ItemProviderDecorator.java

/**
 * <copyright> 
 *
 * Copyright (c) 2002, 2009 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 - Initial API and implementation
 *
 * </copyright>
 *
 * $Id: ItemProviderDecorator.java,v 1.5 2008/01/15 17:15:41 emerks Exp $
 */
package net.enilink.komma.edit.provider;

import java.util.Collection;
import java.util.List;

import net.enilink.komma.common.adapter.IAdapterFactory;
import net.enilink.komma.common.command.ICommand;
import net.enilink.komma.common.notify.INotification;
import net.enilink.komma.common.notify.INotificationBroadcaster;
import net.enilink.komma.common.notify.INotificationListener;
import net.enilink.komma.common.notify.INotifier;
import net.enilink.komma.common.notify.NotificationFilter;
import net.enilink.komma.common.notify.NotificationSupport;
import net.enilink.komma.common.util.ICollector;
import net.enilink.komma.edit.command.CommandParameter;
import net.enilink.komma.edit.domain.IEditingDomain;

/**
 * This implementation provides a convenient reusable base for item providers
 * that will be used as decorators of other item providers. Default
 * implementations for the following interfaces are provided:
 * {@link IEditingDomainItemProvider}, {@link IItemLabelProvider},
 * {@link IItemPropertySource}, {@link IStructuredItemContentProvider},
 * {@link IItemFontProvider}, {@link IItemColorProvider},
 * {@link ITableItemFontProvider}, {@link ITableItemColorProvider},
 * {@link ITableItemLabelProvider}, and {@link ITreeItemContentProvider}, and
 * {@link IUpdateableItemText#getUpdateableText}.
 */
public class ItemProviderDecorator implements
		INotificationListener<INotification>, IItemProviderDecorator,
		INotificationBroadcaster<INotification>, IDisposable {
	/**
	 * This keeps track of the adapter factory that created this adaptor. It is
	 * also used as the key/type for this adapter.
	 */
	protected IAdapterFactory adapterFactory;

	/**
	 * This is used to implement {@link IChangeNotifier}.
	 */
	protected NotificationSupport<INotification> changeNotifier;

	/**
	 * This keeps track of the item provider being decorated.
	 */
	protected INotifier<INotification> decoratedItemProvider;

	/**
	 * An instance is created from an adapter factory. The factory is used as a
	 * key so that we always know which factory created this adapter.
	 */
	public ItemProviderDecorator(IAdapterFactory adapterFactory) {
		this.adapterFactory = adapterFactory;
	}

	public void addListener(INotificationListener<INotification> listener) {
		if (changeNotifier == null) {
			changeNotifier = new NotificationSupport<INotification>();
		}
		changeNotifier.addListener(listener);
	}

	/**
	 * This implements {@link IEditingDomainItemProvider#createCommand
	 * IEditingDomainItemProvider.createCommand} by delegating to
	 * <code>(IEditingDomainItemProvider)</code>{@link #decoratedItemProvider}.
	 */
	public ICommand createCommand(Object object, IEditingDomain domain,
			Class<? extends ICommand> commandClass,
			CommandParameter commandParameter) {
		return ((IEditingDomainItemProvider) decoratedItemProvider)
				.createCommand(object, domain, commandClass, commandParameter);
		/*
		 * // For convenience of overrides, this class delegates to the various
		 * createXyzCommand methods first. if (commandClass == SetCommand.class)
		 * { return createSetCommand(domain, commandParameter.getOwner(),
		 * commandParameter.getFeature(), commandParameter.getValue()); } else
		 * if (commandClass == CopyCommand.class) { return
		 * createCopyCommand(domain, commandParameter.getOwner(),
		 * (CopyCommand.Helper)commandParameter.getValue()); } else if
		 * (commandClass == CreateCopyCommand.class) { return
		 * createCreateCopyCommand(domain, commandParameter.getOwner(),
		 * (CopyCommand.Helper)commandParameter.getValue()); } else if
		 * (commandClass == InitializeCopyCommand.class) { return
		 * createInitializeCopyCommand(domain, commandParameter.getOwner(),
		 * (CopyCommand.Helper)commandParameter.getValue()); } else if
		 * (commandClass == RemoveCommand.class) { return
		 * createRemoveCommand(domain, commandParameter.getOwner(),
		 * commandParameter.getFeature(), commandParameter.getCollection()); }
		 * else if (commandClass == AddCommand.class) { return createAddCommand
		 * (domain, commandParameter.getOwner(), commandParameter.getFeature(),
		 * commandParameter.getCollection(), commandParameter.getIndex()); }
		 * else if (commandClass == MoveCommand.class) { return
		 * createMoveCommand (domain, commandParameter.getOwner(),
		 * commandParameter.getFeature(), commandParameter.getValue(),
		 * commandParameter.getIndex()); } else if (commandClass ==
		 * ReplaceCommand.class) { return createReplaceCommand (domain,
		 * commandParameter.getOwner(), commandParameter.getFeature(),
		 * commandParameter.getValue(), commandParameter.getCollection()); }
		 * else if (commandClass == DragAndDropCommand.class) {
		 * DragAndDropCommand.Detail detail =
		 * (DragAndDropCommand.Detail)commandParameter.getFeature(); return
		 * createDragAndDropCommand (domain, commandParameter.getOwner(),
		 * detail.location, detail.operations, detail.operation,
		 * commandParameter.getCollection()); } else { return
		 * ((IEditingDomainItemProvider
		 * )decoratedItemProvider).createCommand(object, domain, commandClass,
		 * commandParameter); }
		 */
	}

