Dagger vs Spring Framework: Which One Should You Choose?

Are you building a Java application and confused about which dependency injection framework to use? Let’s break down two popular options — Dagger and Spring Framework — in simple terms with plenty of examples.

What is Dependency Injection?

Before diving into Dagger and Spring, let’s understand what dependency injection means.

Imagine you’re making coffee. You need:

• Coffee beans
• Water
• A coffee machine

Instead of your coffee cup finding its own coffee beans and water, someone hands these things to your cup. That’s dependency injection — giving an object what it needs rather than making it find or create these things itself.

In code, instead of a class creating its own dependencies, they are “injected” from outside.

Dagger: The Lightweight Champion

Dagger is a dependency injection framework made by Google. It focuses on:

• Speed
• Compile-time checking
• No reflection (a technique where code can examine itself while running)
• Small size

Key Features of Dagger