/******************************************************************************* * Copyright (c) 2000, 2003 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.swt.examples.fileviewer;import org.eclipse.swt.*;import org.eclipse.swt.graphics.*;import org.eclipse.swt.program.*;import org.eclipse.swt.widgets.*;import java.io.*;import java.util.*;/** * Manages icons for the application. * This is necessary as we could easily end up creating thousands of icons * bearing the same image. */class IconCache {	// Stock images	public final int		shellIcon = 0,		iconClosedDrive = 1,		iconClosedFolder = 2,		iconFile = 3,		iconOpenDrive = 4,		iconOpenFolder = 5,		cmdCopy = 6,		cmdCut = 7,		cmdDelete = 8,		cmdParent = 9,		cmdPaste = 10,		cmdPrint = 11,		cmdRefresh = 12,		cmdRename = 13,		cmdSearch = 14;	public final String[] stockImageLocations = {		"generic_example.gif",		"icon_ClosedDrive.gif",		"icon_ClosedFolder.gif",		"icon_File.gif",		"icon_OpenDrive.gif",		"icon_OpenFolder.gif",		"cmd_Copy.gif",		"cmd_Cut.gif",		"cmd_Delete.gif",		"cmd_Parent.gif",		"cmd_Paste.gif",		"cmd_Print.gif",		"cmd_Refresh.gif",		"cmd_Rename.gif",		"cmd_Search.gif"	};	public Image stockImages[];		// Stock cursors	public final int		cursorDefault = 0,		cursorWait = 1;	public Cursor stockCursors[];	// Cached icons	private Hashtable iconCache; /* map Program to Image */		public IconCache() {	}	/**	 * Loads the resources	 * 	 * @param display the display	 */	public void initResources(Display display) {		if (stockImages == null) {			stockImages = new Image[stockImageLocations.length];							for (int i = 0; i < stockImageLocations.length; ++i) {				Image image = createStockImage(display, stockImageLocations[i]);				if (image == null) {					freeResources();					throw new IllegalStateException(						FileViewer.getResourceString("error.CouldNotLoadResources"));				}				stockImages[i] = image;			}		}			if (stockCursors == null) {			stockCursors = new Cursor[] {				null,				new Cursor(display, SWT.CURSOR_WAIT)			};		}		iconCache = new Hashtable();	}	/**	 * Frees the resources	 */	public void freeResources() {		if (stockImages != null) {			for (int i = 0; i < stockImages.length; ++i) {				final Image image = stockImages[i];				if (image != null) image.dispose();			}			stockImages = null;		}		if (iconCache != null) {			for (Enumeration it = iconCache.elements(); it.hasMoreElements(); ) {				Image image = (Image) it.nextElement();				image.dispose();			}		}	}	/**	 * Creates a stock image	 * 	 * @param display the display	 * @param path the relative path to the icon	 */	private Image createStockImage(Display display, String path) {		try {			InputStream stream = IconCache.class.getResourceAsStream(path);			if (stream != null) {				ImageData imageData = new ImageData(stream);				if (imageData != null) {					ImageData mask = imageData.getTransparencyMask();					return new Image(display, imageData, mask);				}			}		} catch (Exception e) {		}		return null;	}	/**	 * Gets an image for a file associated with a given program	 *	 * @param program the Program	 */	public Image getIconFromProgram(Program program) {		Image image = (Image) iconCache.get(program);		if (image == null) {			ImageData imageData = program.getImageData();			if (imageData != null) {				image = new Image(null, imageData, imageData.getTransparencyMask());				iconCache.put(program, image);			} else {				image = stockImages[iconFile];			}		}		return image;	}}