• 😜作           者：是江迪呀
• ✒️本文关键词：SpringBoot、模版、企业级
• ☀️每日   一言：你坚持下来了，而别人坚持不下来，这就是你的资本。

上回我们创建了一个SpringBoot项目并且连接了数据库整合了MyBatis-plus框架。今天我们来添加一些公共的东西如：全局异常配置、返回体配置。

本次需要的依赖：

<dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.16.16</version>
</dependency>
<dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.75</version>
</dependency>

本节最终项目结构：

一、全局异常配置

在一个项目中我们常常需要处理一些业务异常，自定义一些状态码，SpringBoot框架中也有对应的方法供我们使用，但是为方便后续的扩展我们还是要自定义一个全局异常。

1.1 全局异常处理

@ControllerAdvice
@Slf4j
public class GlobalExceptionHandler {@ExceptionHandler(value = BusinessException.class)@ResponseBodypublic Response businessExceptionHandler(HttpServletRequest request, BusinessException e){log.error("发生业务异常！原因是：{}",e.getErrorMsg());return Response.error(e.getErrorCode(),e.getErrorMsg());}/*** 处理空指针的异常* @param req* @param e* @return*/@ExceptionHandler(value =NullPointerException.class)@ResponseBodypublic Response exceptionHandler(HttpServletRequest req, NullPointerException e){log.error("发生空指针异常！原因是:",e);return Response.error(ResultEnum.BIZ_EXCEPTION.getValue());}/*** 处理其他异常* @param req* @param e* @return*/@ExceptionHandler(value =Exception.class)@ResponseBodypublic Response exceptionHandler(HttpServletRequest req, Exception e){log.error("系统异常！原因是:",e);return Response.error(ResultEnum.BIZ_EXCEPTION.getValue());}
}

• @ExceptionHandler(value = BusinessException.class) 代码中的 value值就是 处理业务异常类。

1.2 处理业务异常类

public class BusinessException extends RuntimeException {private static final long serialVersionUID = 1L;/*** 错误码*/protected String errorCode;/*** 错误信息*/protected String errorMsg;public BusinessException() {super();}public BusinessException(String errorMsg) {super(errorMsg);this.errorMsg = errorMsg;this.errorCode = ResultEnum.FAILED.getCode();}public BusinessException(String errorCode, String errorMsg) {super(errorCode);this.errorCode = errorCode;this.errorMsg = errorMsg;}public BusinessException(String errorCode, String errorMsg, Throwable cause) {super(errorCode, cause);this.errorCode = errorCode;this.errorMsg = errorMsg;}public String getErrorCode() {return errorCode;}public void setErrorCode(String errorCode) {this.errorCode = errorCode;}public String getErrorMsg() {return errorMsg;}public void setErrorMsg(String errorMsg) {this.errorMsg = errorMsg;}public String getMessage() {return errorMsg;}@Overridepublic Throwable fillInStackTrace() {return this;}}

1.3 状态码枚举类

public enum ResultEnum {SUCCESS("0","执行成功"),FAILED("-1","执行失败"),BIZ_EXCEPTION("500","系统异常"),IDENTITY_IS_OVERDUE("1","身份过期"),//可以继续扩展定义;private String code;private String value;ResultEnum(String code, String value) {this.code = code;this.value = value;}public String getCode() {return code;}public void setCode(String code) {this.code = code;}public String getValue() {return value;}public void setValue(String value) {this.value = value;}
}

注意：需要继承RuntimeException异常，因为我们处理的业务异常全部都是运行时异常。

1.3 使用

在需要抛出业务异常的地方：

//自定义提示信息
throw new BusinessException("发生了业务异常!");
//自定义状态码
throw new BusinessException("502","发生了业务异常!");

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper,User> implements UserService {@Overridepublic List<UserVO> queryUserInfo() {int a = 1;if(a == 1){throw new BusinessException("502","发生了业务异常!");}return baseMapper.queryUserInfo();}
}

结果：

二、返回体配置

在上篇文章中我们在controller层返回的值直接是个集合：

这样是不符合规范的，我们需要定义一个含有code状态码、msg提示信息、data数据这三者的返回体。

2.1 返回体类

@Getter
@Setter
public class Response {/*** 响应码*/private String code;/*** 响应消息*/private String msg;/*** 响应结果*/private Object result;/*** 成功** @return*/public static Response success() {return new Response(ResultEnum.SUCCESS.getCode(),ResultEnum.SUCCESS.getValue(),null);}/*** 成功** @return*/public static Response success(String msg) {return new Response(ResultEnum.SUCCESS.getCode(),msg,null);}public Response() {}public Response(String code, String msg, Object result) {this.code = code;this.msg = msg;this.result = result;}/*** 成功* @param data* @return*/public static Response success(Object data) {Response rb = new Response();rb.setCode(ResultEnum.SUCCESS.getCode());rb.setMsg(ResultEnum.SUCCESS.getValue());rb.setResult(data);return rb;}/*** 失败*/public static Response error(String code, String message) {Response rb = new Response();rb.setCode(code);rb.setMsg(message);rb.setResult(null);return rb;}/*** 失败*/public static Response error(String message) {Response rb = new Response();rb.setCode(ResultEnum.FAILED.getCode());rb.setMsg(message);rb.setResult(null);return rb;}@Overridepublic String toString() {return JSONObject.toJSONString(this);}
}

2.2 抽象controller

public abstract class AbstractController {public Response returnSuccess(){return Response.success();}public Response returnSuccess(Object data){return Response.success(data);}public Response returnSuccess(String msg){return Response.success(msg);}
}

我们需要每个controller都继承AbstractController

2.3 使用

@RestController
@RequestMapping("/user")
public class UserController extends AbstractController {@Autowiredprivate UserService userService;@GetMapping("/users")public Response users(){return returnSuccess(userService.queryUserInfo());}
}

测试：

三、基础类

3.1 分页基础类

@Getter
@Setter
public class BasePageDTO{/*** 页数*/@Min(1)private Integer pageNum;/*** 页数*/private Integer pageSize;/*** 排序规则*/private String sortOrder;/*** 排序字段*/private String sortProp;}

这个分页的基础类在你需要分页的入参QO或者DTO中继承：

public class UserPageQO extends BasePageDTO {}

3.2 实体类基础类（可以不使用）

实体类基础类中包含数据库表中都有的字段，比如 是否删除标识、创建时间、创建人、修改时间、修改人等，根据自己实际情况做出调整。

@Getter
@Setter
public class BaseEntity {@TableId(type = IdType.UUID)private String id;@TableField("delete_flag")private Boolean deleteFlag;@TableField("create_time")private Date createTime;@TableField("modify_time")private Date modifyTime;@TableField("create_user")private String createUser;@TableField("modify_user")private String modifyUser;
}

全部的实体类都要继承BaseEntity：

@TableName("user")
public class User extends BaseEntity {private String name;private Integer age;public User() {}public User(Long id, String name, Integer age) {this.name = name;this.age = age;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}
}

实体类中就可以省略掉BaseEntity 已经存在的属性，比如id。