docs: @Override
      public void handle(CommandContext ctx) throws CommandLineException {
  
          ModelControllerClient client = ctx.getModelControllerClient();
          if(client == null) {
              throw new CommandFormatException("You are disconnected at the moment." +
                      " Type 'connect' to connect to the server" +
                      " or 'help' for the list of supported commands.");
          }
          RequestWithAttachments reqWithAttachments
                  = (RequestWithAttachments) ctx.get(Scope.REQUEST, "OP_REQ");
          if (reqWithAttachments == null) {
              throw new CommandLineException("Parsed request isn't available.");
          }
          ModelNode request = reqWithAttachments.getRequest();
          OperationBuilder opBuilder = new OperationBuilder(request, true);
          for (String path : reqWithAttachments.getAttachedFiles()) {
              opBuilder.addFileAsAttachment(new File(path));
          }
          Operation op = opBuilder.build();
  
          if(ctx.getConfig().isValidateOperationRequests()) {
              ModelNode opDescOutcome = Util.validateRequest(ctx, request);
              if (opDescOutcome != null) { // operation has params that might need to be replaced
                  Util.replaceFilePathsWithBytes(request, opDescOutcome);
              }
          }
  
          try {
              final ModelNode result = ctx.execute(op, "Operation request");
              if (Util.isSuccess(result)) {
                  ctx.printDMR(result);
              } else {
                  throw new CommandLineException(result.toString());
              }
          } catch(NoSuchElementException e) {
              throw new CommandLineException("ModelNode request is incomplete", e);
          } catch (CancellationException e) {
              throw new CommandLineException("The result couldn't be retrieved (perhaps the task was cancelled", e);
          } catch (IOException e) {
              if (e.getCause() != null && !(e.getCause() instanceof InterruptedException)) {
                  ctx.disconnectController();
              }
              throw new CommandLineException("Communication error", e);
          } catch (RuntimeException e) {
              throw new CommandLineException("Failed to execute operation.", e);
          }
      }