Spring 入门之-dao使用jdbcTemplate（注入过程）

技巧：在为把dataSourc连接池注入到jdbcTemplate里面时，学到一招：按住CTRL 不松，点击相关类名，可以自动跳转或打开。

说明：主要过程，

1、创建UserDao和UserService类

2、在beans1配置文件中，创建注入连接池

<!-- 配置c3p0连接池 -->
     <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
         <property name="DriverClass" value ="com.mysql.jdbc.Driver"></property>
         <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/user"></property>
         <property name="user" value="root"></property>
         <property name="password" value="123456"></property>
     </bean>

3、在beans1.xml文件中，利用<bean id="" class="> 注入创建UserDao和UserService的类对象。并在UserService中,通过<property name="" ref="" >注入UserDao对象；在UserDao中注入jdbcTemplate对象

   <!-- 创建UserService 和UserDao对象，然后在UserService 中注入UserDao对象-->
     
     <bean id="userDao" class="spring.c3p0.UserDao">
     <!-- 注入jdbcTemplate对象 -->
         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
     </bean>
     
     
     <bean id="userService" class="spring.c3p0.UserService">
     <!-- 注入Dao对象 -->
        <property name="userDao"  ref="userDao"></property>    
     </bean>

4、把dataSourc连接池注入到jdbcTemplate里面

 <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate" >
         <!-- 把dataSourc连接池注入到jdbcTemplate里面 -->
         <property name="dataSource" ref="dataSource"></property>
     </bean>

TestC3p0.java文件代码：

package spring.c3p0;

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

public class TestC3p0 {
    @Test
    public void testDemo() {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans1.xml");
        UserService userService = (UserService) context.getBean("userService");
        userService.add();
    }

}

UserDao.java代码

package spring.c3p0;

import org.springframework.jdbc.core.JdbcTemplate;

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

    public void add() {
        // 测试用SQL
        String sql = "insert into users (name,age) values(?,?)";
        int rows = jdbcTemplate.update(sql,"american",299);
    }

}

UserService.java代码

package spring.c3p0;

public class UserService {
    private UserDao userDao;

    public void setUserDao(UserDao userDao) {
        this.userDao = userDao;
    }
    public void add() {
        userDao.add();
    }

}

beans1.xml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:aop="http://www.springframework.org/schema/aop"  
      xsi:schemaLocation="                                               
            http://www.springframework.org/schema/beans    
            http://www.springframework.org/schema/beans/spring-beans.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">
         <property name="DriverClass" value ="com.mysql.jdbc.Driver"></property>
         <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/user"></property>
         <property name="user" value="root"></property>
         <property name="password" value="123456"></property>
     </bean>
     <!-- 创建UserService 和UserDao对象，然后在UserService 中注入UserDao对象-->
     
     <bean id="userDao" class="spring.c3p0.UserDao">
     <!-- 注入jdbcTemplate对象 -->
         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
     </bean>
     
     
     <bean id="userService" class="spring.c3p0.UserService">
     <!-- 注入Dao对象 -->
        <property name="userDao"  ref="userDao"></property>    
     </bean>
     <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate" >
         <!-- 把dataSourc连接池注入到jdbcTemplate里面 -->
         <property name="dataSource" ref="dataSource"></property>
     </bean>
     
 </beans>