Java Lesson 51 – Spring Intro | Dataplexa

Spring Framework Introduction

So far, you have built Java applications using core language features, collections, JDBC, and web technologies like Servlets and JSP.

As applications grow larger, managing objects, configurations, and dependencies manually becomes complex and error-prone.

This is where the Spring Framework comes in. Spring helps developers build large, scalable, and maintainable Java applications.

What Is the Spring Framework?

Spring is an open-source Java framework designed to simplify enterprise application development.

Instead of writing complex setup code, Spring focuses on managing objects and wiring them together automatically.

At its core, Spring is about loosely coupled design.

Before Spring, enterprise Java development relied heavily on complex technologies that required a lot of configuration and boilerplate code.

Spring was created to:

Consider a traditional Java application where one class directly creates another.


public class OrderService {
    PaymentService paymentService = new PaymentService();
}

This creates tight coupling. If PaymentService changes, OrderService must also change.

Spring removes this problem by managing object creation for you.

You focus on business logic, not object wiring.

Spring is not a single tool — it is a framework with multiple modules.

We will cover these step by step in upcoming lessons.

In Spring, an object managed by the framework is called a Bean.

Instead of creating objects using new, Spring creates and manages them for you.

This allows better control, flexibility, and testing.

Imagine an e-commerce system:

Spring manages how these services are connected, making the system easy to extend or modify.

Traditional Java applications require developers to manage object creation manually.

Spring handles this automatically using configuration and annotations.

This leads to more readable and maintainable code.

Most modern Java backend systems are built using Spring.

Spring is a large framework. Do not try to memorize everything at once.

We will focus on understanding concepts first, then apply them practically in later lessons.

In the next lesson, we will dive into Spring IoC (Inversion of Control) and understand how Spring manages objects internally.