Spring 抽取配置到属性文件的两种方式

在配置时要注意其中的格式传的值是key

jdbc.properties

user=root
password=123456
jdbcUrl=jdbc:mysql:///Spring?serverTimezone=UTC 
driverClass=com.mysql.cj.jdbc.Driver

xml

!--<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location" value="classpath:jdbc.properties"/>
</bean>-->

    <context:property-placeholder location="classpath:jdbc.properties"/>
    <!--配置c3p0连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${driverClass}"/>
        <property name="jdbcUrl" value="${jdbcUrl}"/>
        <property name="user" value="${user}"/>
        <property name="password" value="${password}"/>
    </bean>

    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <constructor-arg>
            <ref bean="dataSource" />
        </constructor-arg>
    </bean>