Using JsonPath in Java to Simplify JSON Data Access

JsonPath is a DSL for reading JSON documents, similar to how XPath works with XML.

It is included in the spring-boot-starter-test package and can be added via Maven dependency:

<dependency>
    <groupId>com.jayway.jsonpath</groupId>
    <artifactId>json-path</artifactId>
    <version>2.7.0</version>
    <scope>compile</scope>
</dependency>

The library’s GitHub repository is https://github.com/json-path/JsonPath.

Example JSON data and a Java demo show how to load a JSON file, parse it with JsonPath, and read the array of books using the expression "$.store.book[*]".

import com.jayway.jsonpath.DocumentContext;
import com.jayway.jsonpath.JsonPath;
import net.minidev.json.JSONArray;
import org.apache.commons.io.IOUtils;
import java.io.IOException;
import java.io.InputStream;

public class JsonPathDemo {
    public static void main(String[] args) throws IOException {
        InputStream resourceAsStream = JsonPathDemo.class.getClassLoader()
                .getResourceAsStream("jsonpath.json");
        String json = IOUtils.toString(resourceAsStream);
        System.out.println(json);
        DocumentContext documentContext = JsonPath.parse(json);
        JSONArray bookJson = documentContext.read("$.store.book[*]");
        System.out.println(bookJson);
    }
}

To rename keys in a JSON structure, JsonPath provides the renameKey method, allowing different source JSONs to be transformed into a unified model, e.g., changing price to total-price across all book entries.

DocumentContext documentContext = JsonPath.parse(json);
documentContext.renameKey("$.store.book[*]", "price", "total-price");
System.out.println(documentContext.jsonString());

Command‑line tools such as jq can also be used for JSON processing.

In summary, JsonPath offers a convenient DSL for JSON manipulation in Java applications, and jq provides a powerful CLI alternative.