Java框架spring 學習筆記（十六）：c3p0鏈接池的配置以及dao使用jdbcTemplate

鏈接池能夠大大提升數據庫的性能和鏈接速度，將那些已鏈接的數據庫鏈接存放在一個鏈接池裏，之後別人要鏈接數據庫的時候，將不會從新創建數據庫鏈接，直接從鏈接池中取出可用的鏈接，用戶使用完畢後，會釋放鏈接從新放到鏈接池中。

 

下載必要jar包mchange-commons-java-0.2.14.jar和c3p0-0.9.2.1.jar

快捷鍵ctrl+alt+shift+s導入jar包

 

編寫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         //建立jdbcTemplate對象
12         //JdbcTemplate jdbcTemplate = new JdbcTemplate();
13         String sql = "insert into user values(?,?)"; 14         jdbcTemplate.update(sql,"Lilei","bbbbbb"); 15     }
16 }

 

編寫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 }

 

編寫配置文件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鏈接池 -->
18     <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
19         <!-- 注入dao對象 -->
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對象-->
31         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
32     </bean>
33 
34     <!-- 建立jdbcTemplate對象 -->
35     <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
36         <!-- 把dataSource傳遞到模板對象中-->
37         <property name="dataSource" ref="dataSource"></property>
38     </bean>
39 </beans>

 

編寫測試文件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 }

運行可見添加一條記錄