Wednesday, 27 January 2016

Java POJO to JSON using Gson (

Java POJO to JSON using
In many daily development scenarios we come across  situations where we need to convert a JAVA POJO into JSON.

There are many ways that we can use to do so. The following article shows hoe to convert a POJO class into JSON using the Google Gson API.

Step 1:

Download the Gson_2.5.jar file form the link below and place it in your build path.

If you are using Maven then the dependency is

Step 2:

We will start by creating a simple Employee POJO class.


package net.codermag.json.examples;

public class Employee {

 private String name;
 private String email;
 private EmployeeAddress address;

 public void setName(String name) { = name;

 public void setEmail(String email) { = email;

 public void setAddress(EmployeeAddress address) {
  this.address = address;



package net.codermag.json.examples;

public class EmployeeAddress {

 private String city;
 private String state;

 public void setCity(String city) { = city;

 public void setState(String state) {
  this.state = state;

Now that we have the structure of the POJO ready we can now convert the Employee POJO into JSON by running the following code sample.


package net.codermag.json.examples;


public class PojoToJsonExample {

 public static void main(String[] args) {

  // Setting values of the Employee POJO
  Employee emp1 = new Employee();

  EmployeeAddress address = new EmployeeAddress();
  address.setCity("New York");

  // Instantiating GSON
  Gson gson = new Gson();
  String json = gson.toJson(emp1);



{"name":"John","email":"","address":{"city":"New York","state":"USA"}}