1. A computer-implemented method of generating mainframe computer code, the method comprising: (a) receiving the identification of at least one input and output operation; (b) retrieving at least one code segment from a collection of input and output operation code segments to perform the at least one input and output operation; (c) retrieving at least one code segment from a collection of error handling operation code segments to perform at least one error handling operation associated with the at least one input and output operation; and (d) generating a mainframe computer code template that includes the code segments retrieved in (b) and (c).