/*******************************************************************************
* Copyright (c) 2012 Google, Inc.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Google, Inc. - initial API and implementation
*******************************************************************************/
package com.swtdesigner;
import java.io.File;
import java.io.InputStream;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.swt.graphics.*;
/**
* Utility class for managing OS resources associated with SWT/JFace controls such as
* colors, fonts, images, etc.
*
* !!! IMPORTANT !!! Application code must explicitly invoke the <code>dispose()</code>
* method to release the operating system resources managed by cached objects
* when those objects and OS resources are no longer needed (e.g. on
* application shutdown)
*
* This class may be freely distributed as part of any application or plugin.
*/
public class ResourceManager extends SWTResourceManager {
/**
* Dispose of cached objects and their underlying OS resources. This should
* only be called when the cached objects are no longer needed (e.g. on
* application shutdown)
*/
public static void dispose() {
disposeColors();
disposeFonts();
disposeImages();
disposeCursors();
}
//////////////////////////////
// Image support
//////////////////////////////
/**
* Maps image descriptors to images
*/
private static HashMap m_DescriptorImageMap = new HashMap();
/**
* Returns an image descriptor stored in the file at the specified path relative to the specified class
* @param clazz Class The class relative to which to find the image descriptor
* @param path String The path to the image file
* @return ImageDescriptor The image descriptor stored in the file at the specified path
*/
public static ImageDescriptor getImageDescriptor(Class clazz, String path) {
return ImageDescriptor.createFromFile(clazz, path);
}
/**
* Returns an image descriptor stored in the file at the specified path
* @param path String The path to the image file
* @return ImageDescriptor The image descriptor stored in the file at the specified path
*/
public static ImageDescriptor getImageDescriptor(String path) {
try {
return ImageDescriptor.createFromURL((new File(path)).toURL());
} catch (MalformedURLException e) {
return null;
}
}
/**
* Returns an image based on the specified image descriptor
* @param descriptor ImageDescriptor The image descriptor for the image
* @return Image The image based on the specified image descriptor
*/
public static Image getImage(ImageDescriptor descriptor) {
if (descriptor == null)
return null;
Image image = (Image) m_DescriptorImageMap.get(descriptor);
if (image == null) {
image = descriptor.createImage();
m_DescriptorImageMap.put(descriptor, image);
}
return image;
}
/**
* Dispose all of the cached images
*/
public static void disposeImages() {
SWTResourceManager.disposeImages();
// dispose ImageDescriptor images
{
for (Iterator I = m_DescriptorImageMap.values().iterator(); I.hasNext();) {
((Image) I.next()).dispose();
}
m_DescriptorImageMap.clear();
}
// dispose plugin images
{
for (Iterator I = m_URLImageMap.values().iterator(); I.hasNext();) {
((Image) I.next()).dispose();
}
m_URLImageMap.clear();
}
}
//////////////////////////////
// Plugin images support
//////////////////////////////
/**
* Maps URL to images
*/
private static HashMap m_URLImageMap = new HashMap();
/**
* Retuns an image based on a plugin and file path
* @param plugin Object The plugin containing the image
* @param name String The path to th eimage within the plugin
* @return Image The image stored in the file at the specified path
*/
public static Image getPluginImage(Object plugin, String name) {
try {
try {
URL url = getPluginImageURL(plugin, name);
if (m_URLImageMap.containsKey(url))
return (Image) m_URLImageMap.get(url);
InputStream is = url.openStream();
Image image;
try {
image = getImage(is);
m_URLImageMap.put(url, image);
} finally {
is.close();
}
return image;
} catch (Throwable e) {
// Ignore any exceptions
}
} catch (Throwable e) {
// Ignore any exceptions
}
return null;
}
/**
* Retuns an image descriptor based on a plugin and file path
* @param plugin Object The plugin containing the image
* @param name String The path to th eimage within the plugin
* @return ImageDescriptor The image descriptor stored in the file at the specified path
*/
public static ImageDescriptor getPluginImageDescriptor(Object plugin, String name) {
try {
try {
URL url = getPluginImageURL(plugin, name);
return ImageDescriptor.createFromURL(url);
} catch (Throwable e) {
// Ignore any exceptions
}
} catch (Throwable e) {
// Ignore any exceptions
}
return null;
}
/**
* Retuns an URL based on a plugin and file path
* @param plugin Object The plugin containing the file path
* @param name String The file path
* @return URL The URL representing the file at the specified path
* @throws Exception
*/
private static URL getPluginImageURL(Object plugin, String name) throws Exception {
// try to work with 'plugin' as with OSGI BundleContext
try {
Class bundleClass = Class.forName("org.osgi.framework.Bundle"); //$NON-NLS-1$
Class bundleContextClass = Class.forName("org.osgi.framework.BundleContext"); //$NON-NLS-1$
if (bundleContextClass.isAssignableFrom(plugin.getClass())) {
Method getBundleMethod = bundleContextClass.getMethod("getBundle", new Class[]{}); //$NON-NLS-1$
Object bundle = getBundleMethod.invoke(plugin, new Object[]{});
//
Class ipathClass = Class.forName("org.eclipse.core.runtime.IPath"); //$NON-NLS-1$
Class pathClass = Class.forName("org.eclipse.core.runtime.Path"); //$NON-NLS-1$
Constructor pathConstructor = pathClass.getConstructor(new Class[]{String.class});
Object path = pathConstructor.newInstance(new Object[]{name});
//
Class platformClass = Class.forName("org.eclipse.core.runtime.Platform"); //$NON-NLS-1$
Method findMethod = platformClass.getMethod("find", new Class[]{bundleClass, ipathClass}); //$NON-NLS-1$
return (URL) findMethod.invoke(null, new Object[]{bundle, path});
}
} catch (Throwable e) {
// Ignore any exceptions
}
// else work with 'plugin' as with usual Eclipse plugin
{
Class pluginClass = Class.forName("org.eclipse.core.runtime.Plugin"); //$NON-NLS-1$
if (pluginClass.isAssignableFrom(plugin.getClass())) {
//
Class ipathClass = Class.forName("org.eclipse.core.runtime.IPath"); //$NON-NLS-1$
Class pathClass = Class.forName("org.eclipse.core.runtime.Path"); //$NON-NLS-1$
Constructor pathConstructor = pathClass.getConstructor(new Class[]{String.class});
Object path = pathConstructor.newInstance(new Object[]{name});
//
Method findMethod = pluginClass.getMethod("find", new Class[]{ipathClass}); //$NON-NLS-1$
return (URL) findMethod.invoke(plugin, new Object[]{path});
}
}
return null;
}
}