spring（二） JDBC

一、配置 bean.xml , 链接数据库。

c3p0数据库连接池

 <?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"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:tx="http://www.springframework.org/schema/tx"
     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
         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">

     <!--注册类 -->
     <bean id="userDao" class="com.spring_jdbc.dao.UserDAO">
         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
     </bean>

     <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
         <property name="dataSource" ref="comboPooledDataSource"></property>
     </bean>

     <bean id="comboPooledDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
         <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
         <property name="jdbcUrl" value="jdbc:mysql:///spring"></property>
         <property name="user" value="root"></property>
         <property name="password" value="root"></property>
     </bean>

 </beans>

UserDAO.java

 package com.spring_jdbc.dao;
 import org.springframework.jdbc.core.JdbcTemplate;

 public class UserDAO {
     private JdbcTemplate jdbcTemplate;

     public JdbcTemplate getJdbcTemplate() {
         return jdbcTemplate;
     }
     public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }

     public void update(){
         //第四步:通过模板进行操作
         String str = "update t_user set money=money-1000 where username=?;";
         jdbcTemplate.update(str,"rose");
         System.out.println("操作成功。。。");
     }
 }
 /*
          //使用编码方式实现c3p0数据库连接池
     private ComboPooledDataSource dataSource;
     private JdbcTemplate jdbcTemplate;
     //第一步:创建连接池核心工具类
     ComboPooledDataSource dataSource = new ComboPooledDataSource();

     //第二步:连接池，url，驱动，账号，密码，初始连接数，最大连接数
     dataSource.setJdbcUrl("jdbc:mysql:///spring");//设置url
     dataSource.setDriverClass("com.mysql.jdbc.Driver");//设置驱动
     dataSource.setUser("root");//mysql的账号
     dataSource.setPassword("root");//mysql的密码

     //第三步:创建模板
     JdbcTemplate jdbcTemplate = new JdbcTemplate();
     jdbcTemplate.setDataSource(dataSource);

     //第四步:通过模板进行操作
     String str = "update t_user set money=money-1000 where username=?;";
     jdbcTemplate.update(str,"rose");
     System.out.println("操作成功。。。");
 */

service.java

 package com.spring_jdbc.dao;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;

 public class Service {

     public static void main(String[] args) throws Exception {
         ApplicationContext con = new ClassPathXmlApplicationContext("com/spring_jdbc/dao/UserDAO.xml");
         UserDAO userDao = (UserDAO)con.getBean("userDao");
         userDao.update();
     }
 }

事务管理

一、配置 bean.xml , 链接数据库，创建一个事务管理器。

c3p0数据库连接池

 <?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"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:tx="http://www.springframework.org/schema/tx" 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
         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">

     <!-- 初始化模板 -->
     <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
         <property name="dataSource" ref="comboPooledDataSource"></property>
     </bean>

     <!-- 创建数据源（连接池）    -->
     <bean id="comboPooledDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
         <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
         <property name="jdbcUrl" value="jdbc:mysql:///spring"></property>
         <property name="user" value="root"></property>
         <property name="password" value="root"></property>
     </bean>

     <bean id="service" class="com.spring_jdbc.transaction.Service">
         <property name="userDao" ref="userDao"></property>
     </bean>

     <!--注册类 -->
     <bean id="userDao" class="com.spring_jdbc.transaction.UserDAO">
         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
     </bean>

     <!-- 创建一个事务管理器 -->
     <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
         <property name="dataSource" ref="comboPooledDataSource"></property>
     </bean>

     <tx:advice id="txAdvice" transaction-manager="transactionManager">
         <tx:attributes>
             <tx:method name="change*" propagation="REQUIRED" isolation="DEFAULT"/>
         </tx:attributes>
     </tx:advice>

     <aop:config>
         <aop:advisor advice-ref="txAdvice" pointcut="execution(* com.spring_jdbc.transaction.*.*(..))" />
     </aop:config>

 </beans>

UserDAO.java

 package com.spring_jdbc.transaction;

 import org.springframework.jdbc.core.JdbcTemplate;

 public class UserDAO {

     private JdbcTemplate jdbcTemplate;

     public JdbcTemplate getJdbcTemplate() {
         return jdbcTemplate;
     }
     public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }

     public void update() throws Exception{

         //第四步:通过模板进行操作
         String str = "update t_user set money=money-1000 where username=?;";
         jdbcTemplate.update(str,"rose");
         System.out.println("操作成功。。。");

     }

     /**
      *  转账方
      * */
     public void money_less(){
         String str = "update t_user set money=money-? where username=?;";
         jdbcTemplate.update(str,1000,"rose");
         System.out.println("转出成功。。。");
     }
     /**
      *  接收方
      * */
     public void money_more(){
         String str = "update t_user set money=money+? where username=?;";
         jdbcTemplate.update(str,1000,"jack");
         System.out.println("接收成功。。。");
     }

 }

Service.java

 package com.spring_jdbc.transaction;

 public class Service {

     private UserDAO userDao;

     public UserDAO getUserDao() {
         return userDao;
     }
     public void setUserDao(UserDAO userDao) {
         this.userDao = userDao;
     }

     //    转账的实际操作
     public void changeAccount(){
         userDao.money_less();
 //        String s1 = null; //模拟异常。  事务回滚，数据不改变
 //        s1.charAt(0);
         userDao.money_more();
     }

 }

test.java

 package com.spring_jdbc.transaction;

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

 public class Action {
     public static void main(String[] args) {

         ApplicationContext con = new ClassPathXmlApplicationContext("com/spring_jdbc/transaction/UserDao.xml");
         Service service = (Service)con.getBean("service");
         service.changeAccount();

     }
 }