Spring控制器的工作方式与GET和POST方法类似

Question

I have a method like below in my Spring application

@RequestMapping(value = "/search-result-doctors", method = RequestMethod.POST)
public String getDoctorSearchResults(String LastName, String Hospital, String Specialty, String date1, ModelMap model) {
    //some logics

     return "doctorchannelling/search-result-doctors";
}

after going in to the page "search-result-doctors" when I press the just Enter in the URL it has to remain in the same page. Since it is a GET request I have written the same method again with a method value RequestMethod.GET.

@RequestMapping(value = "/search-result-doctors", method = RequestMethod.GET)
public String getDoctorSearchResults(String LastName, String Hospital, String Specialty, String date1, ModelMap model) {
    //some logics

    return "doctorchannelling/search-result-doctors";
}

due to the unavailability of parameter values String LastName, String Hospital, String Specialty, String date1 in the GET request i'm getting a Exception

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException

How can I resolve this problem

Thanks in advance

Answer 1

Actually you can define just one method to process both GET and POST

@RequestMapping(value = "/search-result-doctors", method = { RequestMethod.POST, RequestMethod.GET })

If you get NPE somewhere in your some logic just check which parameters are empty.

Answer 2

In addition to what @StanislavL is saying, you should annotate your parameters with @RequestParam(required=false) , so

public String getDoctorSearchResults(@RequestParam(required=false) String LastName,@RequestParam(required=false) String Hospital, @RequestParam(required=false) String Specialty, @RequestParam(required=false) String date1, ModelMap model) {

combined with the method annotation and NullPointer checkes as given by @StanislavL, should give you what you want