common/plugins/org.eclipse.jpt.common.ui/src/org/eclipse/jpt/common/ui/internal/jface/AbstractItemStructuredStateProviderManager.java - dali/webtools.dali - Git at Google

 /*******************************************************************************
  * Copyright (c) 2008, 2015 Oracle. All rights reserved.
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0, which accompanies this distribution
  * and is available at https://www.eclipse.org/legal/epl-2.0/.
  *
  * Contributors:
  *     Oracle - initial API and implementation
  ******************************************************************************/
 package org.eclipse.jpt.common.ui.internal.jface;

 import java.util.HashMap;
 import org.eclipse.jface.resource.ResourceManager;
 import org.eclipse.jface.viewers.ILabelProviderListener;
 import org.eclipse.jface.viewers.LabelProviderChangedEvent;
 import org.eclipse.jface.viewers.StructuredViewer;
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.jpt.common.ui.internal.plugin.JptCommonUiPlugin;
 import org.eclipse.jpt.common.ui.internal.swt.widgets.DisplayTools;
 import org.eclipse.jpt.common.ui.jface.ItemContentProvider;
 import org.eclipse.jpt.common.ui.jface.ItemExtendedLabelProvider;
 import org.eclipse.jpt.common.ui.jface.ItemStructuredContentProvider;
 import org.eclipse.jpt.common.ui.jface.StructuredStateProvider;
 import org.eclipse.jpt.common.utility.exception.ExceptionHandler;
 import org.eclipse.jpt.common.utility.internal.ListenerList;
 import org.eclipse.jpt.common.utility.internal.ObjectTools;
 import org.eclipse.jpt.common.utility.internal.model.ModelTools;
 import org.eclipse.swt.graphics.Image;
 import com.ibm.icu.text.MessageFormat;

 /**
  * This provider maintains an input element content provider and a cache of item
  * label providers, each keyed by item. This allows the providers to listen to
  * the items and update the viewer as necessary.
  * <p>
  * <strong>NB:</strong> This class, if used as a label provider should typically
  * be used also as a content provider for the same viewer. Otherwise, the item
  * label providers will not be disposed until the viewer is disposed; because
  * the item label providers are disposed (here) as their associated items are
  * disposed by their item content providers, which are listening to the items.
  * This is only a problem if the items in the tree can be removed, thus leaking
  * stale item label providers in the manager's cache. The default behavior is
  * to disallow using the manager as only a label provider (see
  * {@link #checkViewer()}).
  *
  * @see ItemStructuredContentProvider
  * @see ItemExtendedLabelProvider
  */
 abstract class AbstractItemStructuredStateProviderManager<V extends StructuredViewer, CP extends ItemContentProvider, CPF extends ItemStructuredContentProvider.Factory>
 	implements StructuredStateProvider,
 				ItemStructuredContentProvider.Manager,
 				ItemExtendedLabelProvider.Manager
 {
 	/* private-protected */ V viewer;

 	private Object input;

 	/* private-protected */ final CPF itemContentProviderFactory;

 	private ItemStructuredContentProvider inputContentProvider;

 	private final ItemExtendedLabelProvider.Factory itemLabelProviderFactory;

 	/**
 	 * This maps <em>every</em> item in the view to its label provider
 	 * (<em>including</em> the {@link #input} item).
 	 */
 	private final HashMap<Object, ItemExtendedLabelProvider> itemLabelProviders = new HashMap<Object, ItemExtendedLabelProvider>();

 	private final ResourceManager resourceManager;

 	private final ListenerList<ILabelProviderListener> listenerList = ModelTools.listenerList();
 	private final ExceptionHandler exceptionHandler;

 	/* private-protected */ final static JptCommonUiPlugin PLUG_IN = JptCommonUiPlugin.instance();


