Abstract: During a period for which a UI realized by a screen control program is presented and requirements are determined in a development period of application, a managed bean provided with only a collective storage area in which variables are stored as a variable storage area is used to and prototype script for performing a pseudo-processing and the screen control program work with to realize the presentation of the UI. When the variables transmitted between the programs are established, a web service providing program is developed and the web service providing program replaces the prototype script, and the managed bean is replaced by a new managed bean to which an individual storage area provided for each variable transmitted to and from the web service providing program and a program which copies the variable between the collective storage area and the individual storage area are added.