SpringMVC学习笔记三 整合jdbc和事务

spring整合JDBC

spring提供了很多模板整合Dao技术,用于简化编程。

 

引入相关jar包

 

spring中提供了一个可以操作数据库的对象,JDBCTemplate(JDBC模板对象)。对象封装了jdbc技术。与DBUtils中的QueryRunner非常相似。

@Test
public void fun1() throws Exception{
//0 准备连接池
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass("com.mysql.jdbc.Driver");
dataSource.setJdbcUrl("jdbc:mysql:///hibernate_32");
dataSource.setUser("root");
dataSource.setPassword("1234");
//1 创建JDBC模板对象
JdbcTemplate jt = new JdbcTemplate();
jt.setDataSource(dataSource);
//2 书写sql,并执行
String sql = "insert into t_user values(null,'rose') ";
jt.update(sql);

}

以上方式并没有用到spring容器,下面演示将连接池的配置交给 Spring 管理

1、dao接口,UserDao.java

package cn.itcast.a_jdbctemplate;

import java.util.List;

import cn.itcast.bean.User;

public interface UserDao {

    //
    void save(User u);
    //
    void delete(Integer id);
    //
    void update(User u);
    //
    User getById(Integer id);
    //
    int getTotalCount();
    //
    List<User> getAll();
}
View Code

2、dao实现类

package cn.itcast.a_jdbctemplate;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;

import cn.itcast.bean.User;
//使用JDBC模板实现增删改查
public class UserDaoImpl implements UserDao {
    private JdbcTemplate jt;
    @Override
    public void save(User u) {
        String sql = "insert into t_user values(null,?) ";
        jt.update(sql, u.getName());
    }
    @Override
    public void delete(Integer id) {
        String sql = "delete from t_user where id = ? ";
        jt.update(sql,id);
    }
    @Override
    public void update(User u) {
        String sql = "update t_user set name = ? where id=? ";
        jt.update(sql, u.getName(),u.getId());
    }
    @Override
    public User getById(Integer id) {
        String sql = "select * from t_user where id = ? ";
        return jt.queryForObject(sql,new RowMapper<User>(){
            @Override
            public User mapRow(ResultSet rs, int arg1) throws SQLException {
                User u = new User();
                u.setId(rs.getInt("id"));
                u.setName(rs.getString("name"));
                return u;
            }}, id);

    }
    @Override
    public int getTotalCount() {
        String sql = "select count(*) from t_user ";
        Integer count = jt.queryForObject(sql, Integer.class);
        return count;
    }

    @Override
    public List<User> getAll() {
        String sql = "select * from t_user ";
        List<User> list = jt.query(sql, new RowMapper<User>(){
            @Override
            public User mapRow(ResultSet rs, int arg1) throws SQLException {
                User u = new User();
                u.setId(rs.getInt("id"));
                u.setName(rs.getString("name"));
                return u;
            }});
        return list;
    }
  public void setJt(JdbcTemplate jt) {
  this.jt = jt;
  }
}

Spring配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">

<!-- 1.将连接池放入spring容器 -->
<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <property name="jdbcUrl" value="jdbc:mysql:///hibernate_crm"></property>
    <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
    <property name="user" value="root"></property>
    <property name="password" value="123456"></property>
</bean>


<!-- 2.将JDBCTemplate放入spring容器 -->
<bean name="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
    <property name="dataSource" ref="dataSource"></property>
</bean>

<!-- 3.将UserDao放入spring容器 -->
<bean name="userDao" class="cn.itcast.a_jdbctemplate.UserDaoImpl">
    <property name="jt" ref="jdbcTemplate"></property>
</bean>
</beans>

测试类:

package cn.itcast.a_jdbctemplate;

import java.beans.PropertyVetoException;

import javax.annotation.Resource;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import cn.itcast.bean.User;

//演示JDBC模板
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class Demo {
    @Resource(name="userDao")
    private UserDao ud;

    @Test
    public void fun2() throws Exception{
        User u = new User();
        u.setName("tom");
        ud.save(u);
    }
}
JDBCDaoSupport类简化了上面的操作,不需要自己手动创建JDBCTemplate类。使用方式如下:
//使用JDBC模板实现增删改查
public class UserDaoImpl extends JdbcDaoSupport implements UserDao {
    @Override
    public void save(User u) {
        String sql = "insert into t_user values(null,?) ";
        super.getJdbcTemplate().update(sql, u.getName());
    }
}

配置文件如下:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">

<!-- 指定spring读取db.properties配置 -->
<context:property-placeholder location="classpath:db.properties"/>

<!-- 1.将连接池放入spring容器 -->
<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <property name="jdbcUrl" value="jdbc:mysql:///hibernate_crm"></property>
    <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
    <property name="user" value="root"></property>
    <property name="password" value="123456"></property>
</bean>

<!-- 3.将UserDao放入spring容器 -->
<bean name="userDao" class="cn.itcast.a_jdbctemplate.UserDaoImpl">
    <property name="dataSource" ref="dataSource"></property>
</bean>
</beans>

