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How to send Integer value in the form of JSON format and recieve in REST Controller?

I have one REST Controller where I have written this code
#PostMapping(value = "/otp")
public void otp(#RequestBody Integer mobile) {
System.out.println(" Mobile = "+mobile);
}
And I am calling this method from Postman with the following inputs
URL : localhost:8080/otp
Body :
{
"mobile":123456
}
But I am getting the following exception
org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Can not deserialize instance of java.lang.Integer out of START_OBJECT token; nested exception is com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.lang.Integer out of START_OBJECT token
If I am taking String as a parameter like this
#PostMapping(value = "/otp")
public void otp(#RequestBody String mobile) {
System.out.println(" Mobile = "+mobile);
}
And passing the inputs as
{
"mobile":123456
}
Now it is printing in the console as follows
Mobile = {
"mobile":"123456"
}
But I want only this value 123456. How to achieve my requirement?
NOTE: I don't want to create any additional POJO class or even I don't want to send the data using query/path parameter.

If you want to send your body like:
{
"mobile":123456
}
You will create another object to receive the value.
But if you only want to accept the integer value without any other object, you will not put json object in request body, but only the integer itself.
Body:
12345

You can use a class as request body:
class Request {
public Integer mobile;
}
and specify the parameter like this:
public void otp(#RequestBody Request mobile) {
...

Create a pojo class like below.
public class Mobile{
private Integer mobile;
//getter and setter
}
And then
public void otp(#RequestBody Mobile mobile)
to print value use
mobile.getMobile();

Converting process with json and #RequestBody is automatically and need you provide a class which contains proper field.If you insist to send data by request body,you could use String to receive json data as String.For example:
public void test(#RequestBody String request){
log.info(request);
}
In this way the request body you received is a String.You need some other tool to help you convert it.Like org.json,you could get more info from here HttpServletRequest get JSON POST data
But the easiest way is creating a new class to receive the data or changing #RequestBody to #RequestParam or #Pathvariable.
If you still want to use json as the request body,maybe you could create a common class A which contain lots of fields like name,phone number,email...Then after you send a request which only contains mobile,you just need to A.getMobile().In this way, even you get 100 request,you still need one POJO(but not recommend)

Just send the number in JSON.
12345
use #RequestBody to receive the int number.
it will work.
I use postman to send it in RAW JSON.
BTW, I am a beginner learning Spring Boot.

if you have org.json.JSONObject
#PostMapping(value = "/otp")
public void otp(#RequestBody String mobile) {
JSONObject obj = new JSONObejct(mobile);
System.out.print(obj.getInt("mobile"));
}

How to create generic json response Object in java?

I am new to java and creating some Restful services in netbeans using jersey framework.
I have created many GET, POST web services which is having different different type of responses which are basically Model Objects and depending upon media type I am getting JSON or XML.
Some response is having only a single object which is being shown in JSON inside {}, and some are list which are in [].
I want to see a generic response format for all api responses.
Example-
{"status":"0 or 1", "message":"any string message","result":"it can be a single object or a list of objects which is dynamic depending upon each web service response"}.
Since here in java we need to created model objects for getting responses so I have created a ResponseModel which is having a status property , message property but don't know the type of result property because sometime it can have a single object or sometime a list so what type should I set for this property so that I can assign any thing to this and response will always be in same format for JSON or XML.
I have created a static method with constructor which takes all these three parameters and create a ResponseModel object.
Thanks in advance
EDITED- Code after Using "Object" as generic type
public static Response getResponseObjectIsValid(boolean isValid, String message,Object result)
{
if (isValid == true) {
LGSResponse response = new LGSResponse();
response.setStatus(1);
response.setMessage(message.length()>0 ? message : "Success");
response.setResult(result);
return Response.status(Status.OK).entity(response).build();
}
else
{
LGSResponse response = new LGSResponse();
response.setStatus(1);
response.setMessage(message.length()>0 ? message : "Failed");
response.setResult(result);
return Response.status(Status.OK).entity(response).build();
}
}
Result Parameter is a normal model object.

