步骤一:导入注解开发所需的jar包
* 引入IoC容器必须的6个jar包
* 在引入一个:Spring框架的AOP的jar包,spring-aop-4.2.4.RELEASE.jar
步骤二:创建对应的包结构,编写Java的类
* UserService --- 接口
* UserServiceImpl --- 具体的实现类
步骤三:在src目录下,创建applicationContext.xml的配置文件,引入约束。注意:使用注解的方式,引入的约束与之前的约束有所不同
* 需要引入context的约束,位置:spring-framework-reference\html\xsd-configuration.html中
具体约束:
<?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">
</beans>
步骤四:在applicationContext.xml配置文件中需要开启组件扫描
* Spring的注解开发:组件扫描
<context:component-scan base-package="com.jadan.demo1" />
* 注意:可以采用如下配置
<context:component-scan base-package="com.jadan" /> 这样是扫描com.jadan包下所有的内容
<?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">
<!-- 开启注解的扫描 -->
<context:component-scan base-package="com.jadan"></context:component-scan>
</beans>
步骤五:在UserServiceImpl的实现类上添加注解
* @Component(value="userService")
--- 相当于在XML上配置<bean id="userService" class="com.jadan.demo1.UserServiceImpl" />
/**
* 组件注解,标记类
* <bean id="userService" class="com.jadan.demo1.UserServiceImpl"/> == @Component(value="userService")
*/
@Component(value="userService")
public class UserServiceImpl implements UserService {
public void sayHello() {
System.out.println("Hello Spring...");
userDao.save();
}
}
步骤六:编写测试代码
public class Demo1 {
/**
* 使用注解的方式
*/
@Test
public void run1() {
// 创建工厂,加载核心配置文件
ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
// 从工厂中获取对象
UserService us = (UserService) ac.getBean("userService");
us.sayHello();
}
}