读取外部的Properties配置

在db.properties中配置数据库连接信息,防止名称冲突,建议加前缀:

jdbc.jdbcUrl=jdbc:mysql:///hibernate_crm
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.user=root
jdbc.password=123456

配置文件:

<!-- 指定spring读取db.properties配置 -->
<context:property-placeholder location="classpath:db.properties" />

  <!-- 1.将连接池放入spring容器 -->
  <bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" >
  <property name="jdbcUrl" value="${jdbc.jdbcUrl}" ></property>
  <property name="driverClass" value="${jdbc.driverClass}" ></property>
  <property name="user" value="${jdbc.user}" ></property>
  <property name="password" value="${jdbc.password}" ></property>
</bean>

最终完整配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">

<!-- 指定spring读取db.properties配置 -->
<context:property-placeholder location="classpath:db.properties" />

<!-- 1.将连接池放入spring容器 -->
<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" >
<property name="jdbcUrl" value="${jdbc.jdbcUrl}" ></property>
<property name="driverClass" value="${jdbc.driverClass}" ></property>
<property name="user" value="${jdbc.user}" ></property>
<property name="password" value="${jdbc.password}" ></property>
</bean>


<!--&lt;!&ndash; 2.将JDBCTemplate放入spring容器 &ndash;&gt;-->
<!--<bean name="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate" >-->
<!--<property name="dataSource" ref="dataSource" ></property>-->
<!--</bean>-->

<!-- 3.将UserDao放入spring容器 -->
<bean name="userDao" class="cn.itcast.a_jdbctemplate.UserDaoImpl" >
<!-- <property name="jt" ref="jdbcTemplate" ></property> -->
<property name="dataSource" ref="dataSource" ></property>
</bean>
</beans>

spring中aop事务

spring封装了事务管理代码,因为在不同平台,操作事务的代码各不相同,spring提供了一个 PlatformTransactionManager 接口。

注意:在spring中玩事务管理.最为核心的对象就是TransactionManager对象

spring管理事务的属性介绍

1、事务的隔离级别

  • 1 读未提交
  • 2 读已提交
  • 4 可重复读
  • 8 串行化

2、是否只读

  • true 只读
  • false 可操作

3、事务的传播行为

spring管理事务方式

测试环境搭建

package com.yyb.dao;

public interface AccountDao {
    //加钱
    void increaseMoney(Integer id, Double money);
    //减钱
    void decreaseMoney(Integer id, Double money);
}
AccountDao
package com.yyb.dao;

import org.springframework.jdbc.core.support.JdbcDaoSupport;

public class AccountDaoImpl extends JdbcDaoSupport implements AccountDao  {
    @Override
    public void increaseMoney(Integer id, Double money) {
        getJdbcTemplate().update("update t_account set money = money+? where id = ? ", money,id);
    }
    @Override
    public void decreaseMoney(Integer id, Double money) {
        getJdbcTemplate().update("update t_account set money = money-? where id = ? ", money,id);
    }

}
AccountDaoImpl
package com.yyb.service;

public interface AccountService {
    //转账方法
    void transfer(Integer from, Integer to, Double money);
}
AccountService
package com.yyb.service;

import com.yyb.dao.AccountDao;


public class AccountServiceImpl implements AccountService {
    private AccountDao ad;

    @Override
    public void transfer(Integer from, Integer to, Double money) {
        //减钱
        ad.decreaseMoney(from,money);
        //加钱
        ad.increaseMoney(to,money);
    }

    public void setAd(AccountDao ad) {
        this.ad = ad;
    }
}
AccountServiceImpl
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd ">

    <!-- 指定spring读取db.properties配置 -->
    <context:property-placeholder location="classpath:db.properties"/>
    <!-- 1.连接池 -->
    <bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
    </bean>
    <!-- 2.Dao-->
    <bean name="accountDao" class="com.yyb.dao.AccountDaoImpl">
        <property name="dataSource" ref="dataSource"></property>
    </bean>
    <!-- 3.Service-->
    <bean name="accountService" class="com.yyb.service.AccountServiceImpl">
        <property name="ad" ref="accountDao"></property>
    </bean>

</beans>
applicationContext
jdbc.jdbcUrl=jdbc:mysql:///hibernate_crm
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.user=root
jdbc.password=123456
db.properties
package com.yyb.app;

import com.yyb.service.AccountService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

/**
 * Created by Administrator on 2017/8/17.
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class TransactionTest {
    @Autowired
   private AccountService accountService;
    @Test
    public void func1(){
        accountService.transfer(1,2,100d);
    }

}
TransactionTest

方式1:编码式(了解)

1.将核心事务管理器配置到spring容器,在applicationContext中配置如下代码:

    <!-- 事务核心管理器,封装了所有事务操作. 依赖于连接池 -->
    <bean name="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

2.配置TransactionTemplate模板,在applicationContext中配置如下代码:

   <!--事务模板对象-->
    <bean class="org.springframework.transaction.support.TransactionTemplate">
        <property name="transactionManager" ref="transactionManager"></property>
    </bean>

