Parse request JSON in Spring REST controller called from jQuery ajax

Question

I'm building a HTML form which upon submit, calls a REST api and sends the form values in JSON.

Like this:

Rest call:

var url = "http://localhost:8080/backend";
$.ajax({
    url: url,
    type: 'post',
    data: requestJson,
    success: function( data, textStatus, jQxhr ){
        console.log(data);
    },
    error: function( jqXhr, textStatus, errorThrown ){
        console.log( errorThrown );
    }
});

Example JSON:

{
  "id": "1",
  "domain": "planes",
  "types": [
    "military",
    "commercial"
  ],
  "details": [
    {
      "military": {
        "name": "f18",
        "country": "US"
      }
    },
    {
      "commercial": {
        "name": "a380",
        "country": "Finland"
      }
    }
  ]
}

On backend, I'm running a spring-boot application which accepts this JSON as request and performs some operations.

class MyRequestDTO {
    @JsonProperty("type")
    private String type;

    @JsonProperty("domain")
    private String domain;

    @JsonProperty("types")
    private String[] types;

    ......
}

REST call in Controller

@RequestMapping(value = "/save", method = RequestMethod.POST, consumes = MediaType.APPLICATION_FORM_URLENCODED_VALUE)
public Map<String, List<String>> createSot(@Valid MyRequestDTO myRequestDTO) {

    System.out.println(sotDTO.getId());         //THIS WORKS
    System.out.println(sotDTO.getDomain());     //THIS WORKS
    String[] types = sotDTO.getTypes();         //THIS DOES NOT WORK
    for(String e: types) {
        System.out.println("type: " + e);
    }

}

Issue is I'm not able to get types array & it is throwing null exception.

Any suggestions what I need to change.

Thanks

Answer 1

Change private String[] types; to private List<String> types; would help.

Plus, as you mentioned you're using spring-boot as backend service, so you don't really need @JsonProperty annotation at all. Remove them to make less code.