How do you create a generic class in Java?

Table of Contents

• Introduction
• Creating a Generic Class in Java
  • Defining a Generic Class
  • Example: Creating a Generic Class
  • Working with Multiple Type Parameters
• Benefits of Using Generics
• Conclusion

Introduction

In Java, generics provide a way to define classes, interfaces, and methods with type parameters, allowing you to create type-safe and reusable code. A generic class allows the same class to operate on different types of data without needing to define multiple versions of the same class. This guide explains how to create a generic class in Java and use it effectively with practical examples.

Creating a Generic Class in Java

Defining a Generic Class

To create a generic class, you declare one or more type parameters within angle brackets <> after the class name. These parameters act as placeholders that will be replaced with actual data types when an object of the class is created.

Basic Syntax:

In this example, T is a type parameter representing a generic type. When creating an object of this class, you can specify the actual type for T.

Example: Creating a Generic Class

Here is an example that demonstrates how to create and use a generic class in Java:

Working with Multiple Type Parameters

A generic class can also work with multiple type parameters. For example, if you need a class that works with two different types, you can define it like this:

In this example, Pair<T, U> can hold two different types—T and U. When creating a Pair object, you specify the types for T and U, making the class flexible.

Benefits of Using Generics

1. Type Safety: Generics allow you to catch type errors at compile time, ensuring that you can only pass data of the correct type to a generic class.
2. Code Reusability: With generics, you don't need to write multiple versions of a class to handle different data types.
3. Improved Code Readability: The use of generics provides clarity by clearly indicating the type of objects the class can handle.

Conclusion

Creating a generic class in Java allows you to build flexible, reusable code that can handle different data types in a type-safe way. Using generics improves both code reusability and readability, making your programs more efficient and less prone to runtime errors. By following the examples provided, you can easily implement generic classes and enhance the robustness of your Java applications.