	public void dispose() {
		if (decoratedItemProvider != null) {
			decoratedItemProvider.removeListener(this);
		}
	}

	/**
	 * This provides access to the factory.
	 */
	public IAdapterFactory getAdapterFactory() {
		return adapterFactory;
	}

	/**
	 * This implements {@link IItemColorProvider#getBackground
	 * IItemColorProvider.getBackground} by delegating to
	 * <code>(IItemColorProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getBackground(Object object) {
		return ((IItemColorProvider) decoratedItemProvider)
				.getBackground(object);
	}

	/**
	 * This implements {@link ITableItemColorProvider#getBackground
	 * ITableItemColorProvider.getBackground} by delegating to
	 * <code>(ITableItemColorProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getBackground(Object object, int columnIndex) {
		return ((ITableItemColorProvider) decoratedItemProvider).getBackground(
				object, columnIndex);
	}

	/**
	 * This implements {@link ITreeItemContentProvider#getChildren
	 * ITreeItemContentProvider.getChildren} by delegating to
	 * <code>(ITreeItemContentProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Collection<?> getChildren(Object object) {
		return ((ITreeItemContentProvider) decoratedItemProvider)
				.getChildren(object);
	}

	/**
	 * This implements {@link ITableItemLabelProvider#getColumnImage
	 * ITableItemLabelProvider.getColumnImage} by delegating to
	 * <code>(ITableItemLabelProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getColumnImage(Object object, int columnIndex) {
		return ((ITableItemLabelProvider) decoratedItemProvider)
				.getColumnImage(object, columnIndex);
	}

	/**
	 * This implements {@link ITableItemLabelProvider#getColumnText
	 * ITableItemLabelProvider.getColumnText} by delegating to
	 * <code>(ITableItemLabelProvider)</code>{@link #decoratedItemProvider}.
	 */
	public String getColumnText(Object object, int columnIndex) {
		return ((ITableItemLabelProvider) decoratedItemProvider).getColumnText(
				object, columnIndex);
	}

	/**
	 * This returns the item provider that this decorates.
	 */
	public INotifier<INotification> getDecoratedItemProvider() {
		return decoratedItemProvider;
	}

	/**
	 * This implements {@link IItemPropertySource#getEditableValue
	 * IItemPropertySource.getEditableValue} by delegating to
	 * <code>(IItemPropertySource)</code>{@link #decoratedItemProvider}.
	 */
	public Object getEditableValue(Object object) {
		return ((IItemPropertySource) decoratedItemProvider)
				.getEditableValue(object);
	}