 	/* private-protected */ AbstractItemStructuredStateProviderManager(
 			CPF itemContentProviderFactory,
 			ItemExtendedLabelProvider.Factory itemLabelProviderFactory,
 			ResourceManager resourceManager,
 			ExceptionHandler exceptionHandler
 	) {
 		super();
 		if (itemContentProviderFactory == null) {
 			throw new NullPointerException();
 		}
 		this.itemContentProviderFactory = itemContentProviderFactory;
 		if (itemLabelProviderFactory == null) {
 			throw new NullPointerException();
 		}
 		this.itemLabelProviderFactory = itemLabelProviderFactory;
 		if (resourceManager == null) {
 			throw new NullPointerException();
 		}
 		this.resourceManager = resourceManager;
 		if (exceptionHandler == null) {
 			throw new NullPointerException();
 		}
 		this.exceptionHandler = exceptionHandler;
 	}


 	// ********** structured content provider **********

 	/**
 	 * <em>API Commentary:</em> The viewer and the original input should be
 	 * passed to the provider's constructor; and this method should be passed
 	 * <em>only</em> the new input.
 	 */
 	public void inputChanged(Viewer v, Object oldInput, Object newInput) {
 		@SuppressWarnings("unchecked")
 		V temp = (V) v;
 		this.viewer = temp;
 		if (oldInput != newInput) {
 			if (this.inputContentProvider != null) {
 				this.disposeInputProviders();
 			}
 			this.input = newInput;
 			if (newInput != null) {
 				// build a label provider for the input because the viewer might
 				// use the input's label for a title etc. (e.g. the CommonViewer
 				// stores the input's label text on the frame list to enable
 				// "Back" and "Forward" navigation)
 				this.addLabelProvider(newInput);
 				this.inputContentProvider = this.itemContentProviderFactory.buildProvider(newInput, this);
 				this.addAll(newInput, this.inputContentProvider.getElements());
 			}
 		}
 	}

 	/**
 	 * Assume the input element passed to this method
 	 * is the same object as the "new input" passed (earlier) to
 	 * {@link #inputChanged(Viewer, Object, Object)},
 	 * and it is not <code>null</code>.
 	 * <p>
 	 * <em>API Commentary:</em> The input element should be passed to the
 	 * provider's constructor and {@link #inputChanged(Viewer, Object, Object)};
 	 * and this method should have <em>no</em> parameters.
 	 */
 	public Object[] getElements(Object inputElement) {
 		if (inputElement != this.input) {
 			String msg = MessageFormat.format("Mismatched input: this.input: '{0}' vs. inputElement: '{1}'", this.input, inputElement); //$NON-NLS-1$
 			IllegalArgumentException ex = new IllegalArgumentException(msg);
 			if (PLUG_IN != null) {
 				PLUG_IN.logError(ex);
 			} else {
 				ex.printStackTrace();
 			}
 		}
 		return this.inputContentProvider.getElements();
 	}


 	// ********** label provider **********

 	public Image getImage(Object element) {
 		return this.getItemLabelProvider(element).getImage();
 	}

 	public String getText(Object element) {
 		return this.getItemLabelProvider(element).getText();
 	}

 	public String getDescription(Object element) {
 		return this.getItemLabelProvider(element).getDescription();
 	}

 	/**
 	 * <strong>NB:</strong> We have a bug if this method ever returns
 	 * <code>null</code>.
 	 */
 	private ItemExtendedLabelProvider getItemLabelProvider(Object item) {
 		this.checkViewer();
 		return this.itemLabelProviders.get(item);
 	}

 	/**
 	 * The viewer passes itself to its content provider
 	 * (via {@link #inputChanged(Viewer, Object, Object)}); so the manager's
 	 * {@link #viewer} will be initialized by the time we get here if the
 	 * manager is also the viewer's content provider.
 	 */
 	private void checkViewer() {
 		if (this.viewer == null) {
 			String msg = "This manager must be both the viewer's content provider *and* the viewer's label provider."; //$NON-NLS-1$
 			IllegalStateException ex = new IllegalStateException(msg);
 			if (PLUG_IN != null) {
 				PLUG_IN.logError(ex);
 			} else {
 				ex.printStackTrace();
 			}
 		}
 	}


