使用逗号按位数对数字进行分割输出

/**
 * 使用逗号按位数对数字进行分割输出
 * @param num
 * @param seperateBit
 * @return
 */
public static String spilitNUm(long num, int seperateBit){
    if (seperateBit<0){
        return null;
    }
    String s = String.valueOf(num);
    ArrayList<Character> characters = new ArrayList<>();
    for (int i = 0; i < s.length(); i++) {
        characters.add(s.charAt(i));
    }
    int count=0;
    StringBuilder stringBuilder = new StringBuilder();
    int countIndex=0;
    for (Character character : characters) {
        int i = count + 1;
        if (i<seperateBit){
            if (!(i%seperateBit==0)){
                stringBuilder.append(character);
                count++;
                countIndex++;
                if (s.length()==(countIndex+1)){
                    break;
                }
                continue;
            }else {
                stringBuilder.append(",");
                count-=seperateBit;
                continue;
            }
        }else {
            i-=1;
            if (!(i%seperateBit==0)){
                stringBuilder.append(character);
                count++;
                countIndex++;
                if (s.length()==(countIndex+1)){
                    break;
                }
                continue;
            }else {
                stringBuilder.append(",");
                count-=seperateBit;
                continue;
            }
        }
    }
    String string = stringBuilder.toString();
    return string;
}