Java 枚举策略模式：用枚举替换 if-else 分发的三种绑定方式

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public enum TimeUnitEnum {
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    SECOND("SEC", "秒") {
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        @Override
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        public Date addTime(Date date, Integer interval) {
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            return DateUtil.offsetSecond(date, interval);
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        }
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        @Override
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        public Date subTime(Date date, Integer interval) {
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            return DateUtil.offsetSecond(date, -interval);
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        }
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    },
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    MINUTE("MIN", "分钟") {
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        @Override
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        public Date addTime(Date date, Integer interval) {
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            return DateUtil.offsetMinute(date, interval);
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        }
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        @Override
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        public Date subTime(Date date, Integer interval) {
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            return DateUtil.offsetMinute(date, -interval);
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        }
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    },
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    HOUR("HR", "小时") {
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        @Override
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        public Date addTime(Date date, Integer interval) {
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            return DateUtil.offsetHour(date, interval);
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        }
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        @Override
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        public Date subTime(Date date, Integer interval) {
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            return DateUtil.offsetHour(date, -interval);
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        }
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    },
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    DAY("DAY", "天") {
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        @Override
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        public Date addTime(Date date, Integer interval) {
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            return DateUtil.offsetDay(date, interval);
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        }
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        @Override
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        public Date subTime(Date date, Integer interval) {
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            return DateUtil.offsetDay(date, -interval);
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        }
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    };
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    /** 实体字段声明为枚举类型时，MyBatis-Plus 按此字段的值读写数据库列。 */
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    @EnumValue
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    private final String code;
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    private final String info;
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    TimeUnitEnum(String code, String info) {
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        this.code = code;
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        this.info = info;
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    }
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    public String getCode() {
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        return code;
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    }
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    public String getInfo() {
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        return info;
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    }
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    /** 加 / 减 interval 个当前单位。 */
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    public abstract Date addTime(Date date, Integer interval);
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    public abstract Date subTime(Date date, Integer interval);
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    private static final Map<String, TimeUnitEnum> CODE_MAP = Arrays.stream(values())
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            .collect(Collectors.toMap(TimeUnitEnum::getCode, Function.identity()));
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    /** fail fast：脏配置拦在入口。 */
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    @JsonCreator
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    public static TimeUnitEnum getEnumByCode(String code) {
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        TimeUnitEnum unit = CODE_MAP.get(code);
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        if (unit == null) {
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            throw new IllegalArgumentException("未知时间单位 code: " + code);
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        }
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        return unit;
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    }
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    /** 允许降级的场景单独走可空查找，决策留在调用方。 */
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    public static TimeUnitEnum findOrNull(String code) {
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        return CODE_MAP.get(code);
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    }
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}

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@Getter
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public enum DataCollectEnum {
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    MATERIAL("MATERIAL", "同步物料") {
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        @Override
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        public void execute(DataCollectService service, CollectContext ctx) {
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            service.collectMaterial(ctx);
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        }
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    },
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    ORDER("ORDER", "同步订单") {
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        @Override
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        public void execute(DataCollectService service, CollectContext ctx) {
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            service.collectOrder(ctx);
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        }
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    },
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    ITEM("ITEM", "ITEM 数据收集") {
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        @Override
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        public void execute(DataCollectService service, CollectContext ctx) {
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            service.collectItems(ctx);
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        }
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    };
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    private final String code;
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    private final String name;
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    DataCollectEnum(String code, String name) {
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        this.code = code;
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        this.name = name;
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    }
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    /** 统一操作入口，service 由调用方传入。 */
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    public abstract void execute(DataCollectService service, CollectContext ctx);
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    private static final Map<String, DataCollectEnum> CODE_MAP = Arrays.stream(values())
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            .collect(Collectors.toMap(DataCollectEnum::getCode, Function.identity()));
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    /** Optional 版查找：未知 code 返回 empty，跳过还是报错由调用方决定。 */
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    public static Optional<DataCollectEnum> getByCode(String code) {
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        return Optional.ofNullable(CODE_MAP.get(code));
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    }
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    public static String getNameByCode(String code) {
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        return getByCode(code).map(DataCollectEnum::getName).orElse("");
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    }
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}