How to read json payload in restful webservice java

Question

I am trying to read json payload in restful webservice in java. But I am not sure how to do. I researched a lot but was not able to find something useful. can some one help me.

JQUERY:

$(function () {
    var arr = {"name":"susheel", "rollNo:" :"123423"};
    $.ajax({
        url: 'http://localhost:8080/restapi/test',
        type: 'POST',
        data: JSON.stringify(arr),
        contentType: 'application/json; charset=utf-8',
        dataType: 'json',
        async: false,
        success: function (msg) {
            alert(msg);
        }
    });
});

Restful webservice code:

import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

@Path("/test")
public class ProjectInfo {      
    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public String submitProject(String s) {        
        return s;
    }
}

Answer 1

You need to add annotation like this:

public String submitProject(@FormParam("mydata") String test) {

If you were doing a get request and attaching to url you would use:

@QueryParam("mydata") String test

You probably want something like:

data: {mydata : JSON.stringify(arr)}

UPDATE*************************************************************************

$(function () {
    var arr = {"name":"susheel", "rollNo:" :"123423"};
    $.ajax({
        url: 'http://localhost:8080/restapi/test',
        type: 'POST',
        data: {name : "susheel", rollno : "123423"},
        contentType: 'application/json; charset=utf-8',
        dataType: 'json',
        async: false,
        success: function (msg) {
            alert(msg);
        }
    });
});

@XmlRootElement()
public class Student {
    private String name;
    private String rollNo;
    public Student()
    {
    }
    public Student(String name, String rollNo)
    {
        this.name = name;
        this.rollNo = rollNo;
    }
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getRollNo() {
        return rollNo;
    }

    public void setRollNo(String rollNo) {
        this.rollNo = rollNo;
    }
}


import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

@Path("/test")
public class ProjectInfo {      
    @POST
    @Produces(MediaType.APPLICATION_JSON)
    public Student submitProject(@FormParam("name") String name, @FormParam("rollno") String rollNo) {
        Student student = new Student(name, rollNo);      
        return student;
    }
}

Answer 2

You need to return a response object like so:

import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

@Path("/test")
public class ProjectInfo {      
    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public Response submitProject(Student s) {        
        return Response.status(Response.Status.OK).entity(s).build();
    }
}

You do not really need to provide a toString that returns a json representation. Your jax-rs implementation will know how to serialize your object into json.

Also, if the body of the post does not contain anything else but the json representation of the object, then you do not need to provide a @FormDataParam annotation in the argument list.

This assuming that you have configured your application to use a jax-rs implementation like jersey with the correct servlet configuration etc.

The following link might help for application set up: How to set up JAX-RS Application using annotations only (no web.xml)?

Answer 3

there is a really easy to use json library from ceadarsoft, that might help you. It translates Json objects to Java objects without the need for annotations on your model.

The maven dependency is:

<dependency>
    <groupId>com.cedarsoftware</groupId>
    <artifactId>json-io</artifactId>
    <version>2.7.1</version>
</dependency>

Answer 4

This is how it worked for me the way I wanted.

import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import org.codehaus.jettison.json.JSONObject;

@Path("/test")
public class ProjectInfo {      
    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public String submitProject(JSONObject obj) {  
        //read the json object data and insert the content to DB.
        //generate the response you like and return it
        //ObjectMapper class from codehaus can be used to generated desired json response.
        return generatedJSONResponse;
    }
}

Thanks everybody for your inputs which helped me solve my problem.