Dependency Injection is a design pattern that allows us to remove the hardcoded dependencies and make our application loosely coupled, extendable, and maintainable. We can implement dependency injection to move the dependency resolution from compile-time to runtime. This book will be your one-stop guide to writing loosely coupled code using the latest features of Java 9 with frameworks such as Spring 5 and Google Guice.
This book is for Java developers who would like to understand how to implement Dependency Injection in their applications. Prior knowledge about the Spring and Guice frameworks and Java programming is assumed.
Chapter 1, Why Dependency Injection?, gives you a detailed insight into various concepts, such as Dependency Inversion of Principle (DIP), Inversion of Control (IoC), and Dependency Injection (DI). It also talks about practical use cases where DI is commonly used.
Chapter 2, Dependency Injection in Java 9, gets you acquainted with Java 9 features and its modular framework, and explains how to implement DI using the service loader concept.
Chapter 3, Dependency Injection with Spring, teaches you how to manage dependency injection in the Spring framework. It also describes a different way to implement DI using Spring.
Chapter 4, Dependency Injection with Google Guice, talks about Guice and its dependency mechanism, and it teaches us dependency binding and the various injection methods of the Guice framework.
Chapter 5, Scopes, teaches you about the different scopes defined in the Spring and Guice frameworks.
Chapter 6, Aspect-Oriented Programming and Interceptors, shows the purpose of Aspect-Oriented Programming (AOP), how it solves different design problems by isolating repeated code from applications and plug them dynamically using Spring framework.
Chapter 7, IoC Patterns and Best Practices, gives an overview of various design patterns that can use to achieve IoC. Apart from this, you will be acquainted with best practices and anti-patterns to follow while injecting DI.
- It would be good if you know Java, Spring, and the Guice framework. This will help you understand dependency injection
- We assume you have an installation of Java 9, and Maven on your system, before beginning
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