code: protected GraphQLFieldDefinition getFieldDef(ExecutionContext executionContext, ExecutionStrategyParameters parameters, Field field) {
          GraphQLObjectType parentType = (GraphQLObjectType) parameters.getExecutionStepInfo().getUnwrappedNonNullType();
          return getFieldDef(executionContext.getGraphQLSchema(), parentType, field);
      }
docs: Called to discover the field definition give the current parameters and the AST {@link Field}
  
  @param executionContext contains the top level execution parameters
  @param parameters       contains the parameters holding the fields to be executed and source object
  @param field            the field to find the definition of
  
  @return a {@link GraphQLFieldDefinition}