根据序列产生不重复的难以找到规律的数字

NumberMixer.java

package com.best.buc.base.manager.serialnum.generator.seq;

import org.apache.commons.lang.ArrayUtils;

import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

/**
 * @author Fu Yun
 */
class NumberMixer {
    private final int[] mixArr;

    public NumberMixer() {
        List<Integer> list = IntStream.range(0, 10).boxed().collect(Collectors.toList());
        Collections.shuffle(list);
        mixArr = list.stream().mapToInt(Integer::intValue).toArray();
    }

    public NumberMixer(String mixArrStr) {
        mixArr = new int[10];
        for (int i = 0; i < mixArrStr.length(); i++) {
            mixArr[i] = mixArrStr.charAt(i) - '0';
        }
    }

    /**
     * 获取混淆数组
     * @return 混淆数组
     */
    public String getMixArr() {
        StringBuilder sb = new StringBuilder();
        for (int i : mixArr) {
            sb.append((char) (i + '0'));
        }
        return sb.toString();
    }

    /**
     * 混淆原始的数字，使产生的数字很难看出规律
     * @param original 数字字符串 eg: "32663"
     * @return 混淆后的字符串
     */
    public String mix(String original) {
        char[] chars = original.toCharArray();
        ArrayUtils.reverse(chars);
        int pre = 0;
        for (int i = 0; i < chars.length; i++) {
            int num = chars[i] - '0';
            int res = (num + pre) % 10;
            res = mixArr[res];
            pre = res;
            chars[i] = (char) (res + '0');
        }
        return String.valueOf(chars);
    }
}