replicant-frameworks_native/awt/java/awt/image/VolatileImage.java
2009-03-03 19:31:44 -08:00

147 lines
4.2 KiB
Java

/*
* 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 Alexey A. Petrenko
* @version $Revision$
*/
package java.awt.image;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsConfiguration;
import java.awt.Image;
import java.awt.ImageCapabilities;
import java.awt.Transparency;
/**
* The VolatileImage abstract class represents an image which can lose its
* contents at any point. VolatileImage objects are device specific. This class
* provides methods for checking if operation of this image are compatible for
* the GraphicsConfiguration.
*
* @since Android 1.0
*/
public abstract class VolatileImage extends Image
// Volatile image implements Transparency since 1.5
implements Transparency {
/**
* The Constant IMAGE_INCOMPATIBLE indicates that this VolatileImage is not
* applicable for the GraphicsConfiguration object.
*/
public static final int IMAGE_INCOMPATIBLE = 2;
/**
* The Constant IMAGE_OK indicates that VolatileImage is ready for using.
*/
public static final int IMAGE_OK = 0;
/**
* The Constant IMAGE_RESTORED indicates that VolatileImage will be ready to
* use after restoring.
*/
public static final int IMAGE_RESTORED = 1;
/**
* The transparency value of this image.
*/
protected int transparency = OPAQUE;
/**
* Instantiates a new VolatileImage object.
*/
public VolatileImage() {
super();
}
/**
* Returns true if rendering data is lost during validating. This method
* should be called after rendering operation of image.
*
* @return true, if contents lost during validating, false otherwise.
*/
public abstract boolean contentsLost();
/**
* Creates a Graphics2D used to draw in this VolatileImage.
*
* @return the Graphics2D object.
*/
public abstract Graphics2D createGraphics();
/**
* Gets the ImageCapabilities of this VolatileImage.
*
* @return the ImageCapabilities of this VolatileImage.
*/
public abstract ImageCapabilities getCapabilities();
/**
* Gets the height of this VolatileImage.
*
* @return the height of this VolatileImage.
*/
public abstract int getHeight();
/**
* Gets a BufferedImage representation of current VolatileImage that won't
* be affected by any changes to this VolatileImage.
*
* @return a BufferedImage representation of current VolatileImage.
*/
public abstract BufferedImage getSnapshot();
/**
* Gets the width of this VolatileImage.
*
* @return the width of this VolatileImage.
*/
public abstract int getWidth();
/**
* Validates the drawing surface of the image if the surface had been lost
* and if the specified GraphicsConfiguration object is applicable to this
* image.
*
* @param gc
* the GraphicsConfiguration object.
* @return one of the image status constants: IMAGE_OK, IMAGE_RESTORED or
* IMAGE_INCOMPATIBLE.
*/
public abstract int validate(GraphicsConfiguration gc);
@Override
public void flush() {
}
@Override
public Graphics getGraphics() {
return createGraphics();
}
@Override
public ImageProducer getSource() {
return getSnapshot().getSource();
}
public int getTransparency() {
return transparency;
}
}