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/******************************************************************************* * Copyright (c) 2001, 2006 IBM Corporation and others. * 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: * IBM Corporation - initial API and implementation * Jens Lukowski/Innoopract - initial renaming/restructuring * Angelo Zerr <angelo.zerr@gmail.com> - copied from org.eclipse.wst.xml.ui.internal.editor.XMLEditorPluginImageHelper * modified in order to process JSON Objects. *******************************************************************************/ package org.eclipse.wst.json.ui.internal.editor; import java.io.File; import java.net.MalformedURLException; import java.net.URL; import java.util.HashMap; import java.util.Map; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.jface.resource.ImageRegistry; import org.eclipse.json.schema.JSONSchemaType; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.ImageData; import org.eclipse.swt.graphics.ImageLoader; import org.eclipse.ui.plugin.AbstractUIPlugin; import org.eclipse.wst.json.core.document.IJSONNode; import org.eclipse.wst.json.ui.internal.JSONUIPlugin; import org.eclipse.wst.json.ui.internal.Logger; /** * Helper class to handle images provided by this plug-in. * * NOTE: For internal use only. For images used externally, please use the * Shared***ImageHelper class instead. * */ public class JSONEditorPluginImageHelper { private static JSONEditorPluginImageHelper instance = null; private static final String IMAGE_DIR = "wtp-json-images"; //$NON-NLS-1$ private final Map<ImageDescriptor, URL> fURLMap; private final File fTempDir; private int fImageCount; /** * Gets the instance. * * @return Returns a JSONEditorPluginImageHelper */ public synchronized static JSONEditorPluginImageHelper getInstance() { if (instance == null) { instance = new JSONEditorPluginImageHelper(); } return instance; } // save a descriptor for each image private Map<String, ImageDescriptor> fImageDescRegistry = null; private final String PLUGINID = JSONUIPlugin.PLUGIN_ID; public JSONEditorPluginImageHelper() { fURLMap = new HashMap<ImageDescriptor, URL>(); fTempDir = getTempDir(); fImageCount = 0; } /** * Creates an image from the given resource and adds the image to the image * registry. * * @param resource * @return Image */ private Image createImage(String resource) { ImageDescriptor desc = getImageDescriptor(resource); Image image = null; if (desc != null) { image = desc.createImage(); // dont add the missing image descriptor image to the image // registry if (!desc.equals(ImageDescriptor.getMissingImageDescriptor())) { getImageRegistry().put(resource, image); } } return image; } /** * Creates an image descriptor from the given imageFilePath and adds the * image descriptor to the image descriptor registry. If an image descriptor * could not be created, the default "missing" image descriptor is returned * but not added to the image descriptor registry. * * @param imageFilePath * @return ImageDescriptor image descriptor for imageFilePath or default * "missing" image descriptor if resource could not be found */ private ImageDescriptor createImageDescriptor(String imageFilePath) { ImageDescriptor imageDescriptor = AbstractUIPlugin.imageDescriptorFromPlugin(PLUGINID, imageFilePath); if (imageDescriptor != null) { getImageDescriptorRegistry().put(imageFilePath, imageDescriptor); } else { imageDescriptor = ImageDescriptor.getMissingImageDescriptor(); } return imageDescriptor; } public Image getImage(short nodeType) { String imageName = getImageName(nodeType); return imageName != null ? getImage(imageName) : null; } public ImageDescriptor getImageDescriptor(short nodeType) { String imageName = getImageName(nodeType); return imageName != null ? getImageDescriptor(imageName) : null; } private String getImageName(short nodeType) { switch (nodeType) { case IJSONNode.OBJECT_NODE: return JSONEditorPluginImages.IMG_OBJ_OBJECT; case IJSONNode.ARRAY_NODE: return JSONEditorPluginImages.IMG_OBJ_ARRAY; case IJSONNode.VALUE_BOOLEAN_NODE: return JSONEditorPluginImages.IMG_OBJ_VALUE_BOOLEAN; case IJSONNode.VALUE_NULL_NODE: return JSONEditorPluginImages.IMG_OBJ_VALUE_NULL; case IJSONNode.VALUE_NUMBER_NODE: return