Java实现 整型转字符串，位数不足时可以自动补0

public class StringUtil {
    /**
     * 整型转字符串并格式化
     * @param minSize 最小大小
     * @param separator 分隔符
     * @param intNums 需要转化的整数
     * @return 字符串
     */
    public static String formatInt(int minSize, String separator, int...intNums) {
        StringBuilder stringBuilder = new StringBuilder("");
        for (int i = 0; i < intNums.length; i++) {
            if(i != 0) {
                stringBuilder.append(separator);
            }
            String s = String.valueOf(intNums[i]);
            int zeroNum = minSize - s.length();
            if(zeroNum > 0) {
                appendZeroInHead(stringBuilder, zeroNum);
            }

            stringBuilder.append(s);
        }

        return stringBuilder.toString();
    }

    private static void appendZeroInHead(StringBuilder sb, int zeroNum) {
        for (int i = 0; i < zeroNum; i++) {
            sb.append("0");
        }
    }

}

    public static void main(String[] args) {
        String s = formatInt(2, "-", 1, 2, 3, 4, 10, 20, 900);
        System.out.println(s);
    }

    public static void main(String[] args) {
        String s = formatInt(3, ",", 1, 2, 3, 4, 10, 20, 900);
        System.out.println(s);
    }