Spring通过c3p0配置bean连接数据库

<?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-4.3.xsd">
 
 
 <!-- 配置链接数据库 -->
 <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
 <property name="user" value="root"></property>
 <property name="password" value="wangjian"></property>
 <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
 <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=false"></property>
 </bean>
 
</beans>

<?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-4.3.xsd">
 
 <!-- 导入属性文件 -->
 
 <context:property-placeholder location="classpath:db.properties" />
 <!-- 使用外部化属性文件的属性 -->
 <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
 <property name="user" value="${user}"></property>
 <property name="password" value="${password}"></property>
 <property name="driverClass" value="${driverclass}"></property>
 <property name="jdbcUrl" value="${jdbcurl}"></property>
 </bean>
 
 
</beans>

user=root
password=wangjian
driverclass=com.mysql.jdbc.Driver
jdbcurl=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=false

package com.primary.spring.beans.properties;
 
import java.sql.SQLException;
 
import javax.sql.DataSource;
 
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
 
public class Main {
 public static void main(String[] args) throws SQLException {
 
 ApplicationContext ctx = new ClassPathXmlApplicationContext("beans-properties.xml");
 
 DataSource dataSource = (DataSource) ctx.getBean("dataSource");
 System.out.println(dataSource.getConnection());
 
 }
}