springboot+mybatis注解开发的增删改查

1.配置相关：

server.port=8080
spring.datasource.url=jdbc:mysql://localhost:3306/db_mybatis?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver



spring.jackson.date-format=yyyy-MM-dd HH:mm:ss
spring.jackson.time-zone=GMT+8

mybatis.type-aliases-package=cn.sjxy.springboot.mybatis_study.domain
mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.configuration.map-underscore-to-camel-case=true

2.主配置类

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

@EnableSwagger2
@MapperScan(value = {"cn.sjxy.springboot.mybatis_study.mapper"})
@SpringBootApplication
public class MybatisStudyApplication {

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

}

3.pom文件

  
        1.8
        2.0.3
        1.2.5
        3.3.9
        2.7.0
    

    
        
            org.springframework.boot
            spring-boot-starter-web
        

        
            org.springframework.boot
            spring-boot-starter-test
            test
        

        
            org.mybatis.spring.boot
            mybatis-spring-boot-starter
            2.0.1
        

        
        
            tk.mybatis
            mapper-spring-boot-starter
            ${mapper.starter.version}
        

        
        
            com.github.pagehelper
            pagehelper-spring-boot-starter
            ${pageHelper.starter.version}
        

        
        
            com.alibaba
            fastjson
            1.2.58
        

        
            mysql
            mysql-connector-java
            runtime
        
        
            org.projectlombok
            lombok
            true
        

        
        
            io.springfox
            springfox-swagger2
            2.7.0
        
        
            io.springfox
            springfox-swagger-ui
            2.7.0
        

        
        
            org.apache.httpcomponents
            httpclient
            4.5.9
        
        
        
            org.apache.httpcomponents
            httpcore
            4.4.11
        
    

    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
            
            
                org.apache.maven.plugins
                maven-surefire-plugin
                2.18.1
                
                    true
                
            
        
    

4.swagger2配置，综合我上一篇的swagger2进行配置
5.实体类
@Data可以自动生成get，set，tostring方法
需要安装一个插件

@ApiModel(“员工信息”)是对实体类的描述

@Data
@ApiModel("员工信息")
public class Employee {
    private int id;
    private String name;
    private Integer age;
    private int deptId;
    private Department department;
}

@Data
@ApiModel("部门信息")
public class Department {

    private int id;
    private String name;
    private List employee;


}

6.dao层编写

public interface EmployeeMapper {
//查询emp表所有信息，默认的结果集是 EMployee这个实体类
    @Select("select * from emp")
    List findAll();

//查询emp表中的所有信息，包括了员工对应的部门信息（多对一）
//使用one进行映射
    @Select("select * from emp")
    @Results(value = {
    //查询的主表是emp，需要查询的附属信息在dept表中，这里不能用外连接而是用查询的方法调用。
    //就是将emp表中与dept表中对应的字段作为参数传给findDept方法，column就是传的emp表中的字段
            @Result(property = "department", column = "dept_id",one = @One(select = "cn.sjxy.springboot.mybatis_study.mapper.DepartmentMapper.findDept"))
    })
    List findAllWithDept();


//查询一个员工的信息包括所在部门（一对一）
    @Select(" SELECT " +
            " * " +
            " FROM" +
            " emp" +
            " where" +
            " id = #{id} ")
    @Results(value = {
            @Result(property = "department", column = "dept_id", one = @One(select = "cn.sjxy.springboot.mybatis_study.mapper.DepartmentMapper.findDept"))
    })
    Employee findById(@Param("id") int id);

//通过部门编号查询员工
    @Select(" select " +
            " * " +
            " from " +
            " emp " +
            " where dept_id = #{dept_id}")
//    @Results(value = {
//            @Result(property = "department", column = "dept_id", one=@One(select = "cn.sjxy.springboot.mybatis_study.mapper.DepartmentMapper.findDept"))
//    })
    List findByDeptId(@Param("dept_id")int dept_id);

