DTO 中返回 Enum 類的通用寫法

1.寫一個通用接口

public interface CodeEnum<T> {
    T getCode();
}

2.枚舉類中實現接口

@Getter
public enum OrderStatusEnum implements CodeEnum<Integer> {
    NEW(0, "新訂單"),
    FINISHED(1, "完結"),
    CANCEL(2, "已取消"),;

    private Integer code;
    private String msg;

    OrderStatusEnum(Integer code, String msg) {
        this.code = code;
        this.msg = msg;
    }
}

3.建一個工具 類

public class EnumUtil {
    public static <T extends CodeEnum> T getByCode(Integer code, Class<T> enumClass) {
        for (T each : enumClass.getEnumConstants()) {
            if (code.equals(each.getCode())) {
                return each;
            }
        }
        return null;
    }
}

4.dto 類中引用

@Data
//@JsonInclude(JsonInclude.Include.NON_NULL)
public class OrderDTO {

    private String orderId;
    private String buyerName;
    private String buyerPhone = "";
    private String buyerAddress;
    private String buyerOpenid;

    //訂單總金額
    private BigDecimal orderAmount;

    //訂單狀態 默認0新訂單
    private Integer orderStatus;

    //支付狀態 默認0未支付
    private Integer payStatus;

    //    @JsonSerialize
//    @DateTimeFormat(pattern = "yyyy-MM-dd")
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private Date createTime;
    private Date updateTime;

    List<OrderDetail> orderDetailList;

    @JsonIgnore  //對象轉json 格式可以忽略
    public OrderStatusEnum getOrderStatusEnum() {
        return EnumUtil.getByCode(orderStatus, OrderStatusEnum.class);
    }

}