Once annotation was introduced in Java 1.5, Spring Framework also added support for annotations in version 2.5.

Spring provides several standard annotations, which are used on stereotype classes in the application. By using such annotations, we don't need to maintain bean definitions in XML files. We just need to write one line, <context:component-scan>, in the Spring XML configuration for a scanning component, and the Spring IoC container scans the defined package to register all the annotated classes and their bean definitions in the application context.

Specifically, @Component and @Service are used to scan beans in the provided package. Here, we will use @Service annotation, because the @Service annotation is too specialized for the @Component annotation. It doesn’t give us any extra behavior than the @Component explanation, but it’s better to choose @Service over @Component in service-layer classes, since it indicates expectations way better.

For singleton and prototype beans, our application-context.xml file will be the same, and looks as follows:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

  <!-- <context:annotation-config /> -->
  <context:component-scan base-package="com.packt.springbeanannotation" />
      
</beans>