spring 自动扫描组件

• @Component – 指示自动扫描组件。
• @Repository – 表示在持久层DAO组件。
• @Service – 表示在业务层服务组件。
• @Controller – 表示在表示层控制器组件。

在相应的xml文件中做如下声明即可

<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-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd">

<context:component-scan base-package="com.yiibai.customer" />

</beans>

 DAO层

import org.springframework.stereotype.Repository;

@Repository
public class CustomerDAO
{
@Override
public String toString() {
return "Hello , This is CustomerDAO";
}
}

service层

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.yiibai.customer.dao.CustomerDAO;

@Service
public class CustomerService
{
@Autowired
CustomerDAO customerDAO;

@Override
public String toString() {
return "CustomerService [customerDAO=" + customerDAO + "]";
}

}