//通过编号删除员工
    @Delete("DELETE" +
            " FROM " +
            " emp " +
            " WHERE " +
            " id=#{id}")
    void deleteById(@Param("id") int id);

//插入员工
    @Insert(" INSERT " +
            " INTO " +
            " emp(name,age,dept_id) " +
            " VALUES(#{name}, #{age}, #{deptId}) ")
    void insert(Employee employee);

//更新员工信息
    @Update(" UPDATE " +
            " emp " +
            " SET name=#{name}, age = #{age} " +
            " WHERE " +
            " id = #{id}")
    void update(Employee employee);


}

public interface DepartmentMapper {

//通过部门id查询部门信息
    @Select(" select * from dept where id = #{id}")
    List findDept(@Param("id") int id);

//查询所有部门信息，包括部门下的员工信息（一对多）
    @Select(" select " +
            " * " +
            " from " +
            "dept")
    @Results(value = {
            @Result(property = "id", column = "id"),
            //查询的主表是dept，需要从emp表中取得相应的信息，就需要将dept对应于emp表的字段作为column的值传给方法findByDeptId
            @Result(property = "employee", column = "id",
                    many = @Many(select =
                            "cn.sjxy.springboot.mybatis_study.mapper.EmployeeMapper.findByDeptId"))
    })
    List findDeptWithEmp();
}

7.service层

@Service
public class DepartmentService {
    @Resource
    private DepartmentMapper departmentMapper;

   public List findDeptWithEmp(){
        return departmentMapper.findDeptWithEmp();
    }
}

 */
@Service
public class EmployeeService {
    @Resource
    EmployeeMapper employeeMapper;

    public List findAll(){
        System.out.println(employeeMapper.findByDeptId(1));
        return employeeMapper.findAll();
    }

    public List findAllWithDept(){
        return employeeMapper.findAllWithDept();
    }

    public Employee findById(int id){
        return employeeMapper.findById(id);
    }

    public void deleteById(int id){
        employeeMapper.deleteById(id);
    }

    public void update(Employee employee){
        employeeMapper.update(employee);
    }

    public void insert(Employee employee){
        employeeMapper.insert(employee);
    }
}

8.controller层

@RestController
@RequestMapping("/api/emp")
@Api(tags = "员工相关")
public class EmpController {
    @Resource
    private EmployeeService employeeService;

    @ApiOperation(value = "查询所有员工")
    @GetMapping("/findAll")
    public Result findAll(){
        return new Result<>(employeeService.findAll()) ;
    }

    @ApiOperation(value = "查询所有员工及其部门")
    @GetMapping("/findAllWithDept")
    public Result findAllWithDept(){
        return new Result<>(employeeService.findAllWithDept());
    }

    @ApiOperation(value = "查询员工信息")
    @ApiImplicitParam(paramType = "query", name = "id", dataType = "int", value = "用户id",required = true, defaultValue = "1")
    @GetMapping("/findById")
    public Result findById(@RequestParam("id")int id){
        return new Result(employeeService.findById(id));
    }

    @ApiOperation(value = "删除员工")
    @GetMapping("/deleteById")
    public void deleteById(@RequestParam("id")int id){
         employeeService.deleteById(id);
    }

    @ApiOperation(value = "修改员工")
    @GetMapping("/update")
    public void update(Employee employee){
        employeeService.update(employee);
    }

    @ApiOperation(value = "添加员工")
    @GetMapping("/insert")
    public void insert(Employee employee){
        employeeService.insert(employee);
    }
}

@RestController
@RequestMapping("/api/dept")
@Api(tags = "部门相关")
public class DepartmentController {
    @Resource
    private DepartmentService departmentService;

    @ApiOperation(value = "部门信息")
    @GetMapping("/findDeptWithEmp")
    public Result findDeptWithEmp(){
        return new Result<>(departmentService.findDeptWithEmp());
    }
}