001 Spring Introduction

One. Overview

Spring, as a fact standard under the current JEE, has very good features, the core of which is IOC and AOP.

Based on this, we can integrate technologies such as ORM,WEB,MQ, so we can say that spring can help us in all aspects of development.

Two. IOC and AOP

IOC: In spring, it is embodied in the management of bean creation and dependency.

In our application, almost all business components can be called beans, so creating and managing beans is the most complex part of our development.

The IOC can help us to solve this problem, help us create the bean we want, and inject the dependency into the bean.

This is the IOC container, Spring uses the container to manage all of this, and our business components are hosted in the IOC container.

AOP: When our business components are hosted in the IOC, the container controls the bean's life cycle, so we can easily use dynamic proxies to do business decoupling.

AOP is the aspect-oriented programming, which is a means of separating and weaving the system business and business code.

Because AOP is a bad idea, spring is a feature that our developers seldom use, so the benefits of containers are lost in a large part, but using AOP is really simple,

But understanding the concept is really the most important aspect.

Three. Integration

The most common thing about our developers is that spring integrates various frameworks, and I don't want to say much here.

Because we understand that IOC and AOP understand the principles of spring integration, and when it comes to problems, you can analyze the problem, or spring is the equivalent of not learning,

Just stay on the level of use.

Four. Spring architecture

　　

As we can see from the above figure, the IOC is the lowest level, then the AOP uses the IOC implementation, and then spring integrates the other components.

After that, we'll do it at this level.

001 Spring Introduction