SPRING IOC注入方式过程解析

<?xml version= "1.0" encoding= "UTF-8"?>
<beans xmlns= "http://www.springframework.org/schema/beans"
xmlns:xsi= "http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation= "http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd"
default-init-method= "init" default-destroy-method= "destroy">
<!-- 
<bean id="InjectionService" class="Main.InjectionServiceImpl">
<property name="injectionDAO" ref="InjectionDAO"></property>
 </bean>
 -->
 <bean id="InjectionService" class="Main.InjectionServiceImpl">
<constructor-arg name="injectionDAO" ref="InjectionDAO"></constructor-arg>
 </bean>
<bean id="InjectionDAO" class= "Main.InjectionDAOImpl"> </bean>

</beans>