[Spring] Abstract Wizard Form Controller

[Vikas Kapoor]

I have three pages. If user ticks one checkbox (please tick this if your billing address is same as company address) on the first page then on the third page the information related to billing address should be filled automatically when page gets loaded.
In which abstract wizard form controller method I should write the logic?

protected Map referenceData(HttpServletRequest request, int page)throws Exception

Is referenceData method appropriate for this?

or

protected void postProcessPage(HttpServletRequest request, Object command,
Errors errors, int page) throws Exception {

as I require command object to set the values?

I have asked the same question here.