我们可以在xml中开启自动扫描

<?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">

	<context:component-scan base-package="componentscan"/>
	<bean id="XMLComponentDAO" class="componentscan.XMLComponentDAO">
		<property name="jdbcConnection"
			ref="XMLComponentJdbcConnection" />
	</bean>

	<bean id="XMLComponentJdbcConnection"
		class="componentscan.XMLComponentJdbcConnection">
	</bean>


</beans>