How to write JSON object to File in Java?

In this tutorial, I’ll show you how to write JSON data to a file using JSON.simple .

JSON.simple is a simple Java toolkit for JSON. You can use JSON.simple to encode or decode JSON text.

Maven Dependency:

<groupId>com.googlecode.json-simple</groupId>

<artifactId>json-simple</artifactId>

</dependency>

Features:

Full compliance with JSON specification (RFC4627) and reliable (see compliance testing)
Provides multiple functionalities such as encode, decode/parse and escape JSON text while keeping the library lightweight
Flexible, simple and easy to use by reusing Map and List interfaces
Supports streaming output of JSON text
Stoppable SAX-like interface for streaming input of JSON text (learn more)
Heap based parser
High performance (see performance testing)
No dependency on external libraries
Both of the source code and the binary are JDK1.2 compatible

Here is a file1.txt content:

{

"Name": "crunchify.com",

"Author": "App Shah",

"Company List": [

"Compnay: eBay",

"Compnay: Paypal",

"Compnay: Google"

]

}

Java Code:

package com.crunchify.tutorials;

import java.io.FileWriter;

import java.io.IOException;

import org.json.simple.JSONArray;

import org.json.simple.JSONObject;

/**

* @author Crunchify.com

public class CrunchifyJSONFileWrite {

@SuppressWarnings("unchecked")

public static void main(String[] args) throws IOException {

JSONObject obj = new JSONObject();

obj.put("Name", "crunchify.com");

obj.put("Author", "App Shah");

JSONArray company = new JSONArray();

company.add("Compnay: eBay");

company.add("Compnay: Paypal");

company.add("Compnay: Google");

obj.put("Company List", company);

// try-with-resources statement based on post comment below :)

try (FileWriter file = new FileWriter("/Users/<username>/Documents/file1.txt")) {

file.write(obj.toJSONString());

System.out.println("Successfully Copied JSON Object to File...");

System.out.println("\nJSON Object: " + obj);

}

In above example FileWriter instance is declared in a try-with-resource statement, it will be closed regardless of whether the try statement completes normally or abruptly. You don’t have catch IOException or no need to mention finally block.

Compare above code with below with try, catch, finally code. Above code is just 4 lines compare to 11 lines below.

Output:

Successfully Copied JSON Object to File...

JSON Object: {"Name":"crunchify.com","Author":"App Shah","Company List":["Compnay: eBay","Compnay: Paypal","Compnay: Google"]}

Reference:

https://github.com/fangyidong/json-simple

Download JSON.simple from here.

Would love to know what you think. Chime in and share it as a comment. Don’t forget to share this guide!

MAK

Uhm.. try with resources does not automatically handle IOException, the only reason why you don’t have a catch in your try, is because you’re throwing IOException in your method signature..
- App Shah
  
  That’s right MAK. It’s users choice the why they want to choose coding style.
bigbadlosangeles

try-with-resources;

try (FileWriter file = new FileWriter(“/Users//Documents/file1.txt”)) {
…
} catch(IOException exc) {
…
}

makes it so you don’t need the finally bit of the try-catch. I believe you have to have JDK 7+ however

Anyway, thanks for sharing this, helped me do exactly what i wanted to.
- App Shah
  Hi there – I agree. Just updated above tutorial and added file1.txt content.
  
  { "Name": "crunchify.com", "Author": "App Shah", "Company List": [ "Compnay: eBay", "Compnay: Paypal", "Compnay: Google" ] }