Spring 中的事务

事务的ACID原则：

原子性：处于事务中的一切操作视为一个整体，不可分割,要么一起成功，要么一起失败

一致性：事务中的数据执行前后，状态一致，不会改变

隔离性：并发操作同一数据时，在前一个事务处理未提交之前，其他事务不会对该数据产生影响

持久性：一旦事务提交后，结果不可撤回

声明式事务：AOP，由容器来管理

编程式事务：在代码中处理事务

一.声明式事务：

1.pojo类

public class User {
    private int id;
    private String name;
    private int age;
    private String gradeid;

    public User(int id, String name, int age, String gradeid) {
        this.id = id;
        this.name = name;
        this.age = age;
        this.gradeid = gradeid;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getGradeid() {
        return gradeid;
    }

    public void setGradeid(String gradeid) {
        this.gradeid = gradeid;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", gradeid='" + gradeid + '\'' +
                '}';
    }
}

2.操作pojo类接口

public interface UserMapper {

    public List<User> selectUser();

    public int addUser(User user);

    public int deleteUser(@Param("id") int id);

}

3.UserMapper.xml编写，编写sql实体

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.ld.mapper.UserMapper">
    <select id="selectUser" resultType="aaa">
        select * from mysql_dong.cb_user;
    </select>

    <insert id="addUser" parameterType="aaa" >
        insert into mysql_dong.cb_user(id,name,age,gradeid) values (#{id},#{name},#{age},#{gradeid})
    </insert>

    <delete id="deleteUser" parameterType="int">
        delete from mysql_dong.cb_user where id = #{id}
    </delete>
</mapper>

4.编写接口实现类 UserMapperImpl.java 

public class UserMapperImpl extends SqlSessionDaoSupport implements UserMapper {



    public List<User> selectUser() {
        int a = addUser(new User(14,"沥青",13,"5"));
        System.out.println(a);
        deleteUser(12);
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }

    public int addUser(User user) {
        return getSqlSession().getMapper(UserMapper.class).addUser(user);
    }

    public int deleteUser(int id) {
        return getSqlSession().getMapper(UserMapper.class).deleteUser(id);
    }
}

5.编写mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">


<!--mybatis核心配置文件-->
<configuration>
    <typeAliases>
        <typeAlias type="com.ld.pojo.User" alias="aaa"/>
    </typeAliases>
</configuration>

6.mybatis-dao.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans
        xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">


    <!--    配置数据源-->
    <bean id="datasource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mysql_dong?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>

    </bean>

    <!--    sqlSessionFactory-->

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="datasource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:com/ld/mapper/*.xml"/>

    </bean>




</beans>

7.applicationContext.xml编写aop事务的植入

<?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:tx="http://www.springframework.org/schema/tx"
        xmlns:aop="http://www.springframework.org/schema/aop"
        xsi:schemaLocation="http://www.springframework.org/schema/beans

        http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">



    <import resource="spring-dao.xml"/>

    <bean id="userMapperImpl" class="com.ld.mapper.UserMapperImpl">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>


    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="datasource"/>
    </bean>

<!--    结合aop实现事务的植入-->
<!--    配置事务通知-->
    <tx:advice id="txadvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="add" propagation="REQUIRED"/>
            <tx:method name="query" read-only="true"/>
            <tx:method name="delete" propagation="REQUIRED"/>
            <tx:method name="update" propagation="REQUIRED"/>
            <tx:method name="selectUser" propagation="REQUIRED"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

<!--    配置事务的切入-->
    <aop:config>
        <aop:pointcut id="pointcut" expression="execution(* com.ld.mapper.*.*(..))"/>
        <aop:advisor advice-ref="txadvice" pointcut-ref="pointcut"/>
    </aop:config>

</beans>