 	// ********** elements changed **********

 	/**
 	 * If the {@link #input} has changed out from under us, ignore the "event".
 	 */
 	public void elementsChanged(Object parent, Iterable<?> addedElements, Iterable<?> removedElements) {
 		this.checkUIThread();
 		if (parent == this.input) {
 			this.elementsChanged_(parent, addedElements, removedElements);
 		}
 	}

 	private void elementsChanged_(Object parent, Iterable<?> addedElements, Iterable<?> removedElements) {
 		this.addAll(parent, addedElements);
 		this.removeAll(removedElements);
 		this.viewer.refresh(false);  // not much else we can do here...
 	}

 	/**
 	 * @see #addAll(Object, Iterable)
 	 */
 	/* private-protected */ void addAll(Object parent, Object[] items) {
 		for (Object item : items) {
 			this.add(parent, item);
 		}
 	}

 	/**
 	 * Add the specified items' content and label providers.
 	 * <p>
 	 * Pre-condition: Executing on the UI thread.
 	 */
 	/* private-protected */ void addAll(Object parent, Iterable<?> items) {
 		for (Object item : items) {
 			this.add(parent, item);
 		}
 	}

 	/**
 	 * Add the specified item's content and label providers.
 	 * <p>
 	 * Pre-condition: Executing on the UI thread.
 	 */
 	/* private-protected */ void add(@SuppressWarnings("unused") Object parent, Object item) {
 		this.addLabelProvider(item);
 	}

 	private void addLabelProvider(Object item) {
 		this.itemLabelProviders.put(item, this.itemLabelProviderFactory.buildProvider(item, this));
 	}

 	/**
 	 * @see #removeAll(Iterable)
 	 */
 	/* private-protected */ void removeAll(Object[] items) {
 		for (Object item : items) {
 			this.remove(item);
 		}
 	}

 	/**
 	 * Dispose the specified items' content and label providers.
 	 * <p>
 	 * Pre-condition: Executing on the UI thread.
 	 */
 	/* private-protected */ void removeAll(Iterable<?> items) {
 		for (Object item : items) {
 			this.remove(item);
 		}
 	}

 	/**
 	 * Dispose the specified item's content and label providers.
 	 * <p>
 	 * Pre-condition: Executing on the UI thread.
 	 */
 	/* private-protected */ void remove(Object item) {
 		this.removeLabelProvider(item);
 	}

 	private void removeLabelProvider(Object item) {
 		this.itemLabelProviders.get(item).dispose();
 		this.itemLabelProviders.remove(item);
 	}


 	// ********** label changed **********

 	/**
 	 * If the specified item has been removed from under us, ignore the "event".
 	 */
 	public void labelChanged(Object item) {
 		this.checkUIThread();
 		if (this.getItemLabelProvider(item) != null) {
 			this.labelChanged_(item);
 		}
 	}

 	private void labelChanged_(Object item) {
 		this.fireLabelProviderChanged(new LabelProviderChangedEvent(this, item));
 	}


 	// ********** description changed **********

 	/**
 	 * If the specified item has been removed from under us, ignore the "event".
 	 */
 	public void descriptionChanged(Object item) {
 		this.checkUIThread();
 		if (this.getItemLabelProvider(item) != null) {
 			this.descriptionChanged_(item);
 		}
 	}

 	private void descriptionChanged_(@SuppressWarnings("unused") Object item) {
 		// NOP - currently there is no way affect the status bar;
 		// it is updated when the viewer's selection changes
 	}


 	// ********** listeners **********

 	public void addListener(ILabelProviderListener listener) {
 		this.listenerList.add(listener);
 	}

 	public void removeListener(ILabelProviderListener listener) {
 		this.listenerList.remove(listener);
 	}

 	public boolean isLabelProperty(Object element, String property) {
 		return this.itemLabelProviders.get(element).isLabelProperty(property);
 	}

 	/* private-protected */ void fireLabelProviderChanged(LabelProviderChangedEvent event) {
 		for (ILabelProviderListener listener : this.listenerList) {
 			try {
 				listener.labelProviderChanged(event);
 			} catch (Throwable t) {
 				this.exceptionHandler.handleException(t);
 			}
 		}
 	}

