JAVA的TLV组解包

有项目使用到了TLV组解包的模式，特意在此记录，以供参考：

/**
 * 将字符串转换为TLV对象
 * Created by ZFR on 2019/5/29.
 */
public class TlvUtils {
    /**
     * 将16进制字符串转换为TLV对象列表
     *
     * @param hexString
     * @return
     */
    public static List builderTlvList(String hexString) {
        List tlvs = new ArrayList();

        int position = 0;
        while (position != StringUtils.length(hexString)) {
            String _hexTag = getTag(hexString, position);
            Log.d("zfr-_hexTag:===", _hexTag);
            position += _hexTag.length();

            LPositon l_position = getLengthAndPosition(hexString, position);
            int _vl = l_position.get_vL();

            position = l_position.get_position();

            String _value = StringUtils.substring(hexString, position, position + _vl * 2);

            position = position + _value.length();

            tlvs.add(new TLV2(_hexTag, _vl, _value));
        }
        return tlvs;
    }

    /**
     * 将16进制字符串转换为TLV对象MAP
     *
     * @param hexString
     * @return
     */
    public static Map builderTlvMap(String hexString) {

        Map tlvs = new HashMap();

        int position = 0;
        while (position != hexString.length()) {
            String _hexTag = getTag(hexString, position);

            position += _hexTag.length();

            LPositon l_position = getLengthAndPosition(hexString, position);

            int _vl = l_position.get_vL();
            position = l_position.get_position();
            String _value = hexString.substring(position, position + _vl * 2);
            position = position + _value.length();

            tlvs.put(_hexTag, new TLV2(_hexTag, _vl, _value));
        }
        return tlvs;
    }

    /**
     * 返回最后的Value的长度
     *
     * @param hexString
     * @param position
     * @return
     */
    private static LPositon getLengthAndPosition(String hexString, int position) {
        String firstByteString = hexString.substring(position, position + 4);
        Log.d("zfr-firstByteString====", firstByteString);
        return new LPositon(Integer.parseInt(zfrUtils.toStringHex(firstByteString)), position + 4);
        /*int i = Integer.parseInt(firstByteString, 16);
        String hexLength = "";

        if (((i >>> 7) & 1) == 0) {
            hexLength = hexString.substring(position, position + 2);
            position = position + 2;
        } else {
            // 当最左侧的bit位为1的时候，取得后7bit的值，
            int _L_Len = i & 127;
            position = position + 2;
            hexLength = hexString.substring(position, position + _L_Len * 2);
            // position表示第一个字节，后面的表示有多少个字节来表示后面的Value值
            position = position + _L_Len * 2;
        }
        return new LPositon(Integer.parseInt(hexLength, 16), position);*/

    }

    /**
     * 取得子域Tag标签
     *
     * @param hexString
     * @param position
     * @return
     */
    private static String getTag(String hexString, int position) {
        String firstByte = StringUtils.substring(hexString, position, position + 4);
        Log.d("zfr-firstByte:==", firstByte);
        return hexString.substring(position, position + 4);
        /*int i = Integer.parseInt(firstByte, 16);
        Log.d("zfr-i:==",i+"");
        if ((i & 0x1f) == 0x1f) {
            Log.d("zfr-2字节：=====","0000000000");
            return hexString.substring(position, position + 4);
        } else {
            Log.d("zfr-1字节：=====","0000000000");
            return hexString.substring(position, position + 2);
        }*/
    }
}

 

注：如有问题可以回复，看到第一时间分析解决，码农不易，感觉对您有用，帮助到您，可否打赏一杯可乐，在此谢过诸位，愿诸君终成大神，前程似锦~~~