TestLightweightDecoratorContributor.java

/*******************************************************************************
 * Copyright (c) 2004, 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
 *******************************************************************************/
package org.eclipse.ui.tests.decorators;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.viewers.IDecoration;
import org.eclipse.jface.viewers.ILabelProviderListener;
import org.eclipse.jface.viewers.ILightweightLabelDecorator;
import org.eclipse.jface.viewers.LabelProviderChangedEvent;
import org.eclipse.ui.tests.TestPlugin;

public class TestLightweightDecoratorContributor implements
        ILightweightLabelDecorator {

    public static TestLightweightDecoratorContributor contributor;

    private Set listeners = new HashSet();

    public static String DECORATOR_SUFFIX = "_SUFFIX";

    public static String DECORATOR_PREFIX = "PREFIX_";

    private ImageDescriptor descriptor;

    public TestLightweightDecoratorContributor() {
        contributor = this;
    }

    /*
     * @see IBaseLabelProvider#addListener(ILabelProviderListener)
     */
    public void addListener(ILabelProviderListener listener) {
        listeners.add(listener);
    }

    /*
     * @see IBaseLabelProvider#dispose()
     */
    public void dispose() {
        contributor = null;
        listeners = new HashSet();
    }

    /*
     * @see IBaseLabelProvider#isLabelProperty(Object, String)
     */
    public boolean isLabelProperty(Object element, String property) {
        return false;
    }

    /*
     * @see IBaseLabelProvider#removeListener(ILabelProviderListener)
     */
    public void removeListener(ILabelProviderListener listener) {
        listeners.remove(listener);
    }

    /**
     * Refresh the listeners to update the decorators for 
     * element.
     */

    public void refreshListeners(Object element) {
        Iterator iterator = listeners.iterator();
        while (iterator.hasNext()) {
            LabelProviderChangedEvent event = new LabelProviderChangedEvent(
                    this, element);
            ((ILabelProviderListener) iterator.next())
                    .labelProviderChanged(event);
        }
    }

    /**
     * @see org.eclipse.jface.viewers.ILightweightLabelDecorator#getOverlay(java.lang.Object)
     */
    public ImageDescriptor getOverlay(Object element) {
        Assert.isTrue(element instanceof IResource);
        if (descriptor == null) {
            URL source = TestPlugin.getDefault().getDescriptor()
                    .getInstallURL();
            try {
                descriptor = ImageDescriptor.createFromURL(new URL(source,
                        "icons/binary_co.gif"));
            } catch (MalformedURLException exception) {
                return null;
            }
        }
        return descriptor;

    }

    /**
     * @see org.eclipse.jface.viewers.ILightweightLabelDecorator#decorate(java.lang.Object, org.eclipse.jface.viewers.IDecoration)
     */
    public void decorate(Object element, IDecoration decoration) {
        decoration.addOverlay(getOverlay(element));
        decoration.addPrefix(DECORATOR_PREFIX);
        decoration.addSuffix(DECORATOR_SUFFIX);
    }

}