Convert JSON Array to List of Long Type in Java
In this guide, you will learn how to convert a JSON Array into a List of Long values using the Gson library in Java.
First, install Gson library in your project.
For Maven:
<dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.10.1</version> </dependency>
For Gradle:
implementation group: 'com.google.code.gson', name: 'gson', version: '2.10.1'
This code snippet demonstrates how to convert a JSON array into a List of Long values in Java:
import java.util.List; import java.lang.reflect.Type; import com.google.gson.Gson; import com.google.gson.reflect.TypeToken; public class Example { public static void main(String[] args) { // Json array data String jsonArrayExampleData = "[\"123\",\"456\",\"456\",\"232\"]"; // creating an object of Gson Gson gson = new Gson(); // Converting to List of Long type Type type = new TypeToken>() {}.getType(); List
list = gson.fromJson(jsonArrayExampleData, type); System.out.println(list); } }
The output of the above code is as follows:
[123, 456, 456, 232]
Here, in this example, the Example class contains the main method, where the JSON array data that we want to convert is defined as a string: String jsonArrayExampleData = "[\"123\",\"456\",\"456\",\"232\"]";.
In the main method, an instance of the Gson class is created: Gson gson = new Gson();. Gson is a Java library that provides methods for converting Java objects to JSON and vice versa. To convert the JSON array to a List of Long values, a Type object is defined using the TypeToken class: Type type = new TypeToken>() {}.getType();
. This captures the generic type information of List