求求你不要寫滿屏的 try...catch 了，這才是優雅的處理方式，真香！-有解無憂

作者：小李子說程式
來源：https://www.toutiao.com/i6878184496945070604

前言

軟體開發springboot專案程序中，不可避免的需要處理各種例外,spring mvc 架構中各層會出現大量的try {...} catch {...} finally {...}代碼塊，不僅有大量的冗余代碼，而且還影響代碼的可讀性，

Spring Boot 基礎就不介紹了，推薦下這個實戰教程：
https://github.com/javastacks/spring-boot-best-practice

這樣就需要定義個全域統一例外處理器，以便業務層再也不必處理例外，

實踐

1 封裝統一回傳結果類

源代碼

public class AjaxResult {
 //是否成功
    private Boolean success;
    //狀態碼
    private Integer code;
    //提示資訊
    private String msg;
    //資料
    private Object data;
    public AjaxResult() {

    }
    //自定義回傳結果的構造方法
    public AjaxResult(Boolean success,Integer code, String msg,Object data) {
        this.success = success;
        this.code = code;
        this.msg = msg;
        this.data = https://www.cnblogs.com/javastack/archive/2022/04/06/data;
    }
    //自定義例外回傳的結果
    public static AjaxResult defineError(BusinessException de){
     AjaxResult result = new AjaxResult();
        result.setSuccess(false);
        result.setCode(de.getErrorCode());
        result.setMsg(de.getErrorMsg());
        result.setData(null);
        return result;
    }
    //其他例外處理方法回傳的結果
    public static AjaxResult otherError(ErrorEnum errorEnum){
     AjaxResult result = new AjaxResult();
        result.setMsg(errorEnum.getErrorMsg());
        result.setCode(errorEnum.getErrorCode());
        result.setSuccess(false);
        result.setData(null);
        return result;
    }
 public Boolean getSuccess() {
  return success;
 }
 public void setSuccess(Boolean success) {
  this.success = success;
 }
 public Integer getCode() {
  return code;
 }
 public void setCode(Integer code) {
  this.code = code;
 }
 public String getMsg() {
  return msg;
 }
 public void setMsg(String msg) {
  this.msg = msg;
 }
 public Object getData() {
  return data;
 }
 public void setData(Object data) {
  this.data = data;
 }

}

2 自定義例外封裝類

原始碼：

public class BusinessException extends RuntimeException {
 private static final long serialVersionUID = 1L;
 /**
  * 錯誤狀態碼
  */
 protected Integer errorCode;
 /**
  * 錯誤提示
  */
 protected String errorMsg;

 public BusinessException(){

     }

 public BusinessException(Integer errorCode, String errorMsg) {
         this.errorCode = errorCode;
         this.errorMsg = errorMsg;
     }

 public Integer getErrorCode() {
  return errorCode;
 }

 public void setErrorCode(Integer errorCode) {
  this.errorCode = errorCode;
 }

 public String getErrorMsg() {
  return errorMsg;
 }

 public void setErrorMsg(String errorMsg) {
  this.errorMsg = errorMsg;
 }
}

3 錯誤列舉，拒絕硬編碼

原始碼

public enum ErrorEnum {
 // 資料操作錯誤定義
 SUCCESS(200, "成功"),
 NO_PERMISSION(403,"你沒得權限"),
 NO_AUTH(401,"未登錄"),
 NOT_FOUND(404, "未找到該資源!"),
 INTERNAL_SERVER_ERROR(500, "服務器例外請聯系管理員"),
 ;

 /** 錯誤碼 */
 private Integer errorCode;

 /** 錯誤資訊 */
 private String errorMsg;

 ErrorEnum(Integer errorCode, String errorMsg) {
  this.errorCode = errorCode;
  this.errorMsg = errorMsg;
 }

    public Integer getErrorCode() {
        return errorCode;
    }

    public String getErrorMsg() {
        return errorMsg;
    }
}

4 全域例外處理類

原始碼

/**
 * 全域例外處理器
 *
 */
@RestControllerAdvice
public class GlobalExceptionHandler
{
    private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    /**
     * 處理自定義例外
     *
     */
    @ExceptionHandler(value = https://www.cnblogs.com/javastack/archive/2022/04/06/BusinessException.class)
    public AjaxResult bizExceptionHandler(BusinessException e) {
     log.error(e.getMessage(), e);
        return AjaxResult.defineError(e);
    }

    /**
     *處理其他例外
     *
     */
    @ExceptionHandler(value = Exception.class)
    public AjaxResult exceptionHandler( Exception e) {
      log.error(e.getMessage(), e);
        return AjaxResult.otherError(ErrorEnum.INTERNAL_SERVER_ERROR);

    }

}