	/**
	 * This implements {@link IStructuredItemContentProvider#getElements
	 * IStructuredItemContentProvider.getElements} by delegating to
	 * <code>(IStructuredItemContentProvider)</code>
	 * {@link #decoratedItemProvider}.
	 */
	public Collection<?> getElements(Object object) {
		return ((IStructuredItemContentProvider) decoratedItemProvider)
				.getElements(object);
	}

	public NotificationFilter<INotification> getFilter() {
		return null;
	}

	/**
	 * This implements {@link IItemFontProvider#getFont
	 * IItemFontProvider.getFont} by delegating to
	 * <code>(IItemFontProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getFont(Object object) {
		return ((IItemFontProvider) decoratedItemProvider).getFont(object);
	}

	/**
	 * This implements {@link ITableItemFontProvider#getFont
	 * ITableItemFontProvider.getFont} by delegating to
	 * <code>(IItemFontProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getFont(Object object, int columnIndex) {
		return ((ITableItemFontProvider) decoratedItemProvider).getFont(object,
				columnIndex);
	}

	/**
	 * This implements {@link IItemColorProvider#getForeground
	 * IItemColorProvider.getForeground} by delegating to
	 * <code>(IItemColorProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getForeground(Object object) {
		return ((IItemColorProvider) decoratedItemProvider)
				.getForeground(object);
	}

	/**
	 * This implements {@link ITableItemColorProvider#getForeground
	 * ITableItemColorProvider.getForeground} by delegating to
	 * <code>(ITableItemColorProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getForeground(Object object, int columnIndex) {
		return ((ITableItemColorProvider) decoratedItemProvider).getForeground(
				object, columnIndex);
	}

	/**
	 * This implements {@link IItemLabelProvider#getImage
	 * IItemLabelProvider.getImage} by delegating to
	 * <code>(IItemLabelProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getImage(Object object) {
		return ((IItemLabelProvider) decoratedItemProvider).getImage(object);
	}

	/**
	 * This implements {@link IEditingDomainItemProvider#getNewChildDescriptors
	 * IEditingDomainItemProvider.getNewChildDescriptors} by delegating to
	 * <code>(IEditingDomainItemProvider)</code>{@link #decoratedItemProvider}.
	 */
	public void getNewChildDescriptors(Object object,
			IEditingDomain editingDomain, Object sibling,
			ICollector<Object> descriptors) {
		((IEditingDomainItemProvider) decoratedItemProvider)
				.getNewChildDescriptors(object, editingDomain, sibling,
						descriptors);
	}

	/**
	 * This implements {@link ITreeItemContentProvider#getParent
	 * ITreeItemContentProvider.getParent} by delegating to
	 * <code>(ITreeItemContentProvider)</code>{@link #decoratedItemProvider}.
	 */
	public Object getParent(Object object) {
		return ((ITreeItemContentProvider) decoratedItemProvider)
				.getParent(object);
	}

	/**
	 * This implements {@link IItemPropertySource#getPropertyDescriptors
	 * IItemPropertySource.getPropertyDescriptors} by delegating to
	 * <code>(IItemPropertySource)</code>{@link #decoratedItemProvider}.
	 */
	public IItemPropertyDescriptor getPropertyDescriptor(Object object,
			Object propertyId) {
		return ((IItemPropertySource) decoratedItemProvider)
				.getPropertyDescriptor(object, propertyId);
	}

	/**
	 * This implements {@link IItemPropertySource#getPropertyDescriptors
	 * IItemPropertySource.getPropertyDescriptors} by delegating to
	 * <code>(IItemPropertySource)</code>{@link #decoratedItemProvider}.
	 */
	public List<IItemPropertyDescriptor> getPropertyDescriptors(Object object) {
		return ((IItemPropertySource) decoratedItemProvider)
				.getPropertyDescriptors(object);
	}

	/**
	 * This implements {@link IItemLabelProvider#getText
	 * IItemLabelProvider.getText} by delegating to
	 * <code>(IItemLabelProvider)</code>{@link #decoratedItemProvider}.
	 */
	public String getText(Object object) {
		return ((IItemLabelProvider) decoratedItemProvider).getText(object);
	}

	/**
	 * This implements {@link IUpdateableItemText#getUpdateableText
	 * IUpdateableItemText.getUpdateableText} by delegating to
	 * <code>(IUpdateableItemText)</code>{@link #decoratedItemProvider}.
	 */
	public String getUpdateableText(Object object) {
		return ((IUpdateableItemText) decoratedItemProvider)
				.getUpdateableText(object);
	}

