查了一下JDT的实现
org.eclipse.jdt.ui.JavaElementImageDescriptor
public JavaElementImageDescriptor(ImageDescriptor baseImage, int flags, Point size);
使用于org.eclipse.jdt.ui.ProblemsLabelDecorator
public Image decorateImage(Image image, Object obj) {
int adornmentFlags= computeAdornmentFlags(obj);
if (adornmentFlags != 0) {
ImageDescriptor baseImage= new ImageImageDescriptor(image);
Rectangle bounds= image.getBounds();
return getRegistry().get(new JavaElementImageDescriptor(baseImage, adornmentFlags, new Point(bounds.width, bounds.height)));
}
return image;
}
JavaElementImageDescriptor.java
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/*******************************************************************************
* Copyright (c) 2000, 2004 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Common Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/cpl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.ui;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.Point;
import org.eclipse.jface.resource.CompositeImageDescriptor;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.util.Assert;
import org.eclipse.jdt.internal.ui.JavaPlugin;
import org.eclipse.jdt.internal.ui.JavaPluginImages;
/**
* A JavaImageDescriptor consists of a base image and several adornments. The adornments
* are computed according to the flags either passed during creation or set via the method
* <code>setAdornments</code>.
*
* <p>
* This class may be instantiated; it is not intended to be subclassed.
* </p>
*
* @since 2.0
*/
public class JavaElementImageDescriptor extends CompositeImageDescriptor {
/** Flag to render the abstract adornment. */
public final static int ABSTRACT= 0x001;
/** Flag to render the final adornment. */
public final static int FINAL= 0x002;
/** Flag to render the synchronized adornment. */
public final static int SYNCHRONIZED= 0x004;
/** Flag to render the static adornment. */
public final static int STATIC= 0x008;
/** Flag to render the runnable adornment. */
public final static int RUNNABLE= 0x010;
/** Flag to render the warning adornment. */
public final static int WARNING= 0x020;
/** Flag to render the error adornment. */
public final static int ERROR= 0x040;
/** Flag to render the 'override' adornment. */
public final static int OVERRIDES= 0x080;
/** Flag to render the 'implements' adornment. */
public final static int IMPLEMENTS= 0x100;
/** Flag to render the 'constructor' adornment. */
public final static int CONSTRUCTOR= 0x200;
/**
* Flag to render the 'deprecated' adornment.
* @since 3.0
*/
public final static int DEPRECATED= 0x400;
private ImageDescriptor fBaseImage;
private int fFlags;
private Point fSize;
/**
* Creates a new JavaElementImageDescriptor.
*
* @param baseImage an image descriptor used as the base image
* @param flags flags indicating which adornments are to be rendered. See <code>setAdornments</code>
* for valid values.
* @param size the size of the resulting image
* @see #setAdornments(int)
*/
public JavaElementImageDescriptor(ImageDescriptor baseImage, int flags, Point size) {
fBaseImage= baseImage;
Assert.isNotNull(fBaseImage);
fFlags= flags;
Assert.isTrue(fFlags >= 0);
fSize= size;
Assert.isNotNull(fSize);
}
/**
* Sets the descriptors adornments. Valid values are: <code>ABSTRACT</code>, <code>FINAL</code>,
* <code>SYNCHRONIZED</code>, </code>STATIC<code>, </code>RUNNABLE<code>, </code>WARNING<code>,
* </code>ERROR<code>, </code>OVERRIDDES<code>, <code>IMPLEMENTS</code>, <code>CONSTRUCTOR</code>,
* <code>DEPRECATED</code>, or any combination of those.
*
* @param adornments the image descriptors adornments
*/
public void setAdornments(int adornments) {
Assert.isTrue(adornments >= 0);
fFlags= adornments;
}
/**
* Returns the current adornments.
*
* @return the current adornments
*/
public int getAdronments() {
return fFlags;
}
/**
* Sets the size of the image created by calling <code>createImage()</code>.
*
* @param size the size of the image returned from calling <code>createImage()</code>
* @see ImageDescriptor#createImage()
*/
public void setImageSize(Point size) {
Assert.isNotNull(size);
Assert.isTrue(size.x >= 0 && size.y >= 0);
fSize= size;
}
/**
* Returns the size of the image created by calling <code>createImage()</code>.
