SpringBoot中@RestControllerAdvice注解实现全局异常处理类

@Slf4j
@RestControllerAdvice
public class GlobalExceptionHandler {
    private static final String DEFAULT_ERROR_MESSAGE = "系统繁忙，请稍后再试";
    @ExceptionHandler(value = {SQLIntegrityConstraintViolationException.class})
    public DataVO handleSQLIntegrityConstraintViolationException(SQLIntegrityConstraintViolationException e) {
        log.error(e.getMessage(), e);
        return new DataVO(SysConstant.CODE_ERROR, "当前主键存在于其他表的外键约束，请先处理父表中的该外键");
    }
    @ExceptionHandler(value = {FileNotFoundException.class})
    public DataVO handleFileNotFoundException(FileNotFoundException e) {
        log.error(e.getMessage(), e);
        return new DataVO(SysConstant.CODE_ERROR, "路径不存在");
    }
    @ExceptionHandler(value = {Exception.class})
    public DataVO handleException(Exception e) {
        log.error(e.getMessage(), e);
        return new DataVO(SysConstant.CODE_ERROR, DEFAULT_ERROR_MESSAGE);
    }
}

@Slf4j
@RestControllerAdvice
public class GlobalExceptionHandler {
    private static final String DEFAULT_ERROR_MESSAGE = "系统繁忙，请稍后再试";
    @ExceptionHandler(value = {SQLIntegrityConstraintViolationException.class})
    public DataVO handleSQLIntegrityConstraintViolationException(SQLIntegrityConstraintViolationException e) {
        log.error(e.getMessage(), e);
        return handleException(DEFAULT_ERROR_MESSAGE, e);
    }
    @ExceptionHandler(value = {FileNotFoundException.class})
    public DataVO handleFileNotFoundException(FileNotFoundException e) {
        log.error(e.getMessage(), e);
        return handleException(DEFAULT_ERROR_MESSAGE, e);
    }
    @ExceptionHandler(value = {Exception.class})
    public DataVO handleException(Exception e) {
        log.error(e.getMessage(), e);
        return handleException(DEFAULT_ERROR_MESSAGE, e);
    }
    private DataVO handleException(String defaultMessage, Throwable e) {
        if (e instanceof BusinessException) {
            return new DataVO(SysConstant.CODE_ERROR, e.getMessage());
        } else if (e instanceof MethodArgumentNotValidException) {
            return new DataVO(SysConstant.CODE_ERROR, ((MethodArgumentNotValidException) e).getBindingResult().getFieldError().getDefaultMessage());
        } else {
            return new DataVO(SysConstant.CODE_ERROR, defaultMessage);
        }
    }
}

@Slf4j
@RestControllerAdvice
public class GlobalExceptionHandler {
    private static final String errorMsg = SysConstant.DEFAULT_ERROR;
    private static final Map<Class<? extends Throwable>, Function<Throwable, DataVO<Null>>> EXCEPTION_HANDLER_MAP = new HashMap<>();
    static {
        EXCEPTION_HANDLER_MAP.put(RuntimeException.class, e -> new DataVO<>(SysConstant.CODE_ERROR, e.getMessage()));
        EXCEPTION_HANDLER_MAP.put(DataIntegrityViolationException.class, e -> new DataVO<>(SysConstant.CODE_ERROR, "当前主键存在于其他表的外键约束，请先处理父表中的该外键"));
        EXCEPTION_HANDLER_MAP.put(FileNotFoundException.class, e -> new DataVO<>(SysConstant.CODE_ERROR, "路径不存在"));
    }
    @ExceptionHandler(Exception.class)
    public DataVO<Null> handleException(Exception e) {
        log.error(e.toString());
        return EXCEPTION_HANDLER_MAP.getOrDefault(e.getClass(), t -> new DataVO<>(SysConstant.CODE_ERROR, errorMsg)).apply(e);
    }
}

@Data
//@JsonPropertyOrder({"code","msg","count","data"})//指定返回给前端的字段顺序
public class DataVO<T> {
    private Integer code = 0;
    private String msg = "";
    private Long count;
    private List<T> data;
    public DataVO() {
    }
    public DataVO(Integer code, String msg) {
        this.code = code;
        this.msg = msg;
    }
    public DataVO(Integer code, String msg, Long count, List<T> data) {
        this.code = code;
        this.msg = msg;
        this.count = count;
        this.data = data;
    }
}