How to pretty print JSON using Moshi

By mkyong | Updated: April 30, 2024

Viewed: 1,120 (+644 pv/w)

Tags: java json moshi parse json pretty print json

This article shows how to use Moshi’s JsonAdaptor indent method to enable the pretty print JSON.

Table of contents:

• 1. Download Moshi
• 2. Compact print JSON (Default)
• 3. Pretty print JSON using Moshi
• 4. Download Source Code
• 5. References

P.S Tested with Moshi 1.15.1

1. Download Moshi

Declare moshi in the pom.xml.

    <dependency>
        <groupId>com.squareup.moshi</groupId>
        <artifactId>moshi</artifactId>
        <version>1.15.1</version>
    </dependency>

2. Compact print JSON (Default)

By default, Moshi prints JSON strings in compact format:

package com.mkyong.json.model;

public class Person {

    private String name;
    private int age;

    // getters, setters, constructors and etc...
}

package com.mkyong.json.moshi;

import com.mkyong.json.model.Person;
import com.squareup.moshi.JsonAdapter;
import com.squareup.moshi.Moshi;

public class PrettyPrintJsonExample {

    public static void main(String[] args) {

        Moshi moshi = new Moshi.Builder().build();
        JsonAdapter<Person> jsonAdapter = moshi.adapter(Person.class);

        Person person = new Person("mkyong", 42);

        try {
            String json = jsonAdapter.toJson(person);
            System.out.println(json);
        } catch (Exception e) {
            System.err.println("Error parsing JSON: " + e.getMessage());
        }

    }
}

Output

{"age":42,"name":"mkyong"}

3. Pretty print JSON using Moshi

In the JsonAdapter’s indent method, puts two spaces, this will tell Moshi to format the JSON string with each new level indented by two spaces, making the structure of the JSON clear and easy to understand.

  // indent using two spaces
  JsonAdapter<Person> jsonAdapter = 
        moshi.adapter(Person.class).indent("  ");

package com.mkyong.json.moshi;

import com.mkyong.json.model.Person;
import com.squareup.moshi.JsonAdapter;
import com.squareup.moshi.Moshi;

public class PrettyPrintJsonExample {

    public static void main(String[] args) {

        Moshi moshi = new Moshi.Builder().build();

        // two spaces
        JsonAdapter<Person> jsonAdapter = 
              moshi.adapter(Person.class).indent("  ");

        Person person = new Person("mkyong", 42);

        try {
            String json = jsonAdapter.toJson(person);
            System.out.println(json);
        } catch (Exception e) {
            System.err.println("Error parsing JSON: " + e.getMessage());
        }

    }
}

Output

{
  "name" : "mkyong",
  "age" : 42
}

4. Download Source Code

5. References

• Moshi Github
• Parse JSON using Moshi
• Write JSON to a file using Moshi
• How to enable pretty print JSON with Jackson
• Parse JSON string with Jackson