SSM-Spring整合Mybatis[通俗易懂]

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步驟

1. 导入相关jar包
   • junit
   • mybatis
   • mysql数据库
   • spring相关的
   • aop植入
   • mybatis-spring[new]

<!--导入依赖-->
    <dependencies>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.46</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.4</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>
    </dependencies>

2. 编写配置文件
3. 测试

回忆Mybatis

1. 编写实体类

package com.kuang.pojo;

public class User { 
   
    private int id;
    private  String name;
    private String pwd;
    public User() { 
   
    }

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

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

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

    public void setPwd(String pwd) { 
   
        this.pwd = pwd;
    }

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

    public int getId() { 
   
        return id;
    }

    public String getName() { 
   
        return name;
    }

    public String getPwd() { 
   
        return pwd;
    }

}

2. 编写核心配置文件

<?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>
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

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

    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC" />
            <!-- 配置数据库连接信息 -->
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver" />
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8" />
                <property name="username" value="root" />
                <property name="password" value="924930871111" />
            </dataSource>
        </environment>
    </environments>
    <!--每一个Mapper.XML都需要在Mybatis核心核心配置文件中注册-->
    <mappers>
        <mapper class="com.kuang.mapper.UserMapper"/>
    </mappers>
</configuration>

3. 编写接口

package com.kuang.mapper;

import com.kuang.pojo.User;

import java.util.List;

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

4. 编写Mapper.xml文件

<?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">
<!--namespace绑定一个对应的Dao/Mapper接口-->
<mapper namespace="com.kuang.mapper.UserMapper">
    <select id="selectUser" resultType="user">
        select * from mybatis.user;
    </select>

</mapper>

5. 测试

import com.kuang.mapper.UserMapper;
import com.kuang.pojo.User;
import com.kuang.utils.MybatisUtils;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

public class Test { 
   
    public static void main(String[] args) { 
   
        return;
    }
    @org.junit.Test
    public void test() throws IOException { 
   
        String resources = "mybatis-config.xml";
        InputStream resourceAsStream = Resources.getResourceAsStream(resources);
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
        SqlSession sqlSession = sessionFactory.openSession(true);
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        List<User> userList = mapper.selectUser();
        for(User user:userList){ 
   
            System.out.println(user);
        }

    }
}

整合关键：Mybatis-Spring

方式1

整合步骤

1. 编写配置文件

<?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:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--DataSource:使用Spring的数据源替换Mybatis的配置 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=true&amp;useUnicode=true&amp;characterEncoding=UTF-8" />
        <property name="username" value="root"/>
        <property name="password" value="924930871111"/>

    </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/kuang/mapper/*.xml"/>
    </bean>
    <!--SqlSessionTemplate就是我们使用的SqlSession-->
    <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <!--只能使用构造器注入sqlSessionFactory,因为他没有set方法-->
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>

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

2. 需要给接口加实现类

package com.kuang.mapper;

import com.kuang.pojo.User;
import org.apache.ibatis.session.SqlSession;

import java.util.List;

public class UserMapperImpl implements UserMapper{ 
   
    private SqlSession sqlSession;

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

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

3. 将自己写的实现类，注入到Spring
   

4. 测试使用

import com.kuang.mapper.UserMapper;
import com.kuang.pojo.User;
import com.kuang.utils.MybatisUtils;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

public class Test { 
   
    public static void main(String[] args) { 
   
        return;
    }
    @org.junit.Test
    public void test() throws IOException { 
   
        ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
        UserMapper userMapper = context.getBean("userMapper", UserMapper.class);
        for(User user:userMapper.selectUser()){ 
   
            System.out.println(user);
        }
    }
}

方式二：利用继承类

不需要在Spring中注册SqlSession，只需要改动xml和测试类即可

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

package com.kuang.mapper;

import com.kuang.pojo.User;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

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

Spring事务管理

1. 声明式事务
2. 编程式事务

主要讲解声明式事务
思想是利用SpringAOP思想，通过配置文件的方式进行事务的管理
xml配置文件

    <!--配置声明式事务-->
    <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">
        <!--给那些方法配置事务-->
        <!--配置事务的传播特性：new propagation-->
        <tx:attributes>
            <tx:method name="add" propagation="REQUIRED"/>
            <tx:method name="update" propagation="REQUIRED"/>
            <tx:method name="delete" propagation="REQUIRED"/>
            <tx:method name="query" 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.kuang.mapper.*.*(..))"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txPointCut"/>
    </aop:config>

声明类

package com.kuang.mapper;

import com.kuang.pojo.User;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper { 
   
    public List<User> selectUser() { 
   
        User user = new User(5,"小王","12345");
        UserMapper mapper = getSqlSession().getMapper(UserMapper.class);
        mapper.addUser(user);
        mapper.deleteUser(5);
        return mapper.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);
    }
}

测试

import com.kuang.mapper.UserMapper;
import com.kuang.pojo.User;
import com.kuang.utils.MybatisUtils;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

public class Test { 
   
    public static void main(String[] args) { 
   
        return;
    }
    @org.junit.Test
    public void test() throws IOException { 
   
        ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
        UserMapper userMapper = context.getBean("userMapper2", UserMapper.class);
        for(User user:userMapper.selectUser()){ 
   
            System.out.println(user);
        }
    }
}