zoukankan      html  css  js  c++  java
  • 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

  • 相关阅读:
    创建user keywords
    robotframework中list和dict variables
    安装sshlibrary库报错:Could not find a version that satisfies the requirement
    【转】用U盘制作启动盘后空间变小的恢复方法
    docker "exec format error"
    window cmd 设置IP,关闭防火墙,开启远程桌面
    Linux iptables
    python logging 模块
    docker 命令
    python xmlrpc入门
  • 原文地址:https://www.cnblogs.com/ginb/p/7357388.html
Copyright © 2011-2022 走看看