diff options
Diffstat (limited to 'libjava/java/awt/GraphicsEnvironment.java')
| -rw-r--r-- | libjava/java/awt/GraphicsEnvironment.java | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/libjava/java/awt/GraphicsEnvironment.java b/libjava/java/awt/GraphicsEnvironment.java new file mode 100644 index 00000000000..63e23e2f108 --- /dev/null +++ b/libjava/java/awt/GraphicsEnvironment.java @@ -0,0 +1,210 @@ +/* GraphicsEnvironment.java -- information about the graphics environment + Copyright (C) 2002 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath 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 for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA +02111-1307 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package java.awt; + +import java.awt.image.BufferedImage; +import java.util.Locale; + +/** + * This descibes the collection of GraphicsDevice and Font objects available + * on a given platform. The resources might be local or remote, and specify + * the valid configurations for displaying graphics. + * + * @author Eric Blake <ebb9@email.byu.edu> + * @see GraphicsDevice + * @see GraphicsConfiguration + * @since 1.4 + * @status updated to 1.4 + */ +public abstract class GraphicsEnvironment +{ + /** + * The environment must be obtained from a factory or query method, hence + * this constructor is protected. + */ + protected GraphicsEnvironment() + { + } + + /** + * Returns the local graphics environment. + * + * XXX Not implemented in Classpath yet. + * @return the local environment + */ + public static GraphicsEnvironment getLocalGraphicsEnvironment() + { + throw new Error("not implemented"); + } + + /** + * Check if the local environment is headless, meaning that it does not + * support a display, keyboard, or mouse. Many methods in the Abstract + * Windows Toolkit (java.awt) throw a {@link HeadlessException} if this + * returns true. + * + * XXX For now, Classpath assumes that it is never headless. + * + * @return true if the environment is headless, meaning that graphics are + * unsupported + * @since 1.4 + */ + public static boolean isHeadless() + { + // XXX Should be: getLocalGraphicsEnvironment().isHeadlessInstance(); + return false; + } + + /** + * Check if the given environment is headless, meaning that it does not + * support a display, keyboard, or mouse. Many methods in the Abstract + * Windows Toolkit (java.awt) throw a {@link HeadlessException} if this + * returns true. This default implementation returns false, so subclasses + * need only override it if they are headless. + * + * @return true if the environment is headless, meaning that graphics are + * unsupported + * @since 1.4 + */ + public boolean isHeadlessInstance() + { + return false; + } + + /** + * Get an array of all the GraphicsDevice objects. + * + * @return the available graphics devices, may be 0 length + * @throws HeadlessException if the environment is headless + */ + public abstract GraphicsDevice[] getScreenDevices(); + + /** + * Get the default screen GraphicsDevice object. + * + * @return the default screen device + * @throws HeadlessException if the environment is headless + */ + public abstract GraphicsDevice getDefaultScreenDevice(); + + /** + * Return a Graphics2D object which will render into the specified image. + * + * @param image the image to render into + * @return the object that renders into the image + */ + public abstract Graphics2D createGraphics(BufferedImage image); + + /** + * Returns an array of the one-point size fonts available in this + * environment. From there, the user can select the font and derive the + * correct one of proper size and attributes, using <code>deriveFont</code>. + * Only one master version of each font appears in this array; if a font + * can be derived from another, it must be created in that way. + * + * @return the array of available fonts + * @see #getAvailableFontFamilyNames() + * @see Font#deriveFont(int, float) + * @since 1.2 + */ + public abstract Font[] getAllFonts(); + + /** + * Returns an array of the font family names available in this environment. + * This allows flexibility in choosing the style of font, while still letting + * the Font class decide its best match. + * + * @return the array of available font families + * @see #getAllFonts() + * @see Font#getFamily() + * @since 1.2 + */ + public abstract String[] getAvailableFontFamilyNames(); + + /** + * Returns an array of the font family names available in this environment, + * localized to the current Locale if l is non-null. This allows + * flexibility in choosing the style of font, while still letting the Font + * class decide its best match. + * + * @param l the locale to use + * @return the array of available font families, localized + * @see #getAllFonts() + * @see Font#getFamily() + * @since 1.2 + */ + public abstract String[] getAvailableFontFamilyNames(Locale l); + + /** + * Returns the point where a window should be centered. You should probably + * also check that the window fits within the screen bounds. The default + * simply returns the center of the maximum window bounds; subclasses should + * override this if native objects (like scrollbars) make that off-centered. + * + * @return the centering point + * @throws HeadlessException if the environment is headless + * @see #getMaximumWindowBounds() + * @since 1.4 + */ + public Point getCenterPoint() + { + Rectangle r = getMaximumWindowBounds(); + return new Point(r.x + r.width / 2, r.y + r.height / 2); + } + + /** + * Returns the maximum bounds for a centered window object. The default + * implementation simply returns the bounds of the default configuration + * of the default screen; subclasses should override this to if native + * objects (like scrollbars) reduce what is truly available. Also, + * subclasses should override this if the window should be centered across + * a multi-screen display. + * + * @return the maximum window bounds + * @throws HeadlessException if the environment is headless + * @see #getCenterPoint() + * @see GraphicsConfiguration#getBounds() + * @see Toolkit#getScreenInsets(GraphicsConfiguration) + * @since 1.4 + */ + public Rectangle getMaximumWindowBounds() + { + return getDefaultScreenDevice().getDefaultConfiguration().getBounds(); + } +} // class GraphicsEnvironment |