Book Image

Spring 5 Design Patterns

By : Dinesh Rajput
Book Image

Spring 5 Design Patterns

By: Dinesh Rajput

Overview of this book

Design patterns help speed up the development process by offering well tested and proven solutions to common problems. These patterns coupled with the Spring framework offer tremendous improvements in the development process. The book begins with an overview of Spring Framework 5.0 and design patterns. You will understand the Dependency Injection pattern, which is the main principle behind the decoupling process that Spring performs, thus making it easier to manage your code. You will learn how GoF patterns can be used in Application Design. You will then learn to use Proxy patterns in Aspect Oriented Programming and remoting. Moving on, you will understand the JDBC template patterns and their use in abstracting database access. Then, you will be introduced to MVC patterns to build Reactive web applications. Finally, you will move on to more advanced topics such as Reactive streams and Concurrency. At the end of this book, you will be well equipped to develop efficient enterprise applications using Spring 5 with common design patterns
Table of Contents (20 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface

Understanding AOP proxies


As you know that, Spring AOP is proxy-based. It mean Spring creates the proxy to weave the aspect between the business logic that is, in target object. It is based on the Proxy and Decorator design pattern. Let's see TransferServiceImpl class as an implementation of TransferService interface:

    package com.packt.patterninspring.chapter6.bankapp.service; 
    import org.springframework.stereotype.Service; 
    public class TransferServiceImpl implements TransferService { 
      @Override 
      public void transfer(String accountA, String accountB, Long 
      amount) { 
        System.out.println(amount+" Amount has been tranfered from 
        "+accountA+" to "+accountB); 
      } 
    } 

Caller invokes this service (transfer() method) directly by the object reference, let's see the following figure to illustrate more:

As you can see that caller could directly call the service and do the task assigned to it.

But you declare this TransferService as a target for the...