You can simply create your class as you've said.
public class ResponseModel {
int status;
String message;
Object result;
// contructor, getters, setters go here...
// (probably consider using lombok, but that is a story for another time)
}
Then you can pass either a single object or an array as the 3rd param and the json/xml serializer should take care of the conversion for you unless your objects are very complex(I rarely run into that problem)
For example, your Jersey methods would look something like this:
// returning a single object within the response model
#GET
#Path("/myMethod")
public Response aJerseyMethod() {
Book aBookObject = new Book("The Title", "Name of Author");
ResponseModel responseModel = new ResponseModel(1, "This is a book", aBookObject);
return Response.ok(responseModel)
.build();
}
// returning an array within the response model
#GET
#Path("/myOtherMethod")
public Response anotherJerseyMethod() {
Book aBookObject = new Book("The Title", "Name of Author");
Book anotherBookObject = new Book("The Other Title", "Name of another Author");
ArrayList<Book> aBookArray = new Arraylist();
aBookArray.add(aBookObject);
aBookArray.add(anotherBookObject);
ResponseModel responseModel = new ResponseModel(1, "These are books", aBookArray);
return Response.ok(responseModel)
.build();
}
In both cases you should get the expected output you were talking about and you do not have to do any additional checks or conversions yourself.
I just wrote this here, so try it out with your own classes instead of "Book" (which is not a real class) and let me know if it works.

You should not maintains status code, message and result within json body.
Response message should only contain the result of that api.
Httpstatus code will be the status code (Ex.200 is success, 404 is notfound)
All the other info should be maintained in response headers, not within json body

Cannot get JSON data from Jersey GET response

I was developing a restful web client and trying to get the JSON payload from the response of a GET method. I am using Jersey. But I just cannot read the JSON data using response.getEntity() method. I tried many methods including response.bufferEntity(), but the output always kept empty. Below is my code and output, and in addition I can see the JSON data right in the response packet captured in wireshark. I would really appreciate everyone trying to help figure out why or provide solution. Thank you!
Code:
public JSONObject Get(String requestPath){
ClientResponse response = webResource.path(requestPath)
.header("Content-Type", contTypeHeader )
.header("Accept",acceptHeader)
.header("Authorization", authZ )
.get(ClientResponse.class);
response.bufferEntity();
if (!(response.getStatus() == 201 || response.getStatus() == 200)) {
throw new RuntimeException("Failed : HTTP error code : " + response.getStatus());
}
System.out.println(response.getEntity(JSONObject.class));
return null;
}
and the output is always like this: {}

You can't use JSONObject unless you have a MessageBodyReader for it. See more at JAX-RS Entity Providers. The provider you are currently using (probably Jackson) only supports JavaBean POJOs or collections of them. For example if you have this JSON
{ "property1" : "value1", "property2": "value2" }
Then you would need to have a POJO like
public class Bean {
private String property1;
private String property2;
// getters and setters
}
Then you can do getEntity(Bean.class). The reason you are getting an empty object, is that the deserialization works off the setters. It looks for properties on the JSON, that matches a setters, and uses it the set the property. The JSON object has no setters for your JSON properties.

Returning model object from Controller to Ajax jquery not working in Spring mvc

I am trying to return a model object from spring mvc controller back to jquery ajax method but it is returning blank as the response
jsp:
$( "#dialog-link10" ).click(function( event ) {
var appname= $("#dialog-link10").text();
alert(appname);
if(appname == 'RS Applications') {
$.ajax({
type : "GET",
url : 'abc.html',
dataType: 'JSON' ,
data:
{"id" : $("#dialog-link10").text()}
,
success : function(data) {
alert('success')
alert('data')
}
});}
controller:
#RequestMapping(method=RequestMethod.GET, value="/abc")
#ResponseBody
public Model helloWorld2( #RequestParam("id") String id, Model model) {
System.out.println("*****"+id);
List <String> list1=new ArrayList<String>();
List <String> list2=new ArrayList<String>();
System.out.println("here");
list1.add("abc");
list1.add("abc2");
list1.add("abc3");
list1.add("abc4");
model.addAttribute("list1", list1);
return model;
}
This is not generating success alert as well.
Please suggest

Your method should return directly the list, as a json, no need to put it in the model and return the model. Also check if you have an error in your callback ajax.

