Spring_导入外部属性文件

导入外部属性文件

举个栗子：spring配置druid（数据库连接池）

1 常规配置

<?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">

    <bean id="druid" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/dbName"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>
</beans>

2 导入外部属性配置

导入外部文件，需要在配置文件的头部配置context

2.1 外部文件

文件路径：resources/properties/druid.properties

prop.classname=com.mysql.jdbc.Driver
prop.url=jdbc:mysql://localhost:3306/dbName
prop.username=root
prop.password=root

2.2 bean配置文件

<?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:property-placeholder location="classpath:properties/druid.properties"/>

    <bean id="druid" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${prop.classname}"/>
        <property name="url" value="${prop.url}"/>
        <property name="username" value="${prop.username}"/>
        <property name="password" value="${prop.password}"/>
    </bean>

</beans>