 	// ********** dispose **********

 	/**
 	 * Typically, the provider's input is set to <code>null</code> (via
 	 * {@link #inputChanged(Viewer, Object, Object) inputChanged(...)}) <em>before</em> the
 	 * provider is disposed
 	 * (see {@link org.eclipse.jface.viewers.ContentViewer#handleDispose(org.eclipse.swt.events.DisposeEvent)
 	 * ContentViewer.handleDispose(...)}).
 	 * But {@link org.eclipse.ui.navigator.CommonViewer CommonViewer}
 	 * disposes its {@link org.eclipse.ui.navigator.INavigatorContentService
 	 * content service} (and its delegate content providers) <em>before</em> the input
 	 * is set to <code>null</code>
 	 * (see {@link org.eclipse.ui.navigator.CommonViewer#handleDispose(org.eclipse.swt.events.DisposeEvent)
 	 * CommonViewer.handleDispose(...)}).
 	 * This is <em>intentional</em>;
 	 * see the comment in {@link org.eclipse.ui.internal.navigator.NavigatorContentService#updateService(Viewer, Object, Object)
 	 * NavigatorContentService.updateService(...)}.
 	 */
 	public void dispose() {
 		if (this.inputContentProvider != null) {
 			this.disposeInputProviders();
 			this.input = null;
 		}
 		// the input is set to null before the content and label providers are disposed,
 		// so there is no need to dispose the item providers here - they are already gone...
 		if ( ! this.itemLabelProviders.isEmpty()) {
 			String msg = MessageFormat.format("Not all item label providers were disposed: {0}", this.itemLabelProviders); //$NON-NLS-1$
 			IllegalStateException ex = new IllegalStateException(msg);
 			if (PLUG_IN != null) {
 				PLUG_IN.logError(ex);
 			} else {
 				ex.printStackTrace();
 			}
 		}
 	}

 	private void disposeInputProviders() {
 		this.removeAll(this.inputContentProvider.getElements());
 		this.inputContentProvider.dispose();
 		this.inputContentProvider = null;
 		this.removeLabelProvider(this.input);
 	}


 	// ********** misc **********

 	public StructuredViewer getViewer() {
 		return this.viewer;
 	}

 	public ResourceManager getResourceManager() {
 		return this.resourceManager;
 	}

 	/* private-protected */ void checkUIThread() {
 		DisplayTools.checkUIThread(this.viewer);
 	}

 	@Override
 	public String toString() {
 		return ObjectTools.toString(this);
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2008, 2015 Oracle. All rights reserved.
	* This program and the accompanying materials are made available under the
	* terms of the Eclipse Public License 2.0, which accompanies this distribution
	* and is available at https://www.eclipse.org/legal/epl-2.0/.
	*
	* Contributors:
	* Oracle - initial API and implementation
	******************************************************************************/
	package org.eclipse.jpt.common.ui.internal.jface;

	import java.util.HashMap;
	import org.eclipse.jface.resource.ResourceManager;
	import org.eclipse.jface.viewers.ILabelProviderListener;
	import org.eclipse.jface.viewers.LabelProviderChangedEvent;
	import org.eclipse.jface.viewers.StructuredViewer;
	import org.eclipse.jface.viewers.Viewer;
	import org.eclipse.jpt.common.ui.internal.plugin.JptCommonUiPlugin;
	import org.eclipse.jpt.common.ui.internal.swt.widgets.DisplayTools;
	import org.eclipse.jpt.common.ui.jface.ItemContentProvider;
	import org.eclipse.jpt.common.ui.jface.ItemExtendedLabelProvider;
	import org.eclipse.jpt.common.ui.jface.ItemStructuredContentProvider;
	import org.eclipse.jpt.common.ui.jface.StructuredStateProvider;
	import org.eclipse.jpt.common.utility.exception.ExceptionHandler;
	import org.eclipse.jpt.common.utility.internal.ListenerList;
	import org.eclipse.jpt.common.utility.internal.ObjectTools;
	import org.eclipse.jpt.common.utility.internal.model.ModelTools;
	import org.eclipse.swt.graphics.Image;
	import com.ibm.icu.text.MessageFormat;

