Spring配置C3P0、Druid数据源和JdbcTemplate模板类

外部配置参数：jdbc.properties
 

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql:///win668
jdbc.username=root
jdbc.password=root

Spring配置JdbcTemplate+c3p0数据源+Druid数据源

applicationContext.xml代码如下：

<?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">

    <!--导入外部数据源配置参数-->
    <context:property-placeholder location="jdbc.properties"/>

    <!--配置c3p0数据源-->
    <bean id="c3p0" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>

    <!--配置druid数据源-->
    <bean id="druid" 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>
    
    <!--配置tamplate模板-->
    <bean id="template" class="org.springframework.jdbc.core.JdbcTemplate">
        <constructor-arg name="dataSource" ref="druid"></constructor-arg>
    </bean>
</beans>

测试数据源

@Test
public void  testDruid(){
    ClassPathXmlApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
    DruidDataSource dataSource = app.getBean(DruidDataSource.class);
    String s = dataSource.toString();
    System.out.println(s);
}

@Test
public void  testC3P0(){
    ClassPathXmlApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
    ComboPooledDataSource dataSource = (ComboPooledDataSource) app.getBean("c3p0");
    System.out.println(dataSource);
}

测试模板类

@Test
public void  testJdbcTemplate(){
    //加载配置文件到Spring容器
    ClassPathXmlApplicationContext app = new ClassPathXmlApplicationContext("spring_jdbc.xml");
    //Spring容器通过JdbcTemplate.class 字节码创建 JdbcTemplate对象
    JdbcTemplate template = app.getBean(JdbcTemplate.class);
    //操作数据库
    String sql="select * from user where id<?";
    String sql1="select count(id) from user where id<?";
    Integer integer = template.queryForObject(sql1, Integer.class, 5);
    System.out.println(integer);
    List<User> list = template.query(sql, new BeanPropertyRowMapper<User>(User.class), 5);
    System.out.println(list);
    System.out.println(template);
}