What are the best way to GET Data from UI to the Web Controller in Java?

[varun neema]

The possible ways are as below but need inputs on best practices as well some samples :
1) @RequestParam Map<String, String>
2) @RequestBody String

[E Armitage]

Are those annotations from some framework you are using? If so then you need to find starter tutorials for that framework and read them including examples they have.
If you are using a framework then say which one so this thread gets moved to the right sub-forum (your question has nothing to do with Object Relational Mapping)

[Richard Chesterwood]

Sounds like SpringMVC? If so it sounds like you should concentrate on using RequestParam for now:

eg

@RequestMapping("/findByAuthor")
public ModelAndView findByAuthor(@RequestParam("AUTHOR") String author)
{
	List<Book> books = bookService.getAllBooksByAuthor(author);
	return new ModelAndView("displayAllBooks", "allBooks", books);
}

RequestBody is used for handling the entire request body, for example if you want to handle a PUT request sending something more complex than a parameter. An example of its use here: http://www.beabetterdeveloper.com/2013/07/spring-mvc-requestbody-and-responsebody.html

[varun neema]

Thanks Richard and E Armitage for the inputs. Let me provide some more details -
I want to search for a Domain object name Contract with different parameters. For now I search for five parameters: FromDate, EndDate, Season, Name and Category. In future it should be possible to search for dynamic way of parameters. All the parameters are values of contract domain object.

var contract= {fromDate:moment($('#datepickerVon').val(), 'DD-MM-YYYY').format('DD-MM-YYYY'),
           endDate:moment($('#datepickerBis').val(), 'DD-MM-YYYY').format('DD-MM-YYYY'),
           season:$('#season').val(),
           name:$('#name').val(),
           category:$('#category').val()};

      $.ajax({
          url:'/contract/search/',
          dataType: "json",
          type: "GET",
          traditional : true,
          contentType: "application/json",
          data: contract,
          success: function(data) {

          }
          });

I used this controller method

 @RequestMapping(value = "/search/", method = RequestMethod.GET, headers = "Accept=application/json")
@ResponseBody
public ResponseEntity<String> getContractFromSearch(
        @RequestParam Map<String, String> allRequestParams, ModelMap model) {List<Vertrag> result = Contract.findAllContractsPerParameter(
            allRequestParams.get("fromDate"),
            allRequestParams.get("endDate"),
            Season.findSeason(allRequestParams.get("season").toUpperCase()),
            Name.findName(allRequestParams.get("name").toUpperCase()),
            Category.findCategory(allRequestParams.get("category").toUpperCase()));
    HttpHeaders headers = new HttpHeaders();
    headers.add("Content-Type", "application/json; charset=utf-8");
    return new ResponseEntity<String>(Contract.toJsonArray(result), headers,
            HttpStatus.OK);
}

Season, Name, Category are dependencies of Contract. So for the jpa query I need the full Object of each. For this I want a dynamical way instead of writing similar code for all. But I'm quite sure that there is another and better solution. May be it is possible to do it with the contract object (domain and json) itstelf and also the jpa query.

Thanks for your inputs.