	/**
	* This provider maintains an input element content provider and a cache of item
	* label providers, each keyed by item. This allows the providers to listen to
	* the items and update the viewer as necessary.
	* <p>
	* <strong>NB:</strong> This class, if used as a label provider should typically
	* be used also as a content provider for the same viewer. Otherwise, the item
	* label providers will not be disposed until the viewer is disposed; because
	* the item label providers are disposed (here) as their associated items are
	* disposed by their item content providers, which are listening to the items.
	* This is only a problem if the items in the tree can be removed, thus leaking
	* stale item label providers in the manager's cache. The default behavior is
	* to disallow using the manager as only a label provider (see
	* {@link #checkViewer()}).
	*
	* @see ItemStructuredContentProvider
	* @see ItemExtendedLabelProvider
	*/
	abstract class AbstractItemStructuredStateProviderManager<V extends StructuredViewer, CP extends ItemContentProvider, CPF extends ItemStructuredContentProvider.Factory>
	implements StructuredStateProvider,
	ItemStructuredContentProvider.Manager,
	ItemExtendedLabelProvider.Manager
	{
	/* private-protected */ V viewer;

	private Object input;

	/* private-protected */ final CPF itemContentProviderFactory;

	private ItemStructuredContentProvider inputContentProvider;

	private final ItemExtendedLabelProvider.Factory itemLabelProviderFactory;

	/**
	* This maps <em>every</em> item in the view to its label provider
	* (<em>including</em> the {@link #input} item).
	*/
	private final HashMap<Object, ItemExtendedLabelProvider> itemLabelProviders = new HashMap<Object, ItemExtendedLabelProvider>();

	private final ResourceManager resourceManager;

	private final ListenerList<ILabelProviderListener> listenerList = ModelTools.listenerList();
	private final ExceptionHandler exceptionHandler;

	/* private-protected */ final static JptCommonUiPlugin PLUG_IN = JptCommonUiPlugin.instance();


	/* private-protected */ AbstractItemStructuredStateProviderManager(
	CPF itemContentProviderFactory,
	ItemExtendedLabelProvider.Factory itemLabelProviderFactory,
	ResourceManager resourceManager,
	ExceptionHandler exceptionHandler
	) {
	super();
	if (itemContentProviderFactory == null) {
	throw new NullPointerException();
	}
	this.itemContentProviderFactory = itemContentProviderFactory;
	if (itemLabelProviderFactory == null) {
	throw new NullPointerException();
	}
	this.itemLabelProviderFactory = itemLabelProviderFactory;
	if (resourceManager == null) {
	throw new NullPointerException();
	}
	this.resourceManager = resourceManager;
	if (exceptionHandler == null) {
	throw new NullPointerException();
	}
	this.exceptionHandler = exceptionHandler;
	}


	// ******** structured content provider ********

	/**
	* <em>API Commentary:</em> The viewer and the original input should be
	* passed to the provider's constructor; and this method should be passed
	* <em>only</em> the new input.
	*/
	public void inputChanged(Viewer v, Object oldInput, Object newInput) {
	@SuppressWarnings("unchecked")
	V temp = (V) v;
	this.viewer = temp;
	if (oldInput != newInput) {
	if (this.inputContentProvider != null) {
	this.disposeInputProviders();
	}
	this.input = newInput;
	if (newInput != null) {
	// build a label provider for the input because the viewer might
	// use the input's label for a title etc. (e.g. the CommonViewer
	// stores the input's label text on the frame list to enable
	// "Back" and "Forward" navigation)
	this.addLabelProvider(newInput);
	this.inputContentProvider = this.itemContentProviderFactory.buildProvider(newInput, this);
	this.addAll(newInput, this.inputContentProvider.getElements());
	}
	}
	}

