java ASCII转换为16进制

/**
     * ASCII转换为16进制
     *
     * @param bytes  源数据
     * @param offset 偏移量
     * @param length 数据长度
     * @return {@link String}
     */
    public String convertHexToAscii(byte[] bytes, int offset, int length) {
        StringBuilder sb = new StringBuilder();
        int step = 2;
        for (int k = 0; k < length; k++) {
            String hex = HexUtil.toHex(bytes[offset + k]);
            for (int i = 0; i < hex.length() - 1; i += step) {
                String output = hex.substring(i, (i + step));
                int decimal = Integer.parseInt(output, 16);
                sb.append((char) decimal);
            }
        }
        return sb.toString();

    }