JSON Parameter for Web Service

Question

I am trying to create a web service which will taken in JSON response and then query the DB with it to return store details (JSON response).

I intend to use this with a mobile app later on. But during the development I am testing using AJAX calls. I am using a @GET request at the moment. I was able to successfully return a JSON response. I am now facing a problem with passing the JSON Object to the @GET method. On debugging, I see that there is a null value in my input parameter. Can somebody take a look at my code and advise what I am doing wrong?

import javax.ws.rs.core.Context;
import javax.ws.rs.core.UriInfo;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PUT;

import java.util.Iterator;

import org.json.simple.JSONObject;
import org.json.simple.JSONArray;
import org.json.simple.JSONValue;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;

/**
 * REST Web Service
 *
 * @author Aj
 *
 * This service will return the offers valid for the IMSI number passed
*/
@Path("getOffers")
public class GetOffersResource {

    @Context
    private UriInfo context;

    /**
    * Creates a new instance of GetOffersResource
     */
    public GetOffersResource() {
    }

    @GET
    @Consumes("application/json")
    @Produces("application/json")
    public String getJson(final String input) {

        JSONParser parser = new JSONParser();
        String[] response = new String[5];

        try {
            Object obj = parser.parse(input);
            JSONObject jsonObject = (JSONObject) obj;
            offerProcess ofc = new offerProcess();
            ofc.setLatitude((double) jsonObject.get("latitude"));
            ofc.setLongitude((double) jsonObject.get("longitude"));
            ofc.setIMSI((long) jsonObject.get("IMSI"));

            response = ofc.fetchOffers();

        } catch (ParseException e) {
            JSONObject ser = new JSONObject();

            ser.put("status", "error");
            ser.put("reason", "Bad request");

            return ser.toJSONString();
        }

        //TODO return proper representation object
        JSONObject ser = new JSONObject();
        JSONArray arr = new JSONArray();

        arr.add("456TYU");
        arr.add("OLED TV");
        arr.add("24-JUL-2014");
        arr.add("XYZ Enterprises");
        arr.add("Gachibowli");
        arr.add("9911278366");

        ser.put("status", "success");
        ser.put("Offers", arr);

        System.out.println(ser);

        return ser.toJSONString();
    }

    /**
     * PUT method for updating or creating an instance of GetOffersResource
     *
     * @param content representation for the resource
     * @return an HTTP response with content of the updated or created resource.
     */
    @PUT
    @Consumes("application/json")
    public void putJson(String content) {
    }
}

Here is the offerProcess class -

public class offerProcess {

    private double longitude;
    private double latitude;
    private long IMSI;

    public double getLongitude() {
        return longitude;
    }

    public double getLatitude() {
        return latitude;
    }

    public void setLongitude(double longitude) {
        this.longitude = longitude;
    }

    public void setLatitude(double latitude) {
        this.latitude = latitude;
    }

    public long getIMSI() {
        return IMSI;
    }

    public void setIMSI(long IMSI) {
        this.IMSI = IMSI;
    }

    public String[] fetchOffers(){
        String[] response = new String[5];

        response[0] = "456TYU";
        response[1] = "OLED TV";
        response[2] = "24-JUL-2014";
        response[3] = "XYZ Enterprises";
        response[4] = "Gachibowli";
        response[5] = "9980556990";

        return response;
    }
}

For what it's worth, I am using the JSON.Simple library.

Answer 1

Assuming your input paramter is a query parameter for the GET request, then you need to add @QueryParam annotation to the parameter:

    @GET
    @Consumes("application/json")
    @Produces("application/json")
    public String getJson(@QueryParam("input") final String input) {
          ...
    }

Edit:

However, like @troylshields mentioned, if you are attempting to send a JSON object, you must use POST or PUT (depending on the circumstances). GET request only support query parameter, and trying to send a JSON string via a query parameter is not a good idea.