一.项目整体ssm框架展示:
1.在pom文件中加入mysql依赖:
mysql mysql-connector-java
2.添加lombok依赖注解式开发 《不用再写set,get方法》,减少代码量:
org.projectlombok lombok true
3.application.properties配置数据库连接:
server.port=8080
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/useruseUnicode=true&characterEncoding=utf8&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=root
#全局设置主键生成策略
mybatis-plus.global-config.db-config.id-type=auto
mybatis-plus.mapper-locations=classpath*:/mapper/**/*.xml
详情:
4.创建实体类entity:
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@Data
@TableName(“tb_teacher”)
public class Teacher {@TableId(value = "id",type = IdType.AUTO) private Integer id; private String tno; private String name; private char gender; private String password; private String email; private String telephone; private String address; private String clazzName; private String portraitPath;
}
5.测试使用mybatis-plus自带的增删查改方法;
添加pom依赖
com.baomidou mybatis-plus-boot-starter 3.2.0
6.TeacherMapper基础BaseMapper类
import com.atguigu.myzhxy.pojo.Teacher;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.springframework.stereotype.Repository;@Mapper
public interface TeacherMapper extends BaseMapper {
}
BaseMapper类里面封装了各式各样的增删查改方法,我们直接调用就OK了:
7.数据库添加表数据《表数据与实体类数据需要一一对应》
CREATE TABLE `tb_teacher` (
`id` int NOT NULL AUTO_INCREMENT,
`tno` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`name` varchar(15) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`gender` char(1) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`password` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`email` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`telephone` varchar(12) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`address` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`portrait_path` varchar(200) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`clazz_name` varchar(15) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
PRIMARY KEY (`id`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8mb3 ROW_FORMAT=DYNAMIC;
8.在测试类里面简单测试一下:
@Autowired
private TeacherMapper teacherMapper;
@Test
public void findAll(){
List<Teacher> teachers = teacherMapper.selectList(null);
System.out.println("查询所有数据"+teachers);
}
会看到我表里面的数据已经被全部查询出来了,mybatis-plus对于mybatis来说属于增强,去除了繁琐的写xml文件,各有各的优点,比如用plus就不能进行复杂查询,主要看自己的习惯吧,可以不喜欢但是一定一定要会了才有选择的权利;
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