Bug 38496 sort members: should be disabled on types with no members [code manipulation]
20030604 currently what you get is a no-op. not even an info dialog
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/SortMembersAction.java
private CompilationUnitEditor fEditor;
	/**
	 * Creates a new <code>SortMembersAction</code>. The action requires
	 * that the selection provided by the site's selection provider is of type <code>
	 * org.eclipse.jface.viewers.IStructuredSelection</code>.
	 * 
	 * @param site the site providing context information for this action
	 */
	public SortMembersAction(IWorkbenchSite site) {
		super(site);
		setText(ActionMessages.getString("SortMembersAction.label")); 
		setDescription(ActionMessages.getString("SortMembersAction.description")); 
		setToolTipText(ActionMessages.getString("SortMembersAction.tooltip")); 		
		
		WorkbenchHelp.setHelp(this, IJavaHelpContextIds.SORT_MEMBERS_ACTION);
	}
	/**
	 * Note: This constructor is for internal use only. Clients should not call this constructor.
	 */
	public SortMembersAction(CompilationUnitEditor editor) {
		this(editor.getEditorSite());
		fEditor= editor;
		setEnabled(checkEnabledEditor());
	}
	
	private boolean checkEnabledEditor() {
		return fEditor != null && SelectionConverter.canOperateOn(fEditor);