Java框架spring 学习笔记（十六）：c3p0连接池的配置以及dao使用jdbcTemplate

连接池可以大大提高数据库的性能和连接速度，将那些已连接的数据库连接存放在一个连接池里，以后别人要连接数据库的时候，将不会重新建立数据库连接，直接从连接池中取出可用的连接，用户使用完毕后，会释放连接重新放到连接池中。

下载必要jar包mchange-commons-java-0.2.14.jar和c3p0-0.9.2.1.jar

快捷键ctrl+alt+shift+s导入jar包

编写UserDao.java

package com.jdbc.c3p0;
import org.springframework.jdbc.core.JdbcTemplate;

public class UserDao {
    private JdbcTemplate jdbcTemplate;
    public void setJdbcTemplate(JdbcTemplate jdbcTemplate){
        this.jdbcTemplate = jdbcTemplate;
    }

    public void add(){
        //创建jdbcTemplate对象
        //JdbcTemplate jdbcTemplate = new JdbcTemplate();
        String sql = "insert into user values(?,?)";
        jdbcTemplate.update(sql,"Lilei","bbbbbb");
    }
}

编写UserService.java

package com.jdbc.c3p0;

public class UserService {
    private UserDao userDao;
    public void setUserDao(UserDao userDao){
        this.userDao = userDao;
    }

    public void add(){
        userDao.add();
    }
}

编写配置文件bean.xml

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

    <!-- 配置c3p0连接池 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!-- 注入dao对象 -->
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql:///test"></property>
        <property name="user" value="root"></property>
        <property name="password" value="xxxxx"></property>
    </bean>

    <bean id="userService" class="com.jdbc.c3p0.UserService">
        <property name="userDao" ref="userDao"></property>
    </bean>
    <bean id="userDao" class="com.jdbc.c3p0.UserDao">
        <!-- 注入jdbcTemplate对象-->
        <property name="jdbcTemplate" ref="jdbcTemplate"></property>
    </bean>

    <!-- 创建jdbcTemplate对象 -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!-- 把dataSource传递到模板对象中-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>
</beans>

编写测试文件TestService.java

package com.jdbc.c3p0;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class TestService {
    @Test
    public void testDemo(){
        ApplicationContext context = new ClassPathXmlApplicationContext("bean.xml");
        UserService userService = (UserService) context.getBean("userService");
        userService.add();
    }
}

运行可见添加一条记录