can be |
| * supported in this environment. If this method returns true, |
| * a HeadlessException is thrown from areas of the Toolkit |
| * and GraphicsEnvironment that are dependent on a display, |
| * keyboard, or mouse. |
| * @return <code>true</code> if this environment cannot support |
| * a display, keyboard, and mouse; <code>false</code> |
| * otherwise |
| * @see java.awt.HeadlessException |
| * @since 1.4 |
| */ |
| public static boolean isHeadless() { |
| return getHeadlessProperty(); |
| } |
| |
| /** |
| * @return warning message if headless state is assumed by default; |
| * null otherwise |
| * @since 1.5 |
| */ |
| static String getHeadlessMessage() { |
| if (headless == null) { |
| getHeadlessProperty(); // initialize the values |
| } |
| return defaultHeadless != Boolean.TRUE ? null : |
| "\nNo X11 DISPLAY variable was set, " + |
| "but this program performed an operation which requires it."; |
| } |
| |
| /** |
| * @return the value of the property "java.awt.headless" |
| * @since 1.4 |
| */ |
| private static boolean getHeadlessProperty() { |
| if (headless == null) { |
| java.security.AccessController.doPrivileged( |
| new java.security.PrivilegedAction() { |
| public Object run() { |
| String nm = System.getProperty("java.awt.headless"); |
| |
| if (nm == null) { |
| /* No need to ask for DISPLAY when run in a browser */ |
| if (System.getProperty("javaplugin.version") != null) { |
| headless = defaultHeadless = Boolean.FALSE; |
| } else { |
| String osName = System.getProperty("os.name"); |
| headless = defaultHeadless = |
| Boolean.valueOf(("Linux".equals(osName) || "SunOS".equals(osName)) && |
| (System.getenv("DISPLAY") == null)); |
| } |
| } else if (nm.equals("true")) { |
| headless = Boolean.TRUE; |
| } else { |
| headless = Boolean.FALSE; |
| } |
| return null; |
| } |
| } |
| ); |
| } |
| return headless.booleanValue(); |
| } |
| |
| /** |
| * Check for headless state and throw HeadlessException if headless |
| * @since 1.4 |
| */ |
| static void checkHeadless() throws HeadlessException { |
| if (isHeadless()) { |
| throw new HeadlessException(); |
| } |
| } |
| |
| /** |
| * Returns whether or not a display, keyboard, and mouse can be |
| * supported in this graphics environment. If this returns true, |
| * <code>HeadlessException</code> will be thrown from areas of the |
| * graphics environment that are dependent on a display, keyboard, or |
| * mouse. |
| * @return <code>true</code> if a display, keyboard, and mouse |
| * can be supported in this environment; <code>false</code> |
| * otherwise |
| * @see java.awt.HeadlessException |
| * @see #isHeadless |
| * @since 1.4 |
| */ |
| public boolean isHeadlessInstance() { |
| // By default (local graphics environment), simply check the |
| // headless property. |
| return getHeadlessProperty(); |
| } |
| |
| /** |
| * Returns an array of all of the screen <code>GraphicsDevice</code> |
| * objects. |
| * @return an array containing all the <code>GraphicsDevice</code> |
| * objects that represent screen devices |
| * @exception HeadlessException if isHeadless() returns true |
| * @see #isHeadless() |
| */ |
| public abstract GraphicsDevice[] getScreenDevices() |
| throws HeadlessException; |
| |
| /** |
| * Returns the default screen <code>GraphicsDevice</code>. |
| * @return the <code>GraphicsDevice</code> that represents the |
| * default screen device |
| * @exception HeadlessException if isHeadless() returns true |
| * @see #isHeadless() |
| */ |
| public abstract GraphicsDevice getDefaultScreenDevice() |
| throws HeadlessException; |
| |
| /** |
| * Returns a <code>Graphics2D</code> object for rendering into the |
| * specified {@link BufferedImage}. |
| * @param img the specified <code>BufferedImage</code> |
| * @return a <code>Graphics2D</code> to be used for rendering into |
| * the specified <code>BufferedImage</code> |
| * @throws NullPointerException if <code>img</code> is null |
| */ |
| public abstract Graphics2D createGraphics(BufferedImage img); |
| |
| /** |
| * Returns an array containing a one-point size instance of all fonts |
| * available in this <code>GraphicsEnvironment</code>. Typical usage |
| * would be to allow a user to select a particular font. Then, the |
| * application can size the font and set various font attributes by |
| * calling the <code>deriveFont</code> method on the choosen instance. |
| * <p> |
| * This method provides for the application the most precise control |
