Spring学习笔记（1）PropertyPlaceholderConfigurer

PropertyPlaceholderConfigurer

Spring的框架中为提供了一个BeanFactoryPostProcessor的实体类别： org.springframework.beans.factory.config.PropertyPlaceholderConfigurer
可以将一些动态参数，移出至.properties中，如此的安排可以让XML定义系统相关设定（不常变动），而.properties可以作为客户根据实际自定义一些相关参数。（如不同人数据库的不同密码）
applicationConfig.xml

<beans>
        <bean id="propertyConfigurer"
		class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="location">
			<value>/WEB-INF/db.properties</value>
		</property>
	</bean>

	<bean id="dataSource"
		class="org.logicalcobwebs.proxool.ProxoolDataSource">
		<property name="driver">
			<value>${driver}</value>
		</property>
		<property name="driverUrl">
			<value>${driverUrl}</value>
		</property>
		<property name="user">
			<value>${user}</value>
		</property>
		<property name="password">
			<value>${password}</value>
		</property>
		<property name="alias">
			<value>spring</value>
		</property>
		<property name="houseKeepingSleepTime">
			<value>90000</value>
		</property>
		<property name="prototypeCount">
			<value>5</value>
		</property>
		<property name="maximumConnectionCount">
			<value>100</value>
		</property>
		<property name="minimumConnectionCount">
			<value>10</value>
		</property>
		<property name="trace">
			<value>true</value>
		</property>
		<property name="verbose">
			<value>true</value>
		</property>
	</bean>
</beans>

db.properties

driver=com.mysql.jdbc.Driver
driverUrl=jdbc:mysql://localhost/securedoc?user=root&password=sqladmin&useUnicode=true&characterEncoding=GBK
user=root
password=sqladmin