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This article mainly introduces the relevant knowledge of Spring using annotations to develop methods, the content is detailed and easy to understand, the operation is simple and fast, and has a certain reference value, I believe you will have something to gain after reading this article on the methods of Spring development using annotations, let's take a look at it.

To use annotation development after Spring4, you must ensure that the aop package is imported

Using annotations requires importing context constraints to add support for annotations

@ Component: if the component is placed on the class, it means that the class is managed by Spring and is called bean.

Import org.springframework.stereotype.Component;// is equivalent to @ Componentpublic class User {public String name = "xxx";}

@ Value

Import org.springframework.beans.factory.annotation.Value;import org.springframework.stereotype.Component;// is equivalent to @ Componentpublic class User {@ Value ("xxx") / / equivalent to public String name;}

Or

Import org.springframework.beans.factory.annotation.Value;import org.springframework.stereotype.Component;// is equivalent to @ Componentpublic class User {public String name; @ Value ("xxx") public void setName (String name) {this.name = name;}}

@ Component has several derivative annotations that we will layer according to the MVC three-tier architecture in Web development.

Dao [@ Repository]

Service [@ Service]

Controller [@ Controller]

These four annotation functions all represent registering a class with Spring to assemble Bean.

The scope of the annotation @ Scope

@ Scope is placed on the class. The default is singleton mode.

@ Scope (prototype) is a prototype pattern, creating a new object each time

Its effect is equivalent to

Add:

The code below @ Scope ("singleton") or @ Scope singleton mode outputs true.

@ Scope ("prototype") the following code outputs the result as false

Xml vs comments

Xml is more versatile and suitable for any occasion, simple and convenient maintenance.

Annotations are not used by their own class without talking about the relatively complex maintenance.

Best practice: xml is used to manage bean

Annotations are only responsible for completing the injection of attributes

In the process of using it, we need to pay attention to the following code

Examples of best practices

Import org.springframework.beans.factory.annotation.Value;public class User {@ Value ("XXX") public String name; public void setName (String name) {this.name = name;}} this is the end of the article on "methods for developing Spring using annotations". Thank you for reading! I believe you all have a certain understanding of "the method of Spring development using annotations". If you want to learn more, you are welcome to follow the industry information channel.

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