Bug 261506 [CommonNavigator] NavigatorDNDService seems like it can use only interfaces
The NavigatorDNDService class seems like it could use only interface APIs and function properly. Patch attached.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/dnd/NavigatorDnDService.java
package org.eclipse.ui.internal.navigator.dnd;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Map;
import java.util.Set;
import org.eclipse.jface.util.LocalSelectionTransfer;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.swt.dnd.TransferData;
import org.eclipse.ui.internal.navigator.NavigatorContentService;
import org.eclipse.ui.internal.navigator.extensions.CommonDragAssistantDescriptor;
import org.eclipse.ui.internal.navigator.extensions.NavigatorViewerDescriptor;
import org.eclipse.ui.navigator.CommonDragAdapterAssistant;
import org.eclipse.ui.navigator.CommonDropAdapterAssistant;
import org.eclipse.ui.navigator.INavigatorContentService;
import org.eclipse.ui.navigator.INavigatorDnDService;
/**
 * 
 * Provides instances of {@link CommonDragAdapterAssistant} and
 * {@link CommonDropAdapterAssistant} for the associated
 * {@link INavigatorContentService}.
 * 
 * <p>
 * Clients may not extend, instantiate or directly reference this class.
 * </p>
 * 
 * @since 3.2
 * 
 */
public class NavigatorDnDService implements INavigatorDnDService {