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+23 votes

I am having trouble using Gson. I don't understand how to format or use it

asked in CSC305 Fall 2023 by (1 point)

2 Answers

+6 votes

Gson is a Java library that can be used to convert Java Objects into their JSON representation and vice versa. It can also be used to convert a JSON string to an equivalent Java object.
To serialize an object (convert an object to a JSON string), you can use the Gson.toJson() method. Here’s how you do it:
MyObject obj = new MyObject();
// Convert the object to JSON
String json = gson.toJson(obj);

To deserialize a JSON string (convert a JSON string to an object), you use the Gson.fromJson() method. Here’s how:
Gson gson = new Gson();
MyObject obj = gson.fromJson(json, MyObject.class);
Using Gson should be straightforward once you grasp the basics of serialization and deserialization.
You can also refer to MovieTrackerRepo for further reference.

answered by (2.1k points)
+3 votes

Here's a simple example of a Java class and how you can use Gson to work with it:

import com.google.gson.Gson;

public class MyObject {

private String name;
private int age;

public MyObject(String name, int age) {
    this.name = name;
    this.age = age;

// Getter and setter methods (or public fields) here

public static void main(String[] args) {
    // Create a Gson instance
    Gson gson = new Gson();

    // Convert a Java object to JSON
    MyObject obj = new MyObject("John", 30);
    String json = gson.toJson(obj);
    System.out.println("Java to JSON: " + json);

    // Convert JSON to a Java object
    MyObject newObj = gson.fromJson(json, MyObject.class);
    System.out.println("JSON to Java: " + newObj.getName() + ", " + newObj.getAge());


answered by (241 points)