Bug 21631 JavaUI.createTypeDialog() should provide default message [dialogs]
2.0 Release If you use JavaUI.createTypeDialog() to create a new (single selection) type dialog, and then open the dialog, the open will fail silently. The dialog cannot be succesfully opened unless you send setMessage() to the dialog before you open it. This behaviour should be documented, or, preferably, a default message ("Please select a type/class/interface") should be provided.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/JavaUI.java
/** 
	 * Reveals the given java element  in the given editor. If the element is not an instance
	 * of <code>ISourceReference</code> this method result in a NOP. If it is a source
	 * reference no checking is done if the editor displays a compilation unit or class file that 
	 * contains the source reference element. The editor simply reveals the source range 
	 * denoted by the given element.
	 * 
	 * @param part the editor displaying a compilation unit or class file
	 * @param element the element to be revealed
	 * 
	 * @since 2.0
	 */
	public static void revealInEditor(IEditorPart part, IJavaElement element) {
		EditorUtility.revealInEditor(part, element);
	}
	 
	/**
	 * Returns the working copy manager for the Java UI plug-in.
	 *
	 * @return the working copy manager for the Java UI plug-in
	 */
	public static IWorkingCopyManager getWorkingCopyManager() {
		return JavaPlugin.getDefault().getWorkingCopyManager();
	}
	
	/**
	 * Answers the shared working copies currently registered for the Java plug-in. 
	 * 
	 * @return the list of shared working copies this plug-in