一、创建类

在类上面添加创建对象的注解 @Component(value = “user”)

User.java

/*
    注解里面value属性值可以不写
    默认是类名称,首字母小写
*/
@Component(value = "user")  //等于<bean id="userService" class="**.L_注解开发.a_对象创建">
public class User {
    public void add(){
        System.out.println("add方法......");
    }
}

#

二、编写配置文件

开启组件扫描：

bean21.xml

<?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">
    <!--开启组件扫描
            1.若要扫描多个包,多个包用逗号隔开
            2.若要扫描多个包,扫描包的上级目录
            -->
    <context:component-scan base-package="com.health.IOC.L_注解开发.a_对象创建"></context:component-scan>
</beans>

#

三、测试

TestLa.java

public class TestLa {
    public static void main(String[] args) {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("com/health/IOC/L_注解开发/a_对象创建/bean21.xml");
        User user = context.getBean("user", User.class);
        System.out.println(user);
        user.add();
    }
}