| * over which <code>Font</code> instance is used to render text. |
| * If a font in this <code>GraphicsEnvironment</code> has multiple |
| * programmable variations, only one |
| * instance of that <code>Font</code> is returned in the array, and |
| * other variations must be derived by the application. |
| * <p> |
| * If a font in this environment has multiple programmable variations, |
| * such as Multiple-Master fonts, only one instance of that font is |
| * returned in the <code>Font</code> array. The other variations |
| * must be derived by the application. |
| * |
| * @return an array of <code>Font</code> objects |
| * @see #getAvailableFontFamilyNames |
| * @see java.awt.Font |
| * @see java.awt.Font#deriveFont |
| * @see java.awt.Font#getFontName |
| * @since 1.2 |
| */ |
| public abstract Font[] getAllFonts(); |
| |
| /** |
| * Returns an array containing the names of all font families in this |
| * <code>GraphicsEnvironment</code> localized for the default locale, |
| * as returned by <code>Locale.getDefault()</code>. |
| * <p> |
| * Typical usage would be for presentation to a user for selection of |
| * a particular family name. An application can then specify this name |
| * when creating a font, in conjunction with a style, such as bold or |
| * italic, giving the font system flexibility in choosing its own best |
| * match among multiple fonts in the same font family. |
| * |
| * @return an array of <code>String</code> containing font family names |
| * localized for the default locale, or a suitable alternative |
| * name if no name exists for this locale. |
| * @see #getAllFonts |
| * @see java.awt.Font |
| * @see java.awt.Font#getFamily |
| * @since 1.2 |
| */ |
| public abstract String[] getAvailableFontFamilyNames(); |
| |
| /** |
| * Returns an array containing the names of all font families in this |
| * <code>GraphicsEnvironment</code> localized for the specified locale. |
| * <p> |
| * Typical usage would be for presentation to a user for selection of |
| * a particular family name. An application can then specify this name |
| * when creating a font, in conjunction with a style, such as bold or |
| * italic, giving the font system flexibility in choosing its own best |
| * match among multiple fonts in the same font family. |
| * |
| * @param l a {@link Locale} object that represents a |
| * particular geographical, political, or cultural region. |
| * Specifying <code>null</code> is equivalent to |
| * specifying <code>Locale.getDefault()</code>. |
| * @return an array of <code>String</code> containing font family names |
| * localized for the specified <code>Locale</code>, or a |
| * suitable alternative name if no name exists for the specified locale. |
| * @see #getAllFonts |
| * @see java.awt.Font |
| * @see java.awt.Font#getFamily |
| * @since 1.2 |
| */ |
| public abstract String[] getAvailableFontFamilyNames(Locale l); |
| |
| /** |
| * Registers a <i>created</i> <code>Font</code>in this |
| * <code>GraphicsEnvironment</code>. |
| * A created font is one that was returned from calling |
| * {@link Font#createFont}, or derived from a created font by |
| * calling {@link Font#deriveFont}. |
| * After calling this method for such a font, it is available to |
| * be used in constructing new <code>Font</code>s by name or family name, |
| * and is enumerated by {@link #getAvailableFontFamilyNames} and |
| * {@link #getAllFonts} within the execution context of this |
| * application or applet. This means applets cannot register fonts in |
| * a way that they are visible to other applets. |
| * <p> |
| * Reasons that this method might not register the font and therefore |
| * return <code>false</code> are: |
| * <ul> |
| * <li>The font is not a <i>created</i> <code>Font</code>. |
| * <li>The font conflicts with a non-created <code>Font</code> already |
| * in this <code>GraphicsEnvironment</code>. For example if the name |
| * is that of a system font, or a logical font as described in the |
| * documentation of the {@link Font} class. It is implementation dependent |
| * whether a font may also conflict if it has the same family name |
| * as a system font. |
| * <p>Notice that an application can supersede the registration |
| * of an earlier created font with a new one. |
| * </ul> |
| * @return true if the <code>font</code> is successfully |
| * registered in this <code>GraphicsEnvironment</code>. |
| * @throws NullPointerException if <code>font</code> is null |
| * @since 1.6 |
| */ |
