org.emftext.sdk.concretesyntax.resource.cs.ui.CsImageProvider.java Source code

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Here is the source code for org.emftext.sdk.concretesyntax.resource.cs.ui.CsImageProvider.java

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/*******************************************************************************
 * Copyright (c) 2006-2015
 * Software Technology Group, Dresden University of Technology
 * DevBoost GmbH, Dresden, Amtsgericht Dresden, HRB 34001
 *
 * 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:
 *   Software Technology Group - TU Dresden, Germany;
 *   DevBoost GmbH - Dresden, Germany
 *      - initial API and implementation
 ******************************************************************************/

package org.emftext.sdk.concretesyntax.resource.cs.ui;

import java.lang.reflect.Field;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.LinkedHashMap;
import java.util.Map;
import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.ISharedImages;
import org.eclipse.ui.PlatformUI;

/**
 * A provider class for all images that are required by the generated UI plug-in.
 * The default implementation load images from the bundle and caches them to make
 * sure each image is loaded at most once.
 */
public class CsImageProvider {

    public final static CsImageProvider INSTANCE = new CsImageProvider();

    private Map<String, Image> imageCache = new LinkedHashMap<String, Image>();

    /**
     * Returns the image associated with the given key. The key can be either a path
     * to an image file in the resource bundle or a shared image from
     * org.eclipse.ui.ISharedImages.
     */
    public Image getImage(String key) {
        if (key == null) {
            return null;
        }
        Image image = null;
        // try shared images
        try {
            Field declaredField = ISharedImages.class.getDeclaredField(key);
            Object valueObject = declaredField.get(null);
            if (valueObject instanceof String) {
                String value = (String) valueObject;
                image = PlatformUI.getWorkbench().getSharedImages().getImage(value);
            }
        } catch (SecurityException e) {
        } catch (NoSuchFieldException e) {
        } catch (IllegalArgumentException e) {
        } catch (IllegalAccessException e) {
        }
        if (image != null) {
            return image;
        }

        // try cache
        if (imageCache.containsKey(key)) {
            return imageCache.get(key);
        }

        // try loading image from UI bundle
        ImageDescriptor descriptor = getImageDescriptor(key);
        if (descriptor == null) {
            return null;
        }
        image = descriptor.createImage();
        if (image == null) {
            return null;
        }
        imageCache.put(key, image);
        return image;
    }

    /**
     * <p>
     * Returns the image for the given key. Possible keys are:
     * </p>
     * <p>
     * <ul>
     * </p>
     * <p>
     * <li>platform:/plugin/your.plugin/icons/yourIcon.png</li>
     * </p>
     * <p>
     * <li>bundleentry://557.fwk3560063/icons/yourIcon.png</li>
     * </p>
     * <p>
     * </ul>
     * </p>
     */
    public ImageDescriptor getImageDescriptor(String key) {
        IPath path = new Path(key);
        org.emftext.sdk.concretesyntax.resource.cs.ui.CsUIPlugin plugin = org.emftext.sdk.concretesyntax.resource.cs.ui.CsUIPlugin
                .getDefault();
        if (plugin == null) {
            return null;
        }

        ImageDescriptor descriptor = ImageDescriptor
                .createFromURL(FileLocator.find(plugin.getBundle(), path, null));
        if (ImageDescriptor.getMissingImageDescriptor().equals(descriptor) || descriptor == null) {
            // try loading image from any bundle
            try {
                URL pluginUrl = new URL(key);
                descriptor = ImageDescriptor.createFromURL(pluginUrl);
                if (ImageDescriptor.getMissingImageDescriptor().equals(descriptor) || descriptor == null) {
                    return null;
                }
            } catch (MalformedURLException mue) {
                org.emftext.sdk.concretesyntax.resource.cs.ui.CsUIPlugin
                        .logError("IconProvider can't load image (URL is malformed).", mue);
            }
        }
        return descriptor;
    }

}