how to convert nested json data into pojo in spring?

[shivmaruti singh]

I got json data from api like {"id":"{"$id" : "126geto89900ok650"},
"student_rollno" : "1234567",
"student_answers": [{"1" :"5"}, {"2" : "5"},{"3","4"}],
"mother_answer": " " }


how can I convert this json data to pojo . I can do simple json data conversion. And also how to check weather incoming values are empty or not like mother variable is empty sp please suggest me how to do that ?

[Partheban Udayakumar]

shivmaruti singh,

Is this an API response? If so can you show us how you tried to get this response to you controller?

[shivmaruti singh]

yes this is Api response . i used

ObjectMapper objectMapper = new ObjectMapper();
		
		
		try {
			ReportComingValues value=objectMapper.readValue(new URL(uri),ReportComingValues.class);
		
			
		} catch (JsonParseException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (JsonMappingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

where uri is API url.

[Winston Gutkowski]

shivmaruti singh wrote:yes this is Api response . i used...

Just as an aside, I'm not wild about those auto-generated catch blocks. Why not:
  throw new Error(e);
instead?

It's nothing to do with you, but as it stands that code would just spew out a stacktrace every time it got an error, and merrily continue processing - and you might never know that it had a problem until you ended up with a NullPointerException.

Winston

[shivmaruti singh]

anyone can suggest me how to convert given json into pojo in controller please its urgent.

[Partheban Udayakumar]

shivmaruti singh,

You can use something like Map<String, object> to handle this. Can you show us your ReportComingValues class?

shivmaruti singh wrote:anyone can suggest me how to convert given json into pojo in controller please its urgent.

People answering here are from different time zones, so please be patient

[shivmaruti singh]

Thanks for reply.
I know people works from different timezone. but actually My project have stopped just for conversion of json to pojo.

public class ReportComingValues {
private Map  <String ,String>id;
	private long student_rollno;
	private Map<String , Integer>student_answer;
	private Map<String, Integer>father_answer;
	private Map<String,Integer>mother_answer;

//getter and setter	
}

but it not work it is showing exception.

INFO: Server startup in 3923 ms
com.fasterxml.jackson.databind.JsonMappingException: Can not instantiate value of type [map type; class java.util.LinkedHashMap, [simple type, class java.lang.String] -> [simple type, class java.lang.Integer]] from String value (''); no single-String constructor/factory method
 at [Source: http://url] (through reference chain: com.careerco.aakashphase2stresseport.model.ReportComingValues["mother_answer"])

[Partheban Udayakumar]

shivmaruti singh wrote: {"id":"{"$id" : "126geto89900ok650"},
"student_rollno" : "1234567",
"student_answers": [{"1" :"5"}, {"2" : "5"},{"3","4"}],
"mother_answer": " " }

This response is not of the type Map<String, Integer> its actually of the type Map<String, Object>

[shivmaruti singh]

anyone can please suggest me that what will be the suitable pojo structure for this given json . I tried much but did not solve .