How to convert JSON string to Java object?

In the following example we will convert JSON string to Java object using ObjectMapper class from the Jackson library. This class provides a method readValue(String, Class<T>) which will deserialize a JSON string into Java object. The first argument to the method is the JSON string and the second parameter is the result type of the conversion.

package org.kodejava.example.jackson;

import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.IOException;

public class JsonToObject {
    public static void main(String[] args) {
        String json = "{\"id\": 1, \"name\": \"The Beatles\"}";

        ObjectMapper mapper = new ObjectMapper();
        try {
            Artist artist = mapper.readValue(json, Artist.class);
            System.out.println("Artist = " + artist);

            System.out.println("artist.getId() = " + artist.getId());
            System.out.println("artist.getName() = " + artist.getName());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

And here is the definition of Artist class.

package org.kodejava.example.jackson;

public class Artist {
    private Long id;
    private String name;

    public Artist() {
    }

    public Artist(Long id, String name) {
        this.id = id;
        this.name = name;
    }

    // Getters & Setters

    @Override
    public String toString() {
        return "Artist{" +
            "id=" + id +
            ", name='" + name + '\'' +
            '}';
    }
}

The code snippet above will print to following output:

Artist = Artist{id=1, name='The Beatles'}
artist.getId() = 1
artist.getName() = The Beatles

Maven Dependencies

<!-- http://repo1.maven.org/maven2/com/fasterxml/jackson/core/jackson-databind/2.8.6/jackson-databind-2.8.6.jar -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.8.6</version>
</dependency>

Wayan Saryada

Founder at Kode Java Org
I am a programmer, a runner, a recreational diver, currently live in the island of Bali, Indonesia. Mostly programming in Java, Spring Framework, Hibernate / JPA. If this post help, you can buy me a coffee or tea. Thank you 🥳

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