How to convert a Java Object to a JSONObject?

Question

i need to convert a POJO to a JSONObject (org.json.JSONObject)

I know how to convert it to a file:

    ObjectMapper mapper = new ObjectMapper();     try {         mapper.writeValue(new File(file.toString()), registrationData);     } catch (JsonGenerationException e) {         e.printStackTrace();     } catch (JsonMappingException e) {         e.printStackTrace();     } catch (IOException e) {         e.printStackTrace();     } 

But I dont want a file this time.

Answer 1

If we are parsing all model classes of server in GSON format then this is a best way to convert java object to JSONObject.In below code SampleObject is a java object which gets converted to the JSONObject.

SampleObject mSampleObject = new SampleObject(); String jsonInString = new Gson().toJson(mSampleObject); JSONObject mJSONObject = new JSONObject(jsonInString); 

Answer 2

If it's not a too complex object, you can do it yourself, without any libraries. Here is an example how:

public class DemoObject {      private int mSomeInt;     private String mSomeString;      public DemoObject(int i, String s) {          mSomeInt = i;         mSomeString = s;     }      //... other stuff      public JSONObject toJSON() {          JSONObject jo = new JSONObject();         jo.put("integer", mSomeInt);         jo.put("string", mSomeString);          return jo;     } } 

In code:

DemoObject demo = new DemoObject(10, "string"); JSONObject jo = demo.toJSON(); 

Of course you can also use Google Gson for more complex stuff and a less cumbersome implementation if you don't mind the extra dependency.