You are specifying dataType: 'JSON' in your ajax call, but you are not converting your response object (model) to json in your controller.
From the jQuery ajax documentation for dataType setting:
The type of data that you're expecting back from the server. If none is specified, jQuery will try to infer it based on the MIME type of the response (an XML MIME type will yield XML, in 1.4 JSON will yield a JavaScript object, in 1.4 script will execute the script, and anything else will be returned as a string)
You'll probably want to reference a json serializer (unless you want to write your own) - but the important part is serializing your model to json in your response. For example (using json-io):
String jsonModel = JsonWriter.objectToJson(model);
return jsonModel;
You can then access the string array contained in your json response object in the following way:
success : function(data) {
for (i = 0; i < data.list1.length; i++){
alert(data.list1[i]);
}
}
And a fiddle example for reading json objects

I met this problem and it took me several hours to find out the problem.
Just remove "Model model" from your parameter.
Use a Map<String, String> or Map<String, Object> instead.

Try adding the produces = MediaType.APPLICATION_JSON to the RequestMapping annotation
#RequestMapping(method=RequestMethod.GET, value="/abc", produces = MediaType.APPLICATION_JSON)
Also, you may not need the Model paramater in the method.

json and Spring MVC

I have trouble with Spring MVC and json.
I use SimplecartJS to generate json data like this :
{"currency":"RUR",
"shipping":250,
"tax":0,
"taxRate":0,
"itemCount":2,
"item_name_1":"Name of product #1",
"item_quantity_1":6,
"item_price_1":159,
"item_options_1":"",
"item_name_2":"Name of product #2",
"item_quantity_2":2,
"item_price_2":159,
"item_options_2":"",
"form":{
"Fname":"UserName",
"Phone":"7123456789",
"Address":"UserAddress",
"Comment":"Comment Text"
}
}
My controller Spring
#RequestMapping(value = "/checkorder2", method = RequestMethod.POST, headers = "Accept=application/json")
public String test (#RequestBody OrderCon orderC)throws Exception{
ObjectMapper om = new ObjectMapper();
om.canSerialize(OrderCon.class);
System.out.println(om);
return test(orderC);
}
Code from client side
var url = 'http://localhost:8080/url'
jQuery.ajax({
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json'
},
contentType:'application/json',
dataType: "json",
type: "POST",
url: url,
data: JSON.stringify(data),
And my question:
When I send data to controller, I have a mistake 400 Bad request. The request sent by the client was syntactically incorrect. When adding a new item field name will "item_name_2","item_name_3" etc. How I can parse this. I try parse to List, Set but it is not working. Please help.
UPD1: OrderCon.java
public class OrderCon {
private List<String> form;
private List<List<String>> json;
getters and setters...
}

There is no way you are going to be able to parse that data to a class like you have, since you need to add dynamic properties to a Java class.
You do however have two options to get the data out
First option is parse the json to a HasMap of Strings, ie. change your controller signature to
public String test (#RequestBody Map<String, String> orderC)
The other option is to use a JsonNode and deal with the data as a tree, here is an example http://wiki.fasterxml.com/JacksonTreeModel
I personally would try the latter first

You're getting 400 Bad Request because Spring is trying to map the passed JSON directly to your OrderCon class.
For this to work, the class would need to map to the keys specified in the JSON.
IE:
JSON:
{
"name" : "foo",
"phone": "111-111-1111"
}
would map to:
public class someJsonPojo(){
String name;
String phone;
//setters & getters
}
I don't think this will work well since instead of getting an array of items, you only get an item appended to the list as a new key:value. You should be able to modify the JSON so that you can map to an array of Item objects, which contain the name, quantity, price, etc.