code: public ResultHandlerContext<DPO, RI, RO, Collection<RO>> handleWith(ResultHandler<Collection<RO>> resultHandler) {
          List<ResultHandler<Collection<RO>>> addedResultHandlers = new ArrayList<ResultHandler<Collection<RO>>>();
          if (resultHandler != null) {
              addedResultHandlers.add(resultHandler);
          }
  
          // Change context
          return new ResultHandlerContext<DPO, RI, RO, Collection<RO>>(addedTriggers, addedDataProviders,
                  dataProviderToRuleMapping, addedRuleInputTransformers, addedRules,
                  GeneralValidator.MappingStrategy.JOIN, null, addedResultHandlers);
      }
docs: Adds the specified result handler to the validator under construction.
  
  @param resultHandler Result handler to be added.
  
  @return Context allowing further construction of the validator using the DSL.