SpringBoot整合mybatis

SpringBoot整合mybatis

添加依赖

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.15</version>
        </dependency>

        <!-- Mybatis -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>

        <!-- Mybatis 分页 -->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper</artifactId>
            <version>4.2.1</version>
        </dependency>

        <!-- Druid连接池包 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.1</version>
        </dependency>

配置数据库信息

在application.propertis或者application.yml配置文件中修改数据源配。

# 数据库访问配置
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8
spring.datasource.username=root
spring.datasource.password=123456

# 连接池的补充设置，应用到上面的数据源中
# 初始化大小，最小，最大
spring.datasource.initialSize=5
spring.datasource.minIdle=5
spring.datasource.maxActive=20
# 配置获取连接等待超时的时间
spring.datasource.maxWait=60000
# 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
spring.datasource.timeBetweenEvictionRunsMillis=60000
# 配置一个连接在池中最小生存的时间，单位是毫秒
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=SELECT 1 FROM DUAL
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
# 打开PSCache，并且指定每个连接上PSCache的大小
spring.datasource.poolPreparedStatements=true
spring.datasource.maxPoolPreparedStatementPerConnectionSize=20
# 配置监控统计拦截的filters，去掉后监控界面sql无法统计，‘wall‘用于防火墙
spring.datasource.filters=stat,wall,log4j
# 通过connectProperties属性来打开mergeSql功能；慢SQL记录
spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
# 合并多个DruidDataSource的监控数据
#spring.datasource.useGlobalDataSourceStat=true

#mybatis
#entity扫描的包名
mybatis.type-aliases-package=com.ldc.lab.model
#Mapper.xml所在的位置
mybatis.mapper-locations=classpath*:/mybaits/*Mapper.xml
#开启MyBatis的二级缓存
mybatis.configuration.cache-enabled=true

#pagehelper
pagehelper.helperDialect=mysql
pagehelper.reasonable=true
pagehelper.supportMethodsArguments=true
pagehelper.params=count=countSql

创建结构文件

编写实体类

public class Student {
    private  Integer  id;
    private  String  name;
    private  Integer  age;

    public Student(){ }
    //省略get set方法
}

编写接口

@Mapper
public interface UserMapper {
    // 数据层方法对象的sql映射，简单的sql可以以注解方式进行定义，复杂sql写到映射文件(xml)
    @Select("select * from stu")
    public List<Student>  selectStuList();
}

编写在resources文件中创建 mapper/UserMapper.xml文件

注意：

• namespace中需要与使用@Mapper的接口对应
• UserMapper.xml文件名称必须与使用@Mapper的接口一致
• 标签中的id必须与@Mapper的接口中的方法名一致，且参数一致

<?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.ldc.lab.mapper.UserMapper">
    <select id="selectStuList" resultType="Student">
        SELECT * FROM stu
    </select>
</mapper>

在启动类中添加对@MapperScan的扫描

@SpringBootApplication
@MapperScan(basePackages={"com.ldc.lab.mapper"})
public class LabApplication {

    public static void main(String[] args) {
        SpringApplication.run(LabApplication.class, args);
    }

}

测试

public class StudentDaoTests extends LabApplicationTests{
    @Autowired(required=false)
    private UserMapper userMapper;

    @Test
    public void testSelectObjects() {
        List<Student> stus = userMapper.selectStuList();
        for(Student stu:stus){
            System.out.println("name: " + stu.getName());
        }
    }
}

SpringBoot整合mybatis

原文：https://www.cnblogs.com/luedong/p/14604532.html