Java tutorial
/******************************************************************************* * Copyright (c) 2011 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 br.com.santos.celeste.outros; 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 java.util.Map; import org.eclipse.core.runtime.Platform; import org.eclipse.jface.resource.CompositeImageDescriptor; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.Rectangle; import org.osgi.framework.Bundle; /** * 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. * <p> * * @author scheglov_ke * @author Dan Rubel */ public class ResourceManager extends SWTResourceManager { //////////////////////////////////////////////////////////////////////////// // // Image // //////////////////////////////////////////////////////////////////////////// private static Map<ImageDescriptor, Image> m_descriptorImageMap = new HashMap<ImageDescriptor, Image>(); /** * Returns an {@link ImageDescriptor} stored in the file at the specified path relative to the specified * class. * * @param clazz * the {@link Class} relative to which to find the image descriptor. * @param path * the path to the image file. * @return the {@link ImageDescriptor} stored in the file at the specified path. */ public static ImageDescriptor getImageDescriptor(Class<?> clazz, String path) { return ImageDescriptor.createFromFile(clazz, path); } /** * Returns an {@link ImageDescriptor} stored in the file at the specified path. * * @param path * the path to the image file. * @return the {@link ImageDescriptor} stored in the file at the specified path. */ public static ImageDescriptor getImageDescriptor(String path) { try { return ImageDescriptor.createFromURL(new File(path).toURI().toURL()); } catch (MalformedURLException e) { return null; } } /** * Returns an {@link Image} based on the specified {@link ImageDescriptor}. * * @param descriptor * the {@link ImageDescriptor} for the {@link Image}. * @return the {@link Image} based on the specified {@link ImageDescriptor}. */ public static Image getImage(ImageDescriptor descriptor) { if (descriptor == null) { return null; } Image image = m_descriptorImageMap.get(descriptor); if (image == null) { image = descriptor.createImage(); m_descriptorImageMap.put(descriptor, image); } return image; } /** * Maps images to decorated images. */ @SuppressWarnings("unchecked") private static Map<Image, Map<Image, Image>>[] m_decoratedImageMap = new Map[LAST_CORNER_KEY]; /** * Returns an {@link Image} composed of a base image decorated by another image. * * @param baseImage * the base {@link Image} that should be decorated. * @param decorator * the {@link Image} to decorate the base image. * @return {@link Image} The resulting decorated image. */ public static Image decorateImage(Image baseImage, Image decorator) { return decorateImage(baseImage, decorator, BOTTOM_RIGHT); } /** * Returns an {@link Image} composed of a base image decorated by another image. * * @param baseImage * the base {@link Image} that should be decorated. * @param decorator * the {@link Image} to decorate the base image. * @param corner * the corner to place decorator image. * @return the resulting decorated {@link Image}. */ public static Image decorateImage(final Image baseImage, final Image decorator, final int corner) { if (corner <= 0 || corner >= LAST_CORNER_KEY) { throw new IllegalArgumentException("Wrong decorate corner"); } Map<Image, Map<Image, Image>> cornerDecoratedImageMap = m_decoratedImageMap[corner]; if (cornerDecoratedImageMap == null) { cornerDecoratedImageMap = new HashMap<Image, Map<Image, Image>>(); m_decoratedImageMap[corner] = cornerDecoratedImageMap; } Map<Image, Image> decoratedMap = cornerDecoratedImageMap.get(baseImage); if (decoratedMap == null) { decoratedMap = new HashMap<Image, Image>(); cornerDecoratedImageMap.put(baseImage, decoratedMap); } // Image result = decoratedMap.get(decorator); if (result == null) { final Rectangle bib = baseImage.getBounds(); final Rectangle dib = decorator.getBounds(); final Point baseImageSize = new Point(bib.width, bib.height); CompositeImageDescriptor compositImageDesc = new CompositeImageDescriptor() { @Override protected void drawCompositeImage(int width, int height) { drawImage(baseImage.getImageData(), 0, 0); if (corner == TOP_LEFT) { drawImage(decorator.getImageData(), 0, 0); } else if (corner == TOP_RIGHT) { drawImage(decorator.getImageData(), bib.width - dib.width, 0); } else if (corner == BOTTOM_LEFT) { drawImage(decorator.getImageData(), 0, bib.height - dib.height); } else if (corner == BOTTOM_RIGHT) { drawImage(decorator.getImageData(), bib.width - dib.width, bib.height - dib.height); } } @Override protected Point getSize() { return baseImageSize; } }; // result = compositImageDesc.createImage(); decoratedMap.put(decorator, result); } return result; } /** * Dispose all of the cached images. */ public static void disposeImages() { SWTResourceManager.disposeImages(); // dispose ImageDescriptor images { for (Iterator<Image> I = m_descriptorImageMap.values().iterator(); I.hasNext();) { I.next().dispose(); } m_descriptorImageMap.clear(); } // dispose decorated images for (int i = 0; i < m_decoratedImageMap.length; i++) { Map<Image, Map<Image, Image>> cornerDecoratedImageMap = m_decoratedImageMap[i]; if (cornerDecoratedImageMap != null) { for (Map<Image, Image> decoratedMap : cornerDecoratedImageMap.values()) { for (Image image : decoratedMap.values()) { image.dispose(); } decoratedMap.clear(); } cornerDecoratedImageMap.clear(); } } // dispose plugin images { for (Iterator<Image> I = m_URLImageMap.values().iterator(); I.hasNext();) { I.next().dispose(); } m_URLImageMap.clear(); } } //////////////////////////////////////////////////////////////////////////// // // Plugin images support // //////////////////////////////////////////////////////////////////////////// /** * Maps URL to images. */ private static Map<String, Image> m_URLImageMap = new HashMap<String, Image>(); /** * Provider for plugin resources, used by WindowBuilder at design time. */ public interface PluginResourceProvider { URL getEntry(String symbolicName, String path); } /** * Instance of {@link PluginResourceProvider}, used by WindowBuilder at design time. */ private static PluginResourceProvider m_designTimePluginResourceProvider = null; /** * Returns an {@link Image} based on a plugin and file path. * * @param plugin * the plugin {@link Object} containing the image * @param name * the path to the image within the plugin * @return the {@link Image} stored in the file at the specified path * * @deprecated Use {@link #getPluginImage(String, String)} instead. */ @Deprecated public static Image getPluginImage(Object plugin, String name) { try { URL url = getPluginImageURL(plugin, name); if (url != null) { return getPluginImageFromUrl(url); } } catch (Throwable e) { // Ignore any exceptions } return null; } /** * Returns an {@link Image} based on a {@link Bundle} and resource entry path. * * @param symbolicName * the symbolic name of the {@link Bundle}. * @param path * the path of the resource entry. * @return the {@link Image} stored in the file at the specified path. */ public static Image getPluginImage(String symbolicName, String path) { try { URL url = getPluginImageURL(symbolicName, path); if (url != null) { return getPluginImageFromUrl(url); } } catch (Throwable e) { // Ignore any exceptions } return null; } /** * Returns an {@link Image} based on given {@link URL}. */ private static Image getPluginImageFromUrl(URL url) { try { try { String key = url.toExternalForm(); Image image = m_URLImageMap.get(key); if (image == null) { InputStream stream = url.openStream(); try { image = getImage(stream); m_URLImageMap.put(key, image); } finally { stream.close(); } } return image; } catch (Throwable e) { // Ignore any exceptions } } catch (Throwable e) { // Ignore any exceptions } return null; } /** * Returns an {@link ImageDescriptor} based on a plugin and file path. * * @param plugin * the plugin {@link Object} containing the image. * @param name * the path to th eimage within the plugin. * @return the {@link ImageDescriptor} stored in the file at the specified path. * * @deprecated Use {@link #getPluginImageDescriptor(String, String)} instead. */ @Deprecated 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; } /** * Returns an {@link ImageDescriptor} based on a {@link Bundle} and resource entry path. * * @param symbolicName * the symbolic name of the {@link Bundle}. * @param path * the path of the resource entry. * @return the {@link ImageDescriptor} based on a {@link Bundle} and resource entry path. */ public static ImageDescriptor getPluginImageDescriptor(String symbolicName, String path) { try { URL url = getPluginImageURL(symbolicName, path); if (url != null) { return ImageDescriptor.createFromURL(url); } } catch (Throwable e) { // Ignore any exceptions } return null; } /** * Returns an {@link URL} based on a {@link Bundle} and resource entry path. */ private static URL getPluginImageURL(String symbolicName, String path) { // try runtime plugins { Bundle bundle = Platform.getBundle(symbolicName); if (bundle != null) { return bundle.getEntry(path); } } // try design time provider if (m_designTimePluginResourceProvider != null) { return m_designTimePluginResourceProvider.getEntry(symbolicName, path); } // no such resource return null; } /** * Returns an {@link URL} based on a plugin and file path. * * @param plugin * the plugin {@link Object} containing the file path. * @param name * the file path. * @return the {@link 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[0]); //$NON-NLS-1$ Object bundle = getBundleMethod.invoke(plugin, new Object[0]); // 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<?> IPathClass = Class.forName("org.eclipse.core.runtime.IPath"); //$NON-NLS-1$ 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<?> 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<?> IPathClass = Class.forName("org.eclipse.core.runtime.IPath"); //$NON-NLS-1$ Method findMethod = PluginClass.getMethod("find", new Class[] { IPathClass }); //$NON-NLS-1$ return (URL) findMethod.invoke(plugin, new Object[] { path }); } } return null; } //////////////////////////////////////////////////////////////////////////// // // General // //////////////////////////////////////////////////////////////////////////// /** * 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(); } }