idea2023 springboot2.7.5+mybatisplus3.5.2+jsp 初学单表增删改查

创建项目

修改pom.xml 为2.7.5
引入mybatisplus
2.1 修改pom.xml

<dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.2</version>
        </dependency>

        <!--mysql驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.29</version>
        </dependency>

        <!--C标签库得使用-->
        <dependency>
            <groupId>jstl</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

        <!--如下是为了配置，可以正常访问jsp-->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>

2.2 修改application.properties 如下内容：

server.port=8081
spring.datasource.url=jdbc:mysql://localhost:3306/jdbc08
spring.datasource.username=root
spring.datasource.password=
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
mybatis.mapper-locations=classpath:mapper/*.xml

2.3src下的实体类
配置表名
配置主键

@Data
@TableName("tb_dept")
public class DeptBean implements Serializable {
    @TableId(value = "did", type = IdType.ASSIGN_ID)
    private int did;
    private String dname;

}

2.4 src下的mapper

@Mapper
public interface DeptMapper extends BaseMapper<DeptBean> {

}

2.5 src下的service

@Service
public class DeptService {

    @Autowired
    private DeptMapper deptMapper;

    public void addDeptService(DeptBean name){
        deptMapper.insert(name);
    }

    public void delDeptService(int did){
        deptMapper.deleteById(did);
    }

    public void updateDeptService(DeptBean deptBean){
        deptMapper.updateById(deptBean);
    }

    public DeptBean byidDeptService(int did){
        return deptMapper.selectById(did);
    }

    public List<DeptBean> allDeptService(){
        return deptMapper.selectList(null);
    }

}

2.6 src下的controller

@Controller
public class DeptController {
    @Autowired
    private DeptService deptService;



    @RequestMapping("addDept")
    public String addDept(DeptBean dname){
        deptService.addDeptService(dname);
        return "allDept";
    }

    @RequestMapping("allDept")
    public String allDept(Model model){
        model.addAttribute("alldept",deptService.allDeptService());
        return "deptAll.jsp";
    }

    @RequestMapping("byidDept")
    public String byidDept(int id ,Model model){
        System.out.println(id);
        model.addAttribute("byidDept",deptService.byidDeptService(id));
        return "deptUpdate.jsp";
    }

    @RequestMapping("delDept")
    public String delDept(int id){
        deptService.delDeptService(id);
        return "allDept";
    }

    @RequestMapping("updateDept")
    public String updateDept(DeptBean deptBean){
        deptService.updateDeptService(deptBean);
        return "allDept";
    }
}