Crud 项目介绍

简化单表的 CRUD 基本代码.

项目地址

https://github.com/huifer/crud/tree/dev

为什么使用

比如学生管理系统.表设计有课程表t_classes等等...在管理系统中我们需要添加课程的时候需要做一次 controller 、service 、redis 、dao 这几类操作. 每多一个表格都需要做这一批操作. 一般有新增、修改、删除、根据 id 查询.
- 当使用了这个项目后通过标记一些注解即可获得上述的功能.

假设现在有表格

| 字段 |类型 | | ---- | ---- | | id | int | | name | varchar |

常规实现

创建 controller 类
创建 service 类
创建一些验证方法
组合起来

@RestController
@RequestMapping("/demo")
public class ProjectDemoController {

  @Autowired
  private ProjectDemoMapper projectDemoMapper;

  @PostMapping("/add")
  public ResultVO add(
      @RequestBody ProjectDemo req
  ) {
    int i = projectDemoMapper.insertSelective(req);
    if (i > 0) {
      return ResultVO.success();
    }
    else {
      return ResultVO.failed();
    }
  }
}

省略验证方法, 省略 service 编写. 正常应该分一分.

现在只有数据库层面的交互代码我们可能还需要一个 redis 上的操作

(hash 数据类型) 那么这部分代码还需要在写一次

@RestController
@RequestMapping("/demo")
public class ProjectDemoController {

  @Autowired
  private ProjectDemoMapper projectDemoMapper;

  @Autowired
  private StringRedisTemplate stringRedisTemplate;

  @PostMapping("/add")
  public ResultVO add(
      @RequestBody ProjectDemo req
  ) {
    int i = projectDemoMapper.insertSelective(req);
    if (i > 0) {
      stringRedisTemplate.opsForHash()
          .put("demo", String.valueOf(req.getId()), JSON.toJSONString(req));
      return ResultVO.success();
    }
    else {
      return ResultVO.failed();
    }
  }
}

这部分代码出现的次数可能会随着实体类的增多而增多. 每当一个表出现上述的 CRUD 都需要在编辑以便代码. 很是繁琐，对此提出了一个设想.

crud 实现

省略 controller 的编写

路径说明: /rest+ @CrudController#uri + add\editor\del\byId
定义一个实体对象

@CrudController(uri = "/project/demo", idType = Integer.class)
public class ProjectInt extends AbsEntity implements Serializable {

  private String name;

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }
}

定义一个 mapper

@Mapper
@CacheKey(type = ProjectInt.class,key = "asdc")
public interface ProjectIntMapper extends A<Integer, ProjectInt> {

  @Override
  @Insert("INSERT INTO `project_int`(`name`) VALUES (#{name} ) ")
  @Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")
  int insertSelective(ProjectInt record);

  @Override
  @Select("select * from project_int where id = #{id,javaType=INTEGER} ")
  ProjectInt selectByPrimaryKey(@Param("id") Integer integer);

  @Override
  @Delete("DELETE FROM `dest`.`project_int` WHERE `id` = #{id} ")
  int deleteByPrimaryKey(@Param("id") Integer integer);

  @Override
  @Update("UPDATE `dest`.`project_int` SET `name` = #{name}  WHERE `id`= #{id}  ")
  int updateByPrimaryKeySelective(ProjectInt record);
}

@Bean
ServletRegistrationBean myServletRegistration() {
  ServletRegistrationBean srb = new ServletRegistrationBean();
  srb.setServlet(new OcaServlet());
  srb.setUrlMappings(Arrays.asList("/rest/*"));
  return srb;
}

权限验证:在使用了两个 servlet 后通过拦截器验证会有问题，请使用 filter 进行权限验证

自定义入参验证

自定义参数验证是不可避免的. 在这里提出一个接口com.github.huifer.crud.ctr.validated.ValidatedInterface
entityClass 填写对应的数据库对象即可

@Service
public class ProjectIntValidated implements ValidatedInterface<ProjectInt> {

  Gson gson = new Gson();


  public Class<?> entityClass() {
    return ProjectInt.class;
  }

  public void validateDelete(ProjectInt projectInt) {
    System.out.println(gson.toJson(projectInt));
  }

  public void validateAdd(ProjectInt projectInt) {
    System.out.println(gson.toJson(projectInt));
  }

  public void validateById(ProjectInt projectInt) {
    System.out.println(gson.toJson(projectInt));
  }

  public void validateEditor(ProjectInt projectInt) {
    System.out.println(gson.toJson(projectInt));
  }
}

如果验证不通过可以在这个方法中直接抛出异常.

省略 mybatis + redis 编写

有时我们需要直接调用普通的 crud 不需要从 controller 进行调用。在这个前提下我们可以使用
需要在 mapper 和 db 实体类进行标记


public class IssuesEntity implements BaseEntity {


  private Integer id;
  private String newTitle;
  private Date date;
 
}

@Mapper
@CacheKey(key = "issues", type = IssuesEntity.class)
public interface IssuesMapper extends A<Integer, IssuesEntity> {

  @Insert("   insert into issue(new_title)values(#{newTitle,jdbcType=VARCHAR})")
  @Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")
  int insertSelective(IssuesEntity record);

  @Select("select id as id , new_title as newTitle from issue where id = #{integer} ")
  IssuesEntity selectByPrimaryKey(Integer integer);

  @Override
  @Update("UPDATE `issue` SET `new_title` = #{newTitle}  WHERE `id` = #{id} ")
  int updateByPrimaryKeySelective(IssuesEntity record);

  @Override
  @Delete("delete from issue where id = #{integer}")
  int deleteByPrimaryKey(Integer integer);
}

调用层代码

  @Autowired
  private CrudFacade<IssuesEntity, IntIdInterface<Integer>> crudFacade;


 @Test
  void testInsert() {
    IssuesEntity issuesEntity = new IssuesEntity();
    issuesEntity.setNewTitle("mybatis_test");
    crudFacade.insert(issuesEntity);
  }

使用后直接具有 db 操作和 redis 的操作

省略 redis 编写

有时对象可能直接存储在 redis 中而不是存储 db 。在这个前提下可以使用
类标记

@CacheKey(key = "tt", type = IssuesEntity.class, idMethod = "ooo")
public class IssuesEntity implements BaseEntity {


  private Integer id;
  private String newTitle;
  private Date date;
}

调用层代码

@Autowired
private CrudEntityFacade<IssuesEntity> crudEntityFacade;

@Test
void testInsert() {
  IssuesEntity issuesEntity = new IssuesEntity();
  issuesEntity.setNewTitle("insert");
  issuesEntity.setDate(new Date());
  crudEntityFacade.insert(issuesEntity);
}

自定义 json 序列化规则

目前只支持 gson 和 jackjson 两种
- gson 自定实现: com.github.huifer.crud.common.conf.json.GsonConfigSetting
- jackjson 自定义实现: com.github.huifer.crud.common.conf.json.JackJsonConfigSetting
具体用例请查看: https://github.com/huifer/crud/tree/dev/simple-example