JSON also known as JavaScript Object Notation is a widely used format for exchanging data between a server and a client.

In this article, we will see how to parse a JSON input stream using the Jackson library in Java.

Jackson Library:

Jackson is a high-performance JSON parsing and generation library for Java which provides a simple and efficient way to parse JSON data into Java objects.

Let us see how to parse a JSON input using the Jackson library.

Add dependencies

First, let us include the Jackson Library’s dependency in your project. For Maven, please add the following dependency to your pom.xml.


The version I am using above in the dependency XML might not be the latest one. You can visit the Jackson official page and see the latest version.

Import the required classes

import com.fasterxml.jackson.databind.*;
import java.io.*;

Parsing the JSON from the input stream

See the following example on how to parse the JSON from the input stream.

public class JsonParsingExample {
    public static void main(String[] args) {
        try {
            // Create a JSON parser
            ObjectMapper objectMapper = new ObjectMapper();

            // Create an InputStream (you can replace this with your input source)
            InputStream inputStream = new FileInputStream("data.json");

            // Parse the JSON input stream into a JsonNode object
            JsonNode jsonNode = objectMapper.readTree(inputStream);

            // Process the JSON data
            String value = jsonNode.get("key").asText();
            System.out.println("Value of 'key': " + value);

            // Close the input stream
        } catch (IOException e) {

In the above example, replace "data.json" with the path to your JSON input stream. In this example, we use a JsonNode object to navigate and retrieve data from the JSON structure.


For more information, please visit the Jackson git repository.


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