3.将事务模板注入Service

    <!-- 3.Service-->
    <bean name="accountService" class="com.yyb.service.AccountServiceImpl">
        <property name="ad" ref="accountDao"></property>
        <property name="tt" ref="transactionTemplate"></property>
    </bean>

4.在Service中调用模板

package com.yyb.service;

import com.yyb.dao.AccountDao;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallbackWithoutResult;
import org.springframework.transaction.support.TransactionTemplate;


public class AccountServiceImpl implements AccountService {
    private AccountDao ad;
    private TransactionTemplate tt;

    //匿名内部类访问外部变量得加final
    @Override
    public void transfer(final Integer from,final Integer to, Double money) {
        tt.execute(new TransactionCallbackWithoutResult() {
            @Override
            protected void doInTransactionWithoutResult(TransactionStatus transactionStatus) {
                //减钱
                ad.decreaseMoney(from,money);
                //int i=1/0;
                //加钱
                ad.increaseMoney(to,money);
            }
        });
    }

    public void setAd(AccountDao ad) {
        this.ad = ad;
    }
    public void setTt(TransactionTemplate tt) {
        this.tt = tt;
    }
}

方式2:xml配置(aop)

简单理解就是把通知织入到目标对象中,形成一个代理对象。比如通知要进行事务管理,目标对象要进行业务处理。那么代理对象则把事务管理和业务处理合到了一起。SpringAOP给我们准备了一个事务通知,目标对象即我们的service。所以只需要配置一下就可以了。

 1、需要导包aop、aspect、aop联盟、weaving织入包

2.导入新的约束(tx)

 

beans: 最基本约束;context:读取properties配置约束;aop:配置aop约束;tx:配置事务通知约束

3.配置通知和配置将通知织入目标

<!-- 事务核心管理器,封装了所有事务操作. 依赖于连接池 -->
    <bean name="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"></property>
    </bean>
    <!-- 配置事务通知 -->
    <tx:advice id="txAdvice" transaction-manager="transactionManager" >
        <tx:attributes>
            <!-- 以方法为单位,指定方法应用什么事务属性
                isolation:隔离级别
                propagation:传播行为
                read-only:是否只读
             -->
            <tx:method name="transfer" isolation="DEFAULT" propagation="REQUIRED" read-only="false"/>
            <!--上面的方式只适用单个方法,当我们业务有很多个方法都要操作事务时,则要配置很多个,可以使用下面的通配符配置方式-->
            <tx:method name="save*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />
            <tx:method name="persist*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />
            <tx:method name="update*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />
            <tx:method name="modify*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />
            <tx:method name="delete*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />
            <tx:method name="remove*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />
            <tx:method name="get*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="true" />
            <tx:method name="find*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="true" />
        </tx:attributes>
    </tx:advice>
    <!--配置织入-->
    <aop:config>
        <aop:pointcut id="txPc" expression="execution(* com.yyb.service.*ServiceImpl.*(..))"/>
        <!--配置切面-->
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPc"/>
    </aop:config>

方式3:注解配置(aop)

1.导包(同上)

2.导入新的约束(tx),同上

3.开启注解管理事务

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd ">

    <!-- 指定spring读取db.properties配置 -->
    <context:property-placeholder location="classpath:db.properties"/>

    <!-- 事务核心管理器,封装了所有事务操作. 依赖于连接池 -->
    <bean name="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"></property>
    </bean>
    <!--开启使用注解管理aop事务-->
    <tx:annotation-driven/>
    <!-- 1.连接池 -->
    <bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
    </bean>
    <!-- 2.Dao-->
    <bean name="accountDao" class="com.yyb.dao.AccountDaoImpl">
        <property name="dataSource" ref="dataSource"></property>
    </bean>
    <!-- 3.Service-->
    <bean name="accountService" class="com.yyb.service.AccountServiceImpl">
        <property name="ad" ref="accountDao"></property>
    </bean>

</beans>

4.使用注解

    @Transactional(isolation = Isolation.REPEATABLE_READ,propagation = Propagation.REQUIRED,readOnly = false)
    public void transfer(Integer from,Integer to, Double money) {

在方法上加注解,如果方法太多,嫌麻烦的话,可以在类上加,如果某个方法不适应,再在方法上写一份即可。

package com.yyb.service;

import com.yyb.dao.AccountDao;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

@Transactional(isolation = Isolation.REPEATABLE_READ,propagation = Propagation.REQUIRED,readOnly = false)
public class AccountServiceImpl implements AccountService {
    private AccountDao ad;

    @Override
    @Transactional(isolation = Isolation.DEFAULT,propagation = Propagation.REQUIRED,readOnly = false)
    public void transfer(Integer from,Integer to, Double money) {
        //减钱
        ad.decreaseMoney(from,money);
        //int i=1/0;
        //加钱
        ad.increaseMoney(to,money);
    }

    public void setAd(AccountDao ad) {
        this.ad = ad;
    }

}

 更详细请参考:

http://www.mamicode.com/info-detail-1248286.html

http://www.cnblogs.com/yepei/p/4716112.html

posted @ 2017-08-14 13:49  ~冰  阅读(1024)  评论(0编辑  收藏  举报