	/**
	* Assume the input element passed to this method
	* is the same object as the "new input" passed (earlier) to
	* {@link #inputChanged(Viewer, Object, Object)},
	* and it is not <code>null</code>.
	* <p>
	* <em>API Commentary:</em> The input element should be passed to the
	* provider's constructor and {@link #inputChanged(Viewer, Object, Object)};
	* and this method should have <em>no</em> parameters.
	*/
	public Object[] getElements(Object inputElement) {
	if (inputElement != this.input) {
	String msg = MessageFormat.format("Mismatched input: this.input: '{0}' vs. inputElement: '{1}'", this.input, inputElement); //$NON-NLS-1$
	IllegalArgumentException ex = new IllegalArgumentException(msg);
	if (PLUG_IN != null) {
	PLUG_IN.logError(ex);
	} else {
	ex.printStackTrace();
	}
	}
	return this.inputContentProvider.getElements();
	}


	// ******** label provider ********

	public Image getImage(Object element) {
	return this.getItemLabelProvider(element).getImage();
	}

	public String getText(Object element) {
	return this.getItemLabelProvider(element).getText();
	}

	public String getDescription(Object element) {
	return this.getItemLabelProvider(element).getDescription();
	}

	/**
	* <strong>NB:</strong> We have a bug if this method ever returns
	* <code>null</code>.
	*/
	private ItemExtendedLabelProvider getItemLabelProvider(Object item) {
	this.checkViewer();
	return this.itemLabelProviders.get(item);
	}

	/**
	* The viewer passes itself to its content provider
	* (via {@link #inputChanged(Viewer, Object, Object)}); so the manager's
	* {@link #viewer} will be initialized by the time we get here if the
	* manager is also the viewer's content provider.
	*/
	private void checkViewer() {
	if (this.viewer == null) {
	String msg = "This manager must be both the viewer's content provider and the viewer's label provider."; //$NON-NLS-1$
	IllegalStateException ex = new IllegalStateException(msg);
	if (PLUG_IN != null) {
	PLUG_IN.logError(ex);
	} else {
	ex.printStackTrace();
	}
	}
	}


	// ******** elements changed ********

	/**
	* If the {@link #input} has changed out from under us, ignore the "event".
	*/
	public void elementsChanged(Object parent, Iterable<?> addedElements, Iterable<?> removedElements) {
	this.checkUIThread();
	if (parent == this.input) {
	this.elementsChanged_(parent, addedElements, removedElements);
	}
	}

	private void elementsChanged_(Object parent, Iterable<?> addedElements, Iterable<?> removedElements) {
	this.addAll(parent, addedElements);
	this.removeAll(removedElements);
	this.viewer.refresh(false); // not much else we can do here...
	}

	/**
	* @see #addAll(Object, Iterable)
	*/
	/* private-protected */ void addAll(Object parent, Object[] items) {
	for (Object item : items) {
	this.add(parent, item);
	}
	}

	/**
	* Add the specified items' content and label providers.
	* <p>
	* Pre-condition: Executing on the UI thread.
	*/
	/* private-protected */ void addAll(Object parent, Iterable<?> items) {
	for (Object item : items) {
	this.add(parent, item);
	}
	}

	/**
	* Add the specified item's content and label providers.
	* <p>
	* Pre-condition: Executing on the UI thread.
	*/
	/* private-protected */ void add(@SuppressWarnings("unused") Object parent, Object item) {
	this.addLabelProvider(item);
	}

	private void addLabelProvider(Object item) {
	this.itemLabelProviders.put(item, this.itemLabelProviderFactory.buildProvider(item, this));
	}

	/**
	* @see #removeAll(Iterable)
	*/
	/* private-protected */ void removeAll(Object[] items) {
	for (Object item : items) {
	this.remove(item);
	}
	}

	/**
	* Dispose the specified items' content and label providers.
	* <p>
	* Pre-condition: Executing on the UI thread.
	*/
	/* private-protected */ void removeAll(Iterable<?> items) {
	for (Object item : items) {
	this.remove(item);
	}
	}

