mybatis

参考资料
mybatis
spring-mybatis
源码：git@code.aliyun.com:springmvc/simpleSpringMvc.git
mybatis分支

1、mybatis-spring引入

根据spring版本如果5以下，我们只能选择1.3版本。

<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis-spring</artifactId>
    <version>1.3.2</version>
</dependency>

2、mysql-connector-java引入

mysql-connector-java与mysql对应版本.png
mysql-connector-java与java对应版本.png
参考资料：
https://blog.csdn.net/lingeio/article/details/93487770
https://dev.mysql.com/doc/connector-j/5.1/en/connector-j-versions.html

整体pom依赖如下：

            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>8.0.17</version>
            </dependency>
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis-spring</artifactId>
                <version>1.3.0</version>
            </dependency>
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.4.0</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>1.1.20</version>
            </dependency>
          <dependency>
              <groupId>org.springframework</groupId>
             <artifactId>spring-jdbc</artifactId>
          </dependency>

Mapper建立：

public interface UserMapper {
    User selectUser1(String username);
}

Entity建立

@Data
public class User {
    private int id;
    private int age;
    private String name;
    private int type;
}

Service层接口

public interface UserService {
    User getUserByUsername(String username);
}

Service层实现

//供mapper使用
@Service("userService")
public class UserServiceImpl implements UserService {
    @Autowired
    private UserMapper userMapper;
    @Override
    public User getUserByUsername(String username) {
        User user = userMapper.selectUser1(username);
        return user;
    }
}

//使用sqlSessionTemplate
@Service("userService1")
public class UserService1Imp implements UserService {
    @Autowired
    private SqlSessionTemplate sqlSessionTemplate;

    @Override
    public User getUserByUsername(String username) {
        User user =sqlSessionTemplate.selectOne("com.jc.service.mysql.mapper.UserMapper.selectUser1",username);
        return user;
    }
}

Xml实现：

<?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.jc.service.mysql.mapper.UserMapper">
    <select id="selectUser1" parameterType="java.lang.String" resultType="com.jc.service.mysql.entity.User">
        select * from user where name=#{username}
    </select>
</mapper>

mybatis配置：

<!--使用MapperScannerConfigurer-->
<?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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                        http://www.springframework.org/schema/beans/spring-beans.xsd
                        http://www.springframework.org/schema/context
                        http://www.springframework.org/schema/context/spring-context.xsd">


    <context:property-placeholder location="classpath:config/jdbc.properties"/>
    <!-- 引入配置文件 -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close" init-method="init">
        <property name="driverClassName" value="${jdbc_driverClassName}"/>
        <property name="url" value="${jdbc_url}"/>
        <property name="username" value="${jdbc_username}"/>
        <property name="password" value="${jdbc_password}"/>
        <!-- 初始化连接大小 -->
        <property name="initialSize" value="${initialSize}"/>
        <!-- 连接池最大使用连接数量 -->
        <property name="maxActive" value="${maxActive}"/>
        <!-- 连接池最小空闲 -->
        <property name="minIdle" value="${minIdle}"/>
        <!-- 获取连接最大等待时间 -->
        <property name="maxWait" value="${maxWait}"/>
        <property name="validationQuery" value="${validationQuery}"/>
        <property name="testOnBorrow" value="false"/>
        <property name="testOnReturn" value="false"/>
        <property name="testWhileIdle" value="true"/>
        <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="10000"/>
        <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="25200000"/>
        <!-- 打开removeAbandoned功能 -->
        <property name="removeAbandoned" value="true"/>
        <!-- 1800秒，也就是30分钟 -->
        <property name="removeAbandonedTimeout" value="1800"/>
        <!-- 关闭abanded连接时输出错误日志 -->
        <property name="logAbandoned" value="true"/>
        <!-- 监控数据库 -->
        <!-- <property name="filters" value="stat" /> -->
        <property name="filters" value="mergeStat"/>
    </bean>


    <!-- myBatis文件 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <!-- 配置数据库表对应的java实体类，如果是非完全限定名，如返回参数User,而不是写成com.jc.service.mysql.entity.User,
         如果是完全限定，可省略-->
        <property name="typeAliasesPackage" value="com.jc.service.mysql.entity"/>
        <!-- 自动扫描entity目录, 省掉Configuration.xml里的手工配置 -->
        <property name="mapperLocations" value="classpath:mapper/*.xml"/>
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.jc.service.mysql.mapper"/>
        <!-- 如果仅有一个数据源，可省略 -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
    </bean>
</beans>

<!--使用SqlSessionTemplate,仅更改扫描-->
    <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg ref="sqlSessionFactory"/>
    </bean>