spring可以用什么方式来注入properties文件呢？

通过<context:property-placeholder />标签
<?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:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop" 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
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd">

    <context:property-placeholder location="classpath:mysql.properties" ignore-unresolvable="true"/>

    <!-- 配置数据源 -->
    <bean abstract="true" name="parentDatasource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${ds1.jdbc.driverClassName}" />
        <!-- 初始化连接大小 -->
        <property name="initialSize" value="1" />
        <!-- 连接池最大使用连接数量 -->
        <property name="maxActive" value="100" />
        <!-- 连接池最小空闲 -->
        <property name="minIdle" value="20" />
        <!-- 获取连接最大等待时间 -->
        <property name="maxWait" value="30000" />
        <!-- <property name="poolPreparedStatements" value="true" /> -->
        <!-- <property name="maxPoolPreparedStatementPerConnectionSize" value="33" /> -->
        <property name="validationQuery" value="SELECT 1" />
        <property name="testOnBorrow" value="true" />
        <property name="testOnReturn" value="true" />
        <property name="testWhileIdle" value="true" />
        <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000" />
        <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="25200000" />
        <!-- 打开removeAbandoned功能 -->
        <property name="removeAbandoned" value="true" />
        <!-- 1800秒，也就是30分钟 -->
        <property name="removeAbandonedTimeout" value="1800" />
        <!-- 关闭abanded连接时输出错误日志 -->
        <property name="logAbandoned" value="true" />
        <!-- 监控数据库 -->
        <!-- <property name="filters" value="stat" /> -->
        <property name="filters" value="mergeStat" />
    </bean>

    <!-- 配置数据源 -->
    <bean name="dataSource1" init-method="init" destroy-method="close" parent="parentDatasource">
        <property name="url" value="${ds1.jdbc.url}" />
        <property name="username" value="${ds1.jdbc.username}" />
        <property name="password" value="${ds1.jdbc.password}" />
    </bean>


    <!-- 配置数据源 -->
    <bean name="dataSource2" init-method="init" destroy-method="close" parent="parentDatasource">
        <property name="url" value="${ds2.jdbc.url}" />
        <property name="username" value="${ds2.jdbc.username}" />
        <property name="password" value="${ds2.jdbc.password}" />
    </bean>

    <!-- 配置事务管理器 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource1" />
    </bean>

    <!-- 注解方式配置事物 -->
    <tx:annotation-driven transaction-manager="transactionManager" />

</beans>