turn object into json code example

Example 1: Javascript object to JSON string

var person={"first_name":"Tony","last_name":"Hawk","age":31};
var personJSONString=JSON.stringify(person);

Example 2: convert data into json format in javascript

Use the JavaScript function JSON.parse() to convert text into a JavaScript object:
var obj = JSON.parse('{ "name":"John", "age":30, "city":"New York"}');

Example 3: convert json to object

Jackson Data-bind depdendency that take care of 
Converting between 
JSON to Java Object 
and 
Java Object to JSON

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.0</version>
</dependency>