一.自定義自己的異常類MyException.java

public class MyException extends RuntimeException {
    private int code;

    public MyException( int code, String message ) {
        super(message);
        this.code = code;
    }

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }
}
 

二.統一異常返回格式Result.java

public class Result implements Serializable {
    private int code;
    private String msg;
    private Object data;

    public int getCode() {
        return code;
    }

    public void setCode(int 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;
    }
}
 

三.編寫全域性異常處理器MyExceptionHandle.java

@ControllerAdvice
public class MyExceptionHandle {
    private static final Logger logger = LoggerFactory.getLogger(MyExceptionHandle.class);

    @ExceptionHandler(value = Exception.class)
    @ResponseBody
    public Result handle(Exception e) {
        if(e instanceof MyException) {
            MyException myException = (MyException)e;
            return ResultUtil.error(myException.getCode(),myException.getMessage());
        }else{
            logger.error("系統異常",e);
            return ResultUtil.error(ResultEnum.UNKNOWN_ERROR.getCode(),ResultEnum.UNKNOWN_ERROR.getMsg());
        }
    }

}
 

四.其它類

ResultEnum.java：作用：規範錯誤碼code極其具體表示含義。方便維護。

public enum ResultEnum {

    UNKNOWN_ERROR(500,"未知錯誤"),
    SUCCESS(200,"操作成功"),
    ERROR_1(111,"未成年1"),
    ERROR_2(112,"未成年2");

    private int code;
    private String msg;

    ResultEnum(int code, String msg) {
        this.code = code;
        this.msg = msg;
    }

    public int getCode() {
        return code;
    }

    public String getMsg() {
        return msg;
    }
}

ResultUtil.java：作用：方便生成Result.java而已

public class ResultUtil {

    public static Result error(int code,String msg) {
        Result result = new Result();
        result.setCode(code);
        result.setMsg(msg);
        result.setData(null);
        return result;
    }

    public static Result success(Object obj) {
        Result result = new Result();
        result.setCode(200);
        result.setMsg("成功");
        result.setData(obj);
        return result;
    }

    public static Result success() {
        Result result = new Result();
        result.setCode(200);
        result.setMsg("成功");
        result.setData(null);
        return result;
    }

}

HelloController.java

@RestController
public class HelloController {

    @GetMapping("/aa")
    public Result aa(Girl girl) throws Exception {
        if(girl.getId() < 18) {
            throw new MyException(ResultEnum.ERROR_1.getCode(),ResultEnum.ERROR_1.getMsg());
        }else if(girl.getId() < 20) {
            throw new MyException(ResultEnum.ERROR_2.getCode(),ResultEnum.ERROR_2.getMsg());
        }
        return ResultUtil.success("aaa");
    }

}

五.測試結果

六.注意事項

[email protected]：等價於@Controller 、@ResponseBody一起使用

[email protected]：主要和@ExceptionHandler配合使用，來配置全域性異常處理器，另外@ControllerAdvice內部使用了@Component註解，因此會自動被spring容器載入。如圖：

七.總結

全域性異常處理器配置核心就是上面的註解。主要作用是為了將程式中可能出現的異常情況自己丟擲然後用通用的格式顯示。以便正確的處理錯誤。另外，程式碼如果想要優化就立馬優化，如果說以後優化基本就等於永遠不不會優化了。