How to Convert List to JSON in Java using Gson API

on December 2, 2016

Post Views: 2,972

Convert List to JSON in Java

This is a simple program about, How to Convert List to JSON in Java using Gson API. The Gson API can be downloaded from here

Product.java

package com.dineshkrish.json;
public class Product {
private int productId;
private String productName;
private String productDesc;
public int getProductId() {
return productId;
}
public void setProductId(int productId) {
this.productId = productId;
}
public String getProductName() {
return productName;
}
public void setProductName(String productName) {
this.productName = productName;
}
public String getProductDesc() {
return productDesc;
}
public void setProductDesc(String productDesc) {
this.productDesc = productDesc;
}
}

ListConversion.java

package com.dineshkrish.json;
import java.util.ArrayList;
import java.util.List;
import com.google.gson.Gson;
public class ListConversion {
public static void main(String[] args) {
Gson gson = new Gson();
List<Product> list = new ArrayList<Product>();
// Defining 2 Product Object
Product p1 = new Product();
p1.setProductId(101);
p1.setProductName("Item 1");
p1.setProductDesc("About Item1");
Product p2 = new Product();
p2.setProductId(102);
p2.setProductName("Item 2");
p2.setProductDesc("About Item2");
Product p3 = new Product();
p3.setProductId(103);
p3.setProductName("Item 3");
p3.setProductDesc("About Item3");
list.add(p1);
list.add(p2);
list.add(p3);
// Covert List to Json
String jsonString = gson.toJson(list);
System.out.println(jsonString);
}
}

Output

[{“productId”:101,”productName”:”Item 1″,”productDesc”:”About Item1″},{“productId”:102,”productName”:”Item 2″,”productDesc”:”About Item2″},{“productId”:103,”productName”:”Item 3″,”productDesc”:”About Item3″}]