	/**
	 * This implements {@link ITreeItemContentProvider#hasChildren
	 * ITreeItemContentProvider.hasChildren} by delegating to
	 * <code>(ITreeItemContentProvider)</code>{@link #decoratedItemProvider}.
	 */
	public boolean hasChildren(Object object) {
		return ((ITreeItemContentProvider) decoratedItemProvider)
				.hasChildren(object);
	}

	/**
	 * This returns true, only if this adapter was created by the given factory;
	 * the adapter factory is used as the type key.
	 */
	public boolean isAdapterForType(Object type) {
		return type == adapterFactory;
	}

	@SuppressWarnings("unchecked")
	public void fireNotifications(
			Collection<? extends INotification> notifications) {
		if (adapterFactory instanceof INotificationBroadcaster<?>) {
			INotificationBroadcaster<INotification> adapterFactoryChangeNotifier = (INotificationBroadcaster<INotification>) adapterFactory;
			adapterFactoryChangeNotifier.fireNotifications(notifications);
		}
		if (changeNotifier != null) {
			changeNotifier.fireNotifications(notifications);
		}
	}

	/*
	 * protected Command createSetCommand(EditingDomain domain, Object owner,
	 * Object feature, Object value) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, SetCommand.class, new CommandParameter(owner, feature, value)); }
	 * 
	 * protected Command createCopyCommand(EditingDomain domain, Object owner,
	 * CopyCommand.Helper helper) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, CopyCommand.class, new CommandParameter(owner, null, helper)); }
	 * 
	 * protected Command createCreateCopyCommand(EditingDomain domain, Object
	 * owner, CopyCommand.Helper helper) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, CreateCopyCommand.class, new CommandParameter(owner, null,
	 * helper)); }
	 * 
	 * protected Command createInitializeCopyCommand(EditingDomain domain,
	 * Object owner, CopyCommand.Helper helper) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, InitializeCopyCommand.class, new CommandParameter(owner, null,
	 * helper)); }
	 * 
	 * protected Command createRemoveCommand(EditingDomain domain, Object owner,
	 * Object feature, Collection collection) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, RemoveCommand.class, new CommandParameter(owner, feature,
	 * collection)); }
	 * 
	 * protected Command createReplaceCommand(EditingDomain domain, Object
	 * owner, Object feature, Object value, Collection collection) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, ReplaceCommand.class, new CommandParameter(owner, feature, value,
	 * collection)); }
	 * 
	 * protected Command createAddCommand(EditingDomain domain, Object owner,
	 * Object feature, Collection collection, int index) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, ReplaceCommand.class, new CommandParameter(owner, feature,
	 * collection, index)); }
	 * 
	 * protected Command createMoveCommand(EditingDomain domain, Object owner,
	 * Object feature, Object value, int index) { return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, ReplaceCommand.class, new CommandParameter(owner, feature, value,
	 * index)); }
	 * 
	 * protected Command createDragAndDropCommand (EditingDomain domain, Object
	 * owner, float location, int operations, int operation, Collection
	 * collection) { DragAndDropCommand.Detail detail = new
	 * DragAndDropCommand.Detail(location, operations, operation); return
	 * ((IEditingDomainItemProvider)decoratedItemProvider).createCommand (owner,
	 * domain, DragAndDropCommand.class, new CommandParameter(owner, detail,
	 * collection)); }
	 */

	public void notifyChanged(Collection<? extends INotification> notifications) {
		fireNotifications(notifications);
	}

	public void removeListener(INotificationListener<INotification> listener) {
		if (changeNotifier != null) {
			changeNotifier.removeListener(listener);
		}
	}

	/**
	 * This sets the item provider that this decorates; it also hooks up the
	 * {@link org.eclipse.emf.edit.provider.INotifyChangedListener}.
	 */
	public void setDecoratedItemProvider(
			INotifier<INotification> decoratedItemProvider) {
		if (this.decoratedItemProvider != null) {
			this.decoratedItemProvider.removeListener(this);
		}

		this.decoratedItemProvider = decoratedItemProvider;

		if (decoratedItemProvider != null) {
			decoratedItemProvider.addListener(this);
		}
	}

	@Override
	public String toString() {
		return getClass().getName() + '@' + Integer.toHexString(hashCode());
	}

}