JSONEditorPluginImages.IMG_OBJ_VALUE_NUMBER; case IJSONNode.VALUE_STRING_NODE: return JSONEditorPluginImages.IMG_OBJ_VALUE_STRING; default: return null; } } public ImageDescriptor getImageDescriptor(JSONSchemaType type) { String imageName = getImageName(type); return imageName != null ? getImageDescriptor(imageName) : null; } public Image getImage(JSONSchemaType type) { String imageName = getImageName(type); return imageName != null ? getImage(imageName) : null; } private String getImageName(JSONSchemaType type) { if (type == null) { return null; } switch (type) { case Object: return JSONEditorPluginImages.IMG_OBJ_OBJECT; case Array: return JSONEditorPluginImages.IMG_OBJ_ARRAY; case Boolean: return JSONEditorPluginImages.IMG_OBJ_VALUE_BOOLEAN; case Null: return JSONEditorPluginImages.IMG_OBJ_VALUE_NULL; case Number: return JSONEditorPluginImages.IMG_OBJ_VALUE_NUMBER; case String: return JSONEditorPluginImages.IMG_OBJ_VALUE_STRING; default: return null; } } /** * Retrieves the image associated with resource from the image registry. If * the image cannot be retrieved, attempt to find and load the image at the * location specified in resource. * * @param resource * the image to retrieve * @return Image the image associated with resource or null if one could not * be found */ public Image getImage(String resource) { Image image = getImageRegistry().get(resource); if (image == null) { // create an image image = createImage(resource); } return image; } /** * Retrieves the image descriptor associated with resource from the image * descriptor registry. If the image descriptor cannot be retrieved, attempt * to find and load the image descriptor at the location specified in * resource. * * @param resource * the image descriptor to retrieve * @return ImageDescriptor the image descriptor assocated with resource or * the default "missing" image descriptor if one could not be found */ public ImageDescriptor getImageDescriptor(String resource) { ImageDescriptor imageDescriptor = getImageDescriptorRegistry().get(resource); if (imageDescriptor == null) { // create a descriptor imageDescriptor = createImageDescriptor(resource); } return imageDescriptor; } /** * Returns the image descriptor registry for this plugin. * * @return HashMap - image descriptor registry for this plugin */ private Map<String, ImageDescriptor> getImageDescriptorRegistry() { if (fImageDescRegistry == null) { fImageDescRegistry = new HashMap<String, ImageDescriptor>(); } return fImageDescRegistry; } /** * Returns the image registry for this plugin. * * @return ImageRegistry - image registry for this plugin */ private ImageRegistry getImageRegistry() { return JSONUIPlugin.getDefault().getImageRegistry(); } public URL getImageURL(ImageDescriptor descriptor) { if (fTempDir == null) return null; URL url = fURLMap.get(descriptor); if (url != null) return url; File imageFile = getNewFile(); ImageData imageData = descriptor.getImageData(); if (imageData == null) { return null; } ImageLoader loader = new ImageLoader(); loader.data = new ImageData[] { imageData }; loader.save(imageFile.getAbsolutePath(), SWT.IMAGE_PNG); try { url = imageFile.toURI().toURL(); fURLMap.put(descriptor, url); return url; } catch (MalformedURLException e) { Logger.logException("Failed to create image directory ", e); //$NON-NLS-1$ } return null; } private File getNewFile() { File file; do { file = new File(fTempDir, String.valueOf(getImageCount()) + ".png"); //$NON-NLS-1$ } while (file.exists()); return file; } private synchronized int getImageCount() { return fImageCount++; } private File getTempDir() { try { File imageDir = JSONUIPlugin.getDefault().getStateLocation().append(IMAGE_DIR).toFile(); if (imageDir.exists()) { // has not been deleted on previous shutdown delete(imageDir); } if (!imageDir.exists()) { imageDir.mkdir(); } if (!imageDir.isDirectory()) { Logger.log(Logger.ERROR, "Failed to create image directory " + imageDir.toString()); //$NON-NLS-1$ return null; } return imageDir; } catch (IllegalStateException e) { // no state location return null; } } private void delete(File file) { if (file.isDirectory()) { File[] listFiles = file.listFiles(); for (int i = 0; i < listFiles.length; i++) { delete(listFiles[i]); } } file.delete(); } }