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

1 package com.jdbc.c3p0;
2 import org.springframework.jdbc.core.JdbcTemplate;
3
4 public class UserDao {
5     private JdbcTemplate jdbcTemplate;
6     public void setJdbcTemplate(JdbcTemplate jdbcTemplate){
7         this.jdbcTemplate = jdbcTemplate;
8     }
9
10     public void add(){
11         //创建jdbcTemplate对象
12         //JdbcTemplate jdbcTemplate = new JdbcTemplate();
13         String sql = "insert into user values(?,?)";
14         jdbcTemplate.update(sql,"Lilei","bbbbbb");
15     }
16 }

编写UserService.java

1 package com.jdbc.c3p0;
2
3 public class UserService {
4     private UserDao userDao;
5     public void setUserDao(UserDao userDao){
6         this.userDao = userDao;
7     }
8
9     public void add(){
10         userDao.add();
11     }
12 }

编写配置文件bean.xml

1 <?xml version="1.0" encoding="UTF-8"?>
2 <beans xmlns="http://www.springframework.org/schema/beans"
3        xmlns:tx="http://www.springframework.org/schema/tx"
4        xmlns:aop="http://www.springframework.org/schema/aop"
5        xmlns:context="http://www.springframework.org/schema/context"
6        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
7        xsi:schemaLocation="
8             http://www.springframework.org/schema/beans 9             http://www.springframework.org/schema/beans/spring-beans.xsd 10             http://www.springframework.org/schema/context 11             http://www.springframework.org/schema/context/spring-context.xsd 12             http://www.springframework.org/schema/tx 13             http://www.springframework.org/schema/tx/spring-tx.xsd 14             http://www.springframework.org/schema/aop 15             http://www.springframework.org/schema/aop/spring-aop.xsd ">
16
17     <!-- 配置c3p0连接池 -->
18     <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
19         <!-- 注入dao对象 -->
20         <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
21         <property name="jdbcUrl" value="jdbc:mysql:///test"></property>
22         <property name="user" value="root"></property>
23         <property name="password" value="xxxxx"></property>
24     </bean>
25
26     <bean id="userService" class="com.jdbc.c3p0.UserService">
27         <property name="userDao" ref="userDao"></property>
28     </bean>
29     <bean id="userDao" class="com.jdbc.c3p0.UserDao">
30         <!-- 注入jdbcTemplate对象-->
31         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
32     </bean>
33
34     <!-- 创建jdbcTemplate对象 -->
35     <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
36         <!-- 把dataSource传递到模板对象中-->
37         <property name="dataSource" ref="dataSource"></property>
38     </bean>
39 </beans>

编写测试文件TestService.java

1 package com.jdbc.c3p0;
2
3 import org.junit.Test;
4 import org.springframework.context.ApplicationContext;
5 import org.springframework.context.support.ClassPathXmlApplicationContext;
6
7 public class TestService {
8     @Test
9     public void testDemo(){
10         ApplicationContext context = new ClassPathXmlApplicationContext("bean.xml");
11         UserService userService = (UserService) context.getBean("userService");
12         userService.add();
13     }
14 }

运行可见添加一条记录