Use ssm dao layer framework to develop the required profile (the applicationContext.xml) and jdbc.properties.

一、applicationContext.xml
<?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">
        <!--扫描包-->
        <context:component-scan base-package="cn.kgc.dao"></context:component-scan>
        <!--引入外部配置文件-->
        <context:property-placeholder location="the CLASSPATH: jdbc.properties "> </ context: Property-placeholder> 
        <- Create a data source ->!
        <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
            <property name="driverClass" value="${jdbc.driver}"></property>
            <property name="jdbcUrl" value="${jdbc.url}"></property>
            <property name="user" value="${jdbc.user}"></property>
            <property name="password" value="${jdbc.password}"></property>
        </bean>
</beans>

二、jdbc.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/group_project
jdbc.user=root
jdbc.password=ROOT