/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @author Oleg V. Khaschansky
* @version $Revision$
*/
package java.awt;
import java.awt.image.BufferedImage;
import java.util.Locale;
import org.apache.harmony.awt.ContextStorage;
import org.apache.harmony.awt.gl.CommonGraphics2DFactory;
/**
* The GraphicsEnvironment class defines a collection of GraphicsDevice objects
* and Font objects which are available for Java application on current
* platform.
*
* @since Android 1.0
*/
public abstract class GraphicsEnvironment {
/**
* Constructor could not be used directly and should be obtained in extended
* classes.
*/
protected GraphicsEnvironment() {
}
/**
* Gets the local GraphicsEnvironment.
*
* @return the local GraphicsEnvironment.
*/
public static GraphicsEnvironment getLocalGraphicsEnvironment() {
synchronized (ContextStorage.getContextLock()) {
if (ContextStorage.getGraphicsEnvironment() == null) {
if (isHeadless()) {
ContextStorage.setGraphicsEnvironment(new HeadlessGraphicsEnvironment());
} else {
CommonGraphics2DFactory g2df = (CommonGraphics2DFactory)Toolkit
.getDefaultToolkit().getGraphicsFactory();
ContextStorage.setGraphicsEnvironment(g2df
.createGraphicsEnvironment(ContextStorage.getWindowFactory()));
}
}
return ContextStorage.getGraphicsEnvironment();
}
}
/**
* Returns whether or not a display, keyboard, and mouse are supported in
* this graphics environment.
*
* @return true, if HeadlessException will be thrown from areas of the
* graphics environment that are dependent on a display, keyboard,
* or mouse, false otherwise.
*/
public boolean isHeadlessInstance() {
return false;
}
/**
* Checks whether or not a display, keyboard, and mouse are supported in
* this environment.
*
* @return true, if a HeadlessException is thrown from areas of the Toolkit
* and GraphicsEnvironment that are dependent on a display,
* keyboard, or mouse, false otherwise.
*/
public static boolean isHeadless() {
return "true".equals(System.getProperty("java.awt.headless"));
}
/**
* Gets the maximum bounds of system centered windows.
*
* @return the maximum bounds of system centered windows.
* @throws HeadlessException
* if isHeadless() method returns true.
*/
public Rectangle getMaximumWindowBounds() throws HeadlessException {
return getDefaultScreenDevice().getDefaultConfiguration().getBounds();
}
/**
* Gets the Point which should defines the center of system window.
*
* @return the Point where the system window should be centered.
* @throws HeadlessException
* if isHeadless() method returns true.
*/
public Point getCenterPoint() throws HeadlessException {
Rectangle mwb = getMaximumWindowBounds();
return new Point(mwb.width >> 1, mwb.height >> 1);
}
/**
* Indicates that the primary font should be used. Primary font is specified
* by initial system locale or default encoding).
*/
public void preferLocaleFonts() {
// Note: API specification says following:
// "The actual change in font rendering behavior resulting
// from a call to this method is implementation dependent;
// it may have no effect at all." So, doing nothing is an
// acceptable behavior for this method.
// For now FontManager uses 1.4 font.properties scheme for font mapping,
// so
// this method doesn't make any sense. The implementation of this method
// which will influence font mapping is postponed until
// 1.5 mapping scheme not implemented.
// todo - Implement non-default behavior with 1.5 font mapping scheme
}
/**
* Indicates that a proportional preference of the font should be used.
*/
public void preferProportionalFonts() {
// Note: API specification says following:
// "The actual change in font rendering behavior resulting
// from a call to this method is implementation dependent;
// it may have no effect at all." So, doing nothing is an
// acceptable behavior for this method.
// For now FontManager uses 1.4 font.properties scheme for font mapping,
// so
// this method doesn't make any sense. The implementation of this method
// which will influence font mapping is postponed until
// 1.5 mapping scheme not implemented.
// todo - Implement non-default behavior with 1.5 font mapping scheme
}
/**
* Creates the Graphics2D object for rendering to the specified
* BufferedImage.
*
* @param bufferedImage
* the BufferedImage object.
* @return the Graphics2D object which allows to render to the specified
* BufferedImage.
*/
public abstract Graphics2D createGraphics(BufferedImage bufferedImage);
/**
* Gets the array of all available fonts instances in this
* GraphicsEnviroments.
*
* @return the array of all available fonts instances in this
* GraphicsEnviroments.
*/
public abstract Font[] getAllFonts();
/**
* Gets the array of all available font family names.
*
* @return the array of all available font family names.
*/
public abstract String[] getAvailableFontFamilyNames();
/**
* Gets the array of all available font family names for the specified
* locale.
*
* @param locale
* the Locale object which represents geographical region. The
* default locale is used if locale is null.
* @return the array of available font family names for the specified
* locale.
*/
public abstract String[] getAvailableFontFamilyNames(Locale locale);
/**
* Gets the default screen device as GraphicDevice object.
*
* @return the GraphicDevice object which represents default screen device.
* @throws HeadlessException
* if isHeadless() returns true.
*/
public abstract GraphicsDevice getDefaultScreenDevice() throws HeadlessException;
/**
* Gets an array of all available screen devices.
*
* @return the array of GraphicsDevice objects which represents all
* available screen devices.
* @throws HeadlessException
* if isHeadless() returns true.
*/
public abstract GraphicsDevice[] getScreenDevices() throws HeadlessException;
}
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