user=root

password=123

driverClass=com.mysql.jdbc.Driver

jdbcUrl=jdbc\:mysql\:///test

<?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">

<!-- 导入外部配置文件-->

<context:property-placeholder location="classpath:jdbc.properties"/>

<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>

package spring.beans.properties.test;

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());

    }

}

com.mchange.v2.c3p0.impl.NewProxyConnection@28ac3dc3