基于Redis实现分布式单号及分布式ID(自定义规则生成)

public class FORMNoConstants {
    
    public static final String SERIAL_CACHE_PREFIX = "FORM_NO_CACHE_";

    
    public static final String SERIAL_YYMMDD_PREFIX = "yyMMdd";

    
    public static final String SERIAL_YYYYMMDD_PREFIX = "yyyyMMdd";
    
    
    public static final int DEFAULT_CACHE_DAYS = 7;
}

public enum FormNoTypeEnum {

    
    YF_ORDER("YF", FormNoConstants.SERIAL_YYYYMMDD_PREFIX, 7, 3, 20),

    
    FK_ORDER("FK", FormNoConstants.SERIAL_YYYYMMDD_PREFIX, 7, 3, 20),

    
    TEST_ORDER("te", FormNoConstants.SERIAL_YYYYMMDD_PREFIX, 10, 0, 20),
    ;

    
    private String prefix;

    
    private String datePattern;

    
    private Integer serialLength;
    
    private Integer randomLength;

    
    private Integer totalLength;


    FormNoTypeEnum(String prefix, String datePattern, Integer serialLength, Integer randomLength, Integer totalLength) {
        this.prefix = prefix;
        this.datePattern = datePattern;
        this.serialLength = serialLength;
        this.randomLength = randomLength;
        this.totalLength = totalLength;
    }
    //省略 get 方法
}

public class FormNoSerialUtil {

    
    public static String getFormNoPrefix(FormNoTypeEnum formNoTypeEnum) {
        //格式化时间
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern(formNoTypeEnum.getDatePattern());
        StringBuffer sb = new StringBuffer();
        sb.append(formNoTypeEnum.getPrefix());
        sb.append(formatter.format(LocalDateTime.now()));
        return sb.toString();
    }
    
    
    public static String getCacheKey(String serialPrefix) {
        return FormNoConstants.SERIAL_CACHE_PREFIX.concat(serialPrefix);
    }
    
    
    public static String completionSerial(String serialPrefix, Long incrementalSerial,
                                          FormNoTypeEnum formNoTypeEnum) {
        StringBuffer sb = new StringBuffer(serialPrefix);

        //需要补0的长度=流水号长度 -当日自增计数长度
        int length = formNoTypeEnum.getSerialLength() - String.valueOf(incrementalSerial).length();
        //补零
        for (int i = 0; i < length; i++) {
            sb.append("0");
        }
        //redis当日自增数
        sb.append(incrementalSerial);
        return sb.toString();
    }


    
    public static String completionRandom(String serialWithPrefix, FormNoTypeEnum formNoTypeEnum) {
        StringBuffer sb = new StringBuffer(serialWithPrefix);
        //随机数长度
        int length = formNoTypeEnum.getRandomLength();
        if (length > 0) {
            Random random = new Random();
            for (int i = 0; i < length; i++) {
                //十以内随机数补全
                sb.append(random.nextInt(10));
            }
        }
        return sb.toString();
    }
}

public interface FormNoGenerateService {

    
    String generateFormNo(FormNoTypeEnum formNoTypeEnum);
}

@Service
public class FormNoGenerateServiceImpl implements FormNoGenerateService {
    
    @Autowired
    private RedisCache redisCache;
    
    @Override
    public String generateFormNo(FormNoTypeEnum formNoTypeEnum) {
        //获得单号前缀
        //格式 固定前缀 +时间前缀 示例 ：YF20190101
        String formNoPrefix = FormNoSerialUtil.getFormNoPrefix(formNoTypeEnum);
        //获得缓存key
        String cacheKey = FormNoSerialUtil.getCacheKey(formNoPrefix);
        //获得当日自增数
        Long incrementalSerial = redisCache.incr(cacheKey);
        //设置失效时间 7天
        redisCache.expire(cacheKey, FormNoConstants.DEFAULT_CACHE_DAYS, TimeUnit.DAYS);
        //组合单号并补全流水号
        String serialWithPrefix = FormNoSerialUtil
                .completionSerial(formNoPrefix, incrementalSerial, formNoTypeEnum);
        //补全随机数
        return FormNoSerialUtil.completionRandom(serialWithPrefix, formNoTypeEnum);
    }
}