spring学习笔记九

数据源对象管理

1、加入pom坐标

        <dependency><groupId>com.alibaba</groupId><artifactId>druid</artifactId><version>1.1.16</version></dependency><!-- https://mvnrepository.com/artifact/c3p0/c3p0 --><dependency><groupId>c3p0</groupId><artifactId>c3p0</artifactId><version>0.9.1.2</version></dependency><!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>5.1.16</version></dependency>

2、jdbc.properties配置文件

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/spring_db
jdbc.username=root
jdbc.password=mima12341

3、spring配置文件

3.1、开启context命名空间

<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"  这里是新增xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/context  这里是新增http://www.springframework.org/schema/context/spring-context.xsd  这里是新增
">

3.2、完整配置文件 

<?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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsd
"><!--step1:    开启命名空间--><!--step2:    使用context空间加载properties文件--><context:property-placeholder location="jdbc.properties"/><bean id="datasource" class="com.alibaba.druid.pool.DruidDataSource"><property name="driverClassName" value="${jdbc.driver}" /><property name="url" value="${jdbc.url}" /><property name="username" value="${jdbc.username}" /><property name="password" value="${jdbc.password}" /></bean></beans>

4、使用方法

public static void main(String[] args) {ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");DataSource dataSource = (DataSource)ctx.getBean("datasource");System.out.println(dataSource);}

5、总结

• 3.1开启context命名空间
• 配置context:property-placeholder 设置location为配置文件名
• 配置datasource的Bean
• 使用${xxxx}获取配置文件中设置的值