*
* @return the size of the image created by calling <code>createImage()</code>
* @see ImageDescriptor#createImage()
*/
public Point getImageSize() {
return new Point(fSize.x, fSize.y);
}
/* (non-Javadoc)
* Method declared in CompositeImageDescriptor
*/
protected Point getSize() {
return fSize;
}
/* (non-Javadoc)
* Method declared on Object.
*/
public boolean equals(Object object) {
if (object == null || !JavaElementImageDescriptor.class.equals(object.getClass()))
return false;
JavaElementImageDescriptor other= (JavaElementImageDescriptor)object;
return (fBaseImage.equals(other.fBaseImage) && fFlags == other.fFlags && fSize.equals(other.fSize));
}
/* (non-Javadoc)
* Method declared on Object.
*/
public int hashCode() {
return fBaseImage.hashCode() | fFlags | fSize.hashCode();
}
/* (non-Javadoc)
* Method declared in CompositeImageDescriptor
*/
protected void drawCompositeImage(int width, int height) {
ImageData bg= getImageData(fBaseImage);
if ((fFlags & DEPRECATED) != 0) { // over the full image
Point size= getSize();
ImageData data= getImageData(JavaPluginImages.DESC_OVR_DEPRECATED);
drawImage(data, 0, size.y - data.height);
}
drawImage(bg, 0, 0);
drawTopRight();
drawBottomRight();
drawBottomLeft();
}
private ImageData getImageData(ImageDescriptor descriptor) {
ImageData data= descriptor.getImageData(); // see bug 51965: getImageData can return null
if (data == null) {
data= DEFAULT_IMAGE_DATA;
JavaPlugin.logErrorMessage("Image data not available: " + descriptor.toString()); //$NON-NLS-1$
}
return data;
}
private void drawTopRight() {
int x= getSize().x;
if ((fFlags & ABSTRACT) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_ABSTRACT);
x-= data.width;
drawImage(data, x, 0);
}
if ((fFlags & CONSTRUCTOR) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_CONSTRUCTOR);
x-= data.width;
drawImage(data, x, 0);
}
if ((fFlags & FINAL) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_FINAL);
x-= data.width;
drawImage(data, x, 0);
}
if ((fFlags & STATIC) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_STATIC);
x-= data.width;
drawImage(data, x, 0);
}
}
private void drawBottomRight() {
Point size= getSize();
int x= size.x;
int flags= fFlags;
int syncAndOver= SYNCHRONIZED | OVERRIDES;
int syncAndImpl= SYNCHRONIZED | IMPLEMENTS;
if ((flags & syncAndOver) == syncAndOver) { // both flags set: merged overlay image
ImageData data= getImageData(JavaPluginImages.DESC_OVR_SYNCH_AND_OVERRIDES);
x-= data.width;
drawImage(data, x, size.y - data.height);
flags &= ~syncAndOver; // clear to not render again
} else if ((flags & syncAndImpl) == syncAndImpl) { // both flags set: merged overlay image
ImageData data= getImageData(JavaPluginImages.DESC_OVR_SYNCH_AND_IMPLEMENTS);
x-= data.width;
drawImage(data, x, size.y - data.height);
flags &= ~syncAndImpl; // clear to not render again
}
if ((flags & OVERRIDES) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_OVERRIDES);
x-= data.width;
drawImage(data, x, size.y - data.height);
}
if ((flags & IMPLEMENTS) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_IMPLEMENTS);
x-= data.width;
drawImage(data, x, size.y - data.height);
}
if ((flags & SYNCHRONIZED) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_SYNCH);
x-= data.width;
drawImage(data, x, size.y - data.height);
}
if ((flags & RUNNABLE) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_RUN);
x-= data.width;
drawImage(data, x, size.y - data.height);
}
}
private void drawBottomLeft() {
Point size= getSize();
int x= 0;
if ((fFlags & ERROR) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_ERROR);
drawImage(data, x, size.y - data.height);
x+= data.width;
}
if ((fFlags & WARNING) != 0) {
ImageData data= getImageData(JavaPluginImages.DESC_OVR_WARNING);
drawImage(data, x, size.y - data.height);
x+= data.width;
}
}
}
===============
另外参考：
Taking a look at SWT Images http://www.eclipse.org/articles/Article-SWT-images/graphics-resources.html