Revision history [back]

There are several ways to create JSON in Android:

1. Using JSONObject and JSONArray classes:

JSONObject jsonObject = new JSONObject();
jsonObject.put("name", "John");
jsonObject.put("age", 30);

JSONArray jsonArray = new JSONArray();
jsonArray.put("red");
jsonArray.put("blue");
jsonArray.put("green");

jsonObject.put("colors", jsonArray);
String jsonString = jsonObject.toString();

1. Using Gson library:

Gson gson = new Gson();

// Convert an object to JSON
Person person = new Person("John", 30);
String jsonString = gson.toJson(person);

// Convert a JSON string to an object
String jsonInput = "{\"name\":\"John\",\"age\":30}";
Person person = gson.fromJson(jsonInput, Person.class);

1. Using Jackson library:

ObjectMapper mapper = new ObjectMapper();

// Convert an object to JSON
Person person = new Person("John", 30);
String jsonString = mapper.writeValueAsString(person);

// Convert a JSON string to an object
String jsonInput = "{\"name\":\"John\",\"age\":30}";
Person person = mapper.readValue(jsonInput, Person.class);

Note: In all the above examples, Person is a custom class that has name and age fields.