个人java学习路线-整合Spring和mybatis

Spring整合Mybatis步骤

1.导入相关jar包

• junit
• mybatis
• mysql数据库
• spring相关
• aop织入
• mybatis-spring【new这里讲】

pom.xml中需导入的包:

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.3.9</version>
        </dependency>
        <!-- Spring操作数据库的话，还需要一个spring-jdbc-->
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.9</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.6</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis-spring -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.6</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>
    </dependencies>

2.原来的mybatis编写配置文件测试(可略)

编写db.properties：

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/mybatis?useSSL=false&useUnicode=true&characterEncoding=UTF-8
username=root
password=123
//高版本mysql换useSSL=true

实体类：

@Data
public class User {
    
    
    private Integer id;
    private String name;
    private String pwd;
}

UserMapper接口：

public interface UserMapper {
    
    
    List<User> selectUser();
}

UserMapper.xml:

<?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.person.mapper.UserMapper">
    
    <select id="selectUser" resultType="user">
        select * from user;
    </select>
</mapper>

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">
<configuration>
    <properties resource="db.properties" />
    <typeAliases>
        <package name="com.person.pojo"/>
    </typeAliases>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <package name="com.person.mapper"/>
    </mappers>
</configuration>

DBUtil类：

public class DBUtil {
    
    
    private static SqlSessionFactory sqlSessionFactory;
    static {
    
    
        try {
    
    
            String resource="mybatis-config.xml";
            InputStream inputStream= Resources.getResourceAsStream(resource);
            sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
    
    
            e.printStackTrace();
        }
    }
    public static SqlSession getSqlSession(){
    
    
        return sqlSessionFactory.openSession();
    }
}

测试代码:

    @Test
    public void selectUser() {
    
    
        SqlSession sqlSession= DBUtil.getSqlSession();
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
        List<User> userList = userMapper.selectUser();
        for (User user:userList){
    
    
            System.out.println(user);
        }
        sqlSession.close();
    }

3.Spring整合mybatis代码步骤

1.编写数据源配置
2.sqlSessionFactory
3.sqlSessionTemplate
4.需要给接口加实现类【】
5.将自己写的实现类，注入到Spring中
6.测试使用

1.编写数据源配置
实体类：

@Data
public class User {
    
    
    private Integer id;
    private String name;
    private String pwd;
}

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">
<configuration>

    <typeAliases>
        <package name="com.person.pojo"/>
    </typeAliases>
</configuration>

UserMapper接口：

public interface UserMapper {
    
    
    List<User> selectUser();
}

UserMapper.xml:

<?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.person.mapper.UserMapper">
    
    <select id="selectUser" resultType="user">
        select * from user;
    </select>
</mapper>

2.UserMapper实现类：

public class UserMapperImpl implements UserMapper {
    
    

    //我们的所有操作，都使用sqlSession来执行，在原来，现在都是用SqlSessionTemplate
    private SqlSessionTemplate sqlSession;

    public void setSqlSession(SqlSessionTemplate sqlSession) {
    
    
        this.sqlSession = sqlSession;
    }

    public List<User> selectUser() {
    
    
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        return mapper.selectUser();
    }
}

3.spring-dao配置(整合配置)
spring-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.xsd">

    <!--
        DataSource:使用Spring的数据源替换Mybatis的配置(其它还有c3p0 dbcp druid)
        我们这里使用Spring提供的JDBC
    -->
    <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/mybatis?useSSL=false&amp;useUnicode=true&amp;characterEncoding=UTF-8" />
        <property name="username" value="root" />
        <property name="password" value="888666" />
    </bean>

    <!--sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <!--绑定Mybatis配置文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml" />
        <property name="mapperLocations" value="classpath:com/person/mapper/UserMapper.xml" />
    </bean>

    <!--SqlSessionTemplate:就是我们使用的sqlSession--><!--用方法二UserMapperImpl2时，这个也可以省略-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate" >
        <!--只能使用构造器注入，因为没有set方法-->
        <constructor-arg index="0" ref="sqlSessionFactory" />
    </bean>

    <!-- -->
    <bean id="userMapper" class="com.person.mapper.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession"/>
    </bean>
</beans>

4.测试代码：

@Test
public void selectUser() {
    
    

    ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
    UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
    for (User user : userMapper.selectUser()) {
    
