Combine GET and POST request methods in Spring

@RequestMapping(value = "/testonly", method = { RequestMethod.GET, RequestMethod.POST })
public ModelAndView listBooksPOST(@ModelAttribute("booksFilter") BooksFilter filter,
        @RequestParam(required = false) String parameter1,
        @RequestParam(required = false) String parameter2, 
        BindingResult result, HttpServletRequest request) 
        throws ParseException {

    LONG CODE and SAME LONG CODE with a minor difference
}

if @RequestParam(required = true) then you must pass parameter1,parameter2

Use BindingResult and request them based on your conditions.

The Other way

@RequestMapping(value = "/books", method = RequestMethod.GET)
public ModelAndView listBooks(@ModelAttribute("booksFilter") BooksFilter filter,  
    two @RequestParam parameters, HttpServletRequest request) throws ParseException {

    myMethod();

}


@RequestMapping(value = "/books", method = RequestMethod.POST)
public ModelAndView listBooksPOST(@ModelAttribute("booksFilter") BooksFilter filter, 
        BindingResult result) throws ParseException {

    myMethod();

    do here your minor difference
}

private returntype myMethod(){
    LONG CODE
}