Convert Java complex objects to JSON

I need to convert the following classes:

package comS309.traxz.data;

import java.util.Collection;

import org.json.JSONException;
import org.json.JSONObject;

public class ExerciseSession {

    public String DateCreated;
    public String TotalTime;
    public String CaloriesBurned;
    public String AvgSpeed;
    public String SessionName;
    public String Distance;
    public String SessionType;
    public String UserId;
    public Collection<LatLon> LatLons;
}

Latlon is as follows:

public class LatLon {

    public String LatLonId;
    public String Latitude;
    public String Longitude;
    public String ExerciseSessionId;
    public String LLAveSpeed;
    public String Distance;
}

So class exercisesession has a set of latlon objects Now I need to convert the exercisesession class from Java to JSON format and send it to my server

I do this on the Android operating system if it's important

My current solution is:

JSONObject ExerciseSessionJSOBJ = new JSONObject();
ExerciseSessionJSOBJ.put("DateCreated",this.DateCreated);
            ExerciseSessionJSOBJ.put("TotalTime",this.TotalTime);
            ExerciseSessionJSOBJ.put("CaloriesBurned",this.CaloriesBurned);
            ExerciseSessionJSOBJ.put("AvgSpeed",this.AvgSpeed);
            ExerciseSessionJSOBJ.put("SessionName",this.SessionName);
            ExerciseSessionJSOBJ.put("Distance",this.Distance);
            ExerciseSessionJSOBJ.put("SessionType",this.SessionType);
            ExerciseSessionJSOBJ.put("UserId",this.UserId);
            //add the collection
            for(LatLon l: LatLons)
            {
                ExerciseSessionJSOBJ.accumulate("LatLons",l);
            }

I'm not sure if it works I'm new to Jason and need help Thank you for your help!

Solution

It's easy to use Google's gson library This is an example:

Gson gson = new Gson();
String jsonRepresentation = gson.toJson(myComplexObject);

And get the object:

Gson gson = new Gson();
MyComplexObject myComplexObject = gson.fromJson(jsonRepresentation,MyComplexObject.class);

http://code.google.com/p/google-gson/