spring.xml从外部文件引入数据库配置信息

     <!-- 分散配置 -->
     <context:property-placeholder location="classpath:jdbc.properties" />

     <!-- 数据源 -->
     <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
         <property name="driverClass" value="${jdbc.driverclass}" />
         <property name="jdbcUrl" value="${jdbc.url}"></property>
         <property name="user" value="${jdbc.username}" />
         <property name="password" value="${jdbc.password}" />

         <property name="maxPoolSize" value="${c3p0.pool.size.max}" />
         <property name="minPoolSize" value="${c3p0.pool.size.min}" />
         <property name="initialPoolSize" value="${c3p0.pool.size.ini}" />
         <property name="acquireIncrement" value="${c3p0.pool.size.increment}" />
     </bean>

jdbc.properties

 jdbc.driverclass=com.mysql.jdbc.Driver
 jdbc.url=jdbc:mysql://localhost:3306/springmvcdb?characterEncoding=utf-8
 jdbc.username=root
 jdbc.password=root

 c3p0.pool.size.max=10
 c3p0.pool.size.min=2
 c3p0.pool.size.ini=3
 c3p0.pool.size.increment=2

 hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
 hibernate.show_sql=true

头

 <?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:mvc="http://www.springframework.org/schema/mvc"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:aop="http://www.springframework.org/schema/aop"
     xmlns:tx="http://www.springframework.org/schema/tx"
     xsi:schemaLocation="http://www.springframework.org/schema/beans
                         http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
                         http://www.springframework.org/schema/mvc
                         http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
                         http://www.springframework.org/schema/context
                         http://www.springframework.org/schema/context/spring-context-3.2.xsd
                         http://www.springframework.org/schema/aop
                         http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
                         http://www.springframework.org/schema/tx
                         http://www.springframework.org/schema/tx/spring-tx-3.2.xsd ">