    
        System.out.println(user);
    }
}

4.Spring整合mybatis第二种方法

上面1.编写数据源配置不变
2.UserMapper实现类：

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper{
    
    
    public List<User> selectUser() {
    
    
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }
}

3.spring-dao.xml不变
新建文件applicationContext.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.xsd">

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

    <bean id="userMapper2" class="com.person.mapper.UserMapperImpl2">
        <property name="sqlSessionFactory" ref="sqlSessionFactory" />
    </bean>
</beans>

4.测试代码：

@Test
public void selectUser2() {
    
    
    ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
    UserMapper userMapper = context.getBean("userMapper2", UserMapper.class);
    for (User user : userMapper.selectUser()) {
    
    
        System.out.println(user);
    }
}

事务

回顾事务

事务的ACID原则

• 原子性
• 一致性
• 隔离性

多个业务可能操作同一个资源，防止数据损坏

• 持久性

事务一旦提交，无论系统发生什么问题，结果都不会再被影响，被持久化的写到存储器中！

mybatis-spring的事务

mybatis-spring借助了Spring的DataSourceTransactionManager来实现事务管理
事务分为：
声明式事务：AOP【主要】
编程式事务:需要在代码中间，进行事务的管理

代码实例

实体类：

@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
    
    
    private Integer id;
    private String name;
    private String pwd;
}

UserMapper接口

public interface UserMapper {
    
    
    List<User> selectUser();
    
    //添加一个用户
    int addUser(User user);

    //删除一个用户
    int deleteUser(int id);

    //事务测试
    int transaction(User user,int id);
}

UserMapper.xml

<?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.person.mapper.UserMapper">
    
    <select id="selectUser" resultType="user">
        select * from user;
    </select>

    <insert id="addUser" parameterType="user">
        insert into user (name,pwd) values (#{name},#{pwd});
    </insert>

    <delete id="deleteUser" parameterType="int">
        delete from user where id=#{id};
    </delete>
</mapper>

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">
<configuration>

    <typeAliases>
        <package name="com.person.pojo"/>
    </typeAliases>

</configuration>

UserMapperImpl类

public class UserMapperImpl extends SqlSessionDaoSupport implements UserMapper{
    
    
    public List<User> selectUser() {
    
    
        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);
    }

    public int transaction(User user,int id) {
    
    
        getSqlSession().getMapper(UserMapper.class).addUser(user);
        getSqlSession().getMapper(UserMapper.class).deleteUser(id);
        return 1;
    }
}

spring-dao.xml(事务配置)

<?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: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/tx
                           http://www.springframework.org/schema/tx/spring-tx.xsd">

    <!--
        DataSource:使用Spring的数据源替换Mybatis的配置(其它还有c3p0 dbcp druid)
        我们这里使用Spring提供的JDBC
    -->
    <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/mybatis?useSSL=false&amp;useUnicode=true&amp;characterEncoding=UTF-8" />
        <property name="username" value="root" />
        <property name="password" value="888666" />
    </bean>

    <!--sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <!--绑定Mybatis配置文件-->
        <!--
            value="classpath:mybatis-config.xml"  不能有空格
        -->
        <property name="configLocation" value="classpath:mybatis-config.xml" />
        <property name="mapperLocations" value="classpath:com/person/mapper/UserMapper.xml" />
    </bean>

    <!--配置声明式事务-->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <constructor-arg ref="dataSource"/>
        <!--<property name="dataSource" ref="dataSource"/>-->
    </bean>

    <!--结合AOP实现事务的织入-->
    <!--配置事务通知-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <!--给哪些方法配置事务-->
        <!--配置事务的传播特性:  new propagation 默认REQUIRED -->
        <!--name得和方法名一致-->
        <tx:attributes>
            <tx:method name="add" propagation="REQUIRED"/>
            <tx:method name="delete" propagation="REQUIRED"/>
            <tx:method name="update" propagation="REQUIRED"/>
            <tx:method name="query" read-only="true"/>
            <tx:method name="transaction" propagation="REQUIRED"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <!--配置事务切入-->
    <aop:config>
        <aop:pointcut id="txPointCut" expression="execution(* com.person.mapper.*.*(..))"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPointCut" />
    </aop:config>
</beans>

applicationContext.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"
       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">

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

    <!--bean-->
    <bean id="userMapper" class="com.person.mapper.UserMapperImpl">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>
</beans>

测试代码：

    @Test
    public void selectUser() {
    
    
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
        for (User user : userMapper.selectUser()) {
    
    
            System.out.println(user);
        }
    }