Spring4.0学习笔记(4) —— 使用外部属性文件

1、配置xml文件

<?xml version="1.0" encoding="UTF-8"?>
<beans
    xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

    <context:property-placeholder location="classpath:db.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>

2、外部配置文件

user=root
password=admin
driverclass=com.mysql.jdbc.Driver
jdbcUrl=jdbc:mysql:///authority

3、main方法

package com.spring.properties;

import java.sql.SQLException;

import javax.sql.DataSource;

import org.springframework.context.*;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {
    public static void main(String[] args) throws SQLException {
        ApplicationContext ctx = new ClassPathXmlApplicationContext("bean-properties.xml");

        DataSource dataSource = (DataSource)ctx.getBean("dataSource");
        System.out.println(dataSource.getConnection());
    }
}