| public boolean registerFont(Font font) { |
| if (font == null) { |
| throw new NullPointerException("font cannot be null."); |
| } |
| FontManager fm = FontManagerFactory.getInstance(); |
| return fm.registerFont(font); |
| } |
| |
| /** |
| * Indicates a preference for locale-specific fonts in the mapping of |
| * logical fonts to physical fonts. Calling this method indicates that font |
| * rendering should primarily use fonts specific to the primary writing |
| * system (the one indicated by the default encoding and the initial |
| * default locale). For example, if the primary writing system is |
| * Japanese, then characters should be rendered using a Japanese font |
| * if possible, and other fonts should only be used for characters for |
| * which the Japanese font doesn't have glyphs. |
| * <p> |
| * The actual change in font rendering behavior resulting from a call |
| * to this method is implementation dependent; it may have no effect at |
| * all, or the requested behavior may already match the default behavior. |
| * The behavior may differ between font rendering in lightweight |
| * and peered components. Since calling this method requests a |
| * different font, clients should expect different metrics, and may need |
| * to recalculate window sizes and layout. Therefore this method should |
| * be called before user interface initialisation. |
| * @since 1.5 |
| */ |
| public void preferLocaleFonts() { |
| FontManager fm = FontManagerFactory.getInstance(); |
| fm.preferLocaleFonts(); |
| } |
| |
| /** |
| * Indicates a preference for proportional over non-proportional (e.g. |
| * dual-spaced CJK fonts) fonts in the mapping of logical fonts to |
| * physical fonts. If the default mapping contains fonts for which |
| * proportional and non-proportional variants exist, then calling |
| * this method indicates the mapping should use a proportional variant. |
| * <p> |
| * The actual change in font rendering behavior resulting from a call to |
| * this method is implementation dependent; it may have no effect at all. |
| * The behavior may differ between font rendering in lightweight and |
| * peered components. Since calling this method requests a |
| * different font, clients should expect different metrics, and may need |
| * to recalculate window sizes and layout. Therefore this method should |
| * be called before user interface initialisation. |
| * @since 1.5 |
| */ |
| public void preferProportionalFonts() { |
| FontManager fm = FontManagerFactory.getInstance(); |
| fm.preferProportionalFonts(); |
| } |
| |
| /** |
| * Returns the Point where Windows should be centered. |
| * It is recommended that centered Windows be checked to ensure they fit |
| * within the available display area using getMaximumWindowBounds(). |
| * @return the point where Windows should be centered |
| * |
| * @exception HeadlessException if isHeadless() returns true |
| * @see #getMaximumWindowBounds |
| * @since 1.4 |
| */ |
| public Point getCenterPoint() throws HeadlessException { |
| // Default implementation: return the center of the usable bounds of the |
| // default screen device. |
| Rectangle usableBounds = |
| SunGraphicsEnvironment.getUsableBounds(getDefaultScreenDevice()); |
| return new Point((usableBounds.width / 2) + usableBounds.x, |
| (usableBounds.height / 2) + usableBounds.y); |
| } |
| |
| /** |
| * Returns the maximum bounds for centered Windows. |
| * These bounds account for objects in the native windowing system such as |
| * task bars and menu bars. The returned bounds will reside on a single |
| * display with one exception: on multi-screen systems where Windows should |
| * be centered across all displays, this method returns the bounds of the |
| * entire display area. |
| * <p> |
| * To get the usable bounds of a single display, use |
| * <code>GraphicsConfiguration.getBounds()</code> and |
| * <code>Toolkit.getScreenInsets()</code>. |
| * @return the maximum bounds for centered Windows |
| * |
| * @exception HeadlessException if isHeadless() returns true |
| * @see #getCenterPoint |
| * @see GraphicsConfiguration#getBounds |
| * @see Toolkit#getScreenInsets |
| * @since 1.4 |
| */ |
| public Rectangle getMaximumWindowBounds() throws HeadlessException { |
| // Default implementation: return the usable bounds of the default screen |
| // device. This is correct for Microsoft Windows and non-Xinerama X11. |
| return SunGraphicsEnvironment.getUsableBounds(getDefaultScreenDevice()); |
| } |
| } |