	/**
	* Dispose the specified item's content and label providers.
	* <p>
	* Pre-condition: Executing on the UI thread.
	*/
	/* private-protected */ void remove(Object item) {
	this.removeLabelProvider(item);
	}

	private void removeLabelProvider(Object item) {
	this.itemLabelProviders.get(item).dispose();
	this.itemLabelProviders.remove(item);
	}


	// ******** label changed ********

	/**
	* If the specified item has been removed from under us, ignore the "event".
	*/
	public void labelChanged(Object item) {
	this.checkUIThread();
	if (this.getItemLabelProvider(item) != null) {
	this.labelChanged_(item);
	}
	}

	private void labelChanged_(Object item) {
	this.fireLabelProviderChanged(new LabelProviderChangedEvent(this, item));
	}


	// ******** description changed ********

	/**
	* If the specified item has been removed from under us, ignore the "event".
	*/
	public void descriptionChanged(Object item) {
	this.checkUIThread();
	if (this.getItemLabelProvider(item) != null) {
	this.descriptionChanged_(item);
	}
	}

	private void descriptionChanged_(@SuppressWarnings("unused") Object item) {
	// NOP - currently there is no way affect the status bar;
	// it is updated when the viewer's selection changes
	}


	// ******** listeners ********

	public void addListener(ILabelProviderListener listener) {
	this.listenerList.add(listener);
	}

	public void removeListener(ILabelProviderListener listener) {
	this.listenerList.remove(listener);
	}

	public boolean isLabelProperty(Object element, String property) {
	return this.itemLabelProviders.get(element).isLabelProperty(property);
	}

	/* private-protected */ void fireLabelProviderChanged(LabelProviderChangedEvent event) {
	for (ILabelProviderListener listener : this.listenerList) {
	try {
	listener.labelProviderChanged(event);
	} catch (Throwable t) {
	this.exceptionHandler.handleException(t);
	}
	}
	}

	// ******** dispose ********

	/**
	* Typically, the provider's input is set to <code>null</code> (via
	* {@link #inputChanged(Viewer, Object, Object) inputChanged(...)}) <em>before</em> the
	* provider is disposed
	* (see {@link org.eclipse.jface.viewers.ContentViewer#handleDispose(org.eclipse.swt.events.DisposeEvent)
	* ContentViewer.handleDispose(...)}).
	* But {@link org.eclipse.ui.navigator.CommonViewer CommonViewer}
	* disposes its {@link org.eclipse.ui.navigator.INavigatorContentService
	* content service} (and its delegate content providers) <em>before</em> the input
	* is set to <code>null</code>
	* (see {@link org.eclipse.ui.navigator.CommonViewer#handleDispose(org.eclipse.swt.events.DisposeEvent)
	* CommonViewer.handleDispose(...)}).
	* This is <em>intentional</em>;
	* see the comment in {@link org.eclipse.ui.internal.navigator.NavigatorContentService#updateService(Viewer, Object, Object)
	* NavigatorContentService.updateService(...)}.
	*/
	public void dispose() {
	if (this.inputContentProvider != null) {
	this.disposeInputProviders();
	this.input = null;
	}
	// the input is set to null before the content and label providers are disposed,
	// so there is no need to dispose the item providers here - they are already gone...
	if ( ! this.itemLabelProviders.isEmpty()) {
	String msg = MessageFormat.format("Not all item label providers were disposed: {0}", this.itemLabelProviders); //$NON-NLS-1$
	IllegalStateException ex = new IllegalStateException(msg);
	if (PLUG_IN != null) {
	PLUG_IN.logError(ex);
	} else {
	ex.printStackTrace();
	}
	}
	}

	private void disposeInputProviders() {
	this.removeAll(this.inputContentProvider.getElements());
	this.inputContentProvider.dispose();
	this.inputContentProvider = null;
	this.removeLabelProvider(this.input);
	}


	// ******** misc ********

	public StructuredViewer getViewer() {
	return this.viewer;
	}

	public ResourceManager getResourceManager() {
	return this.resourceManager;
	}

	/* private-protected */ void checkUIThread() {
	DisplayTools.checkUIThread(this.viewer);
	}

	@Override
	public String toString() {
	return ObjectTools.toString(this);
	}
	}