Spring根据逻辑分层配置

背景：

通常简单的项目，一个spring.xml的配置文件即可搞定，但是当项目足够大的时候，我们如果将web ，service ，dao这些层的配置都放在spring.xml中，那这个配置文件将相当庞大和混乱，不易维护。

解决：

一个比较好的做法是将配置文件分为三层写三个配置文件（spring-web.xml , spring-service.xml, spring-dao.xml）配置方法如下：

web.xml:
[html]
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-*.xml</param-value>
</context-param>

spring-web.xml:

[html]
<?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:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

    <bean id="messageServlet" class="com.downjoy.app.messageboard.ui.web.wml.MessageCtrlServlet">
        <property name="messageService" ref="messageService"/>
    </bean>
    <bean id="userServlet" class="com.downjoy.app.messageboard.ui.web.wml.UserCtrlServlet">
        <property name="userService" ref="userService"/>
    </bean>
</beans>

spring-service.xml

[html]
<?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:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

    <bean id="messageService" class="com.downjoy.app.messageboard.common.service.MessageServiceImpl">
        <property name="messageDAO" ref="messageDAO"/>
    </bean>
    <bean id="userService" class="com.downjoy.app.messageboard.common.service.UserServiceImple">
        <property name="userDAO" ref="userDAO"/>
    </bean>
</beans>

pring-dao.xml

[html]
<?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:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

<bean id="messageDAO" class="com.downjoy.app.messageboard.common.dao.ibatis.MessageDAOImpl"/>
<bean id="userDAO" class="com.downjoy.app.messageboard.common.dao.ibatis.UserDAOImpl"/>
</beans>

当然还有一种方式就是在各个子配置文件中，将需要的父配置文件import进来，这里不具体展开。

补充：软件开发 , Java ,