Bug 81329 Disable sort member action for enums
Tobias, can you please disable the sort member action for enums. JDT/Core can't fix the problem.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/SortMembersAction.java
}	
	
	/* (non-Javadoc)
	 * Method declared on SelectionDispatchAction
	 */
	public void run(IStructuredSelection selection) {
		Shell shell= getShell();
		try {
			ICompilationUnit cu= getSelectedCompilationUnit(selection);
			int cuMembers= cu.getTypes().length;
			
			IType type= cu.findPrimaryType();
			int memberCount= type.getChildren().length;
			if (cuMembers <= 1 && memberCount <= 1) {
				MessageDialog.openInformation(getShell(), getDialogTitle(), ActionMessages.getString("SortMembersAction.no_members")); 			
				return;
			}
			
			if (cu == null || !ElementValidator.check(cu, getShell(), getDialogTitle(), false)) {
				return;
			}
			
			
			IEditorPart editor= EditorUtility.openInEditor(cu);
			if (editor != null) {
				run(shell, cu, editor);
			}
		} catch (CoreException e) {
			ExceptionHandler.handle(e, shell, getDialogTitle(), null); 
		}