Android String与十六进制数互转

    /**
     * 字符串转换成十六进制字符串
     * @param String str 待转换的ASCII字符串
     * @return String 每个Byte之间空格分隔，如: [61 6C 6B]
     */
    public static String str2HexStr(String str)
    {    

        char[] chars = "0123456789ABCDEF".toCharArray();
        StringBuilder sb = new StringBuilder("");
        byte[] bs = str.getBytes();
        int bit;    

        for (int i = ; i < bs.length; i++)
        {
            bit = (bs[i] & 0x0f0) >> ;
            sb.append(chars[bit]);
            bit = bs[i] & 0x0f;
            sb.append(chars[bit]);
            sb.append(' ');
        }
        return sb.toString().trim();
    }  

    /**
     * 十六进制转换字符串
     * @param String str Byte字符串(Byte之间无分隔符 如:[616C6B])
     * @return String 对应的字符串
     */
    public static String hexStr2Str(String hexStr)
    {
        String str = "0123456789ABCDEF";
        char[] hexs = hexStr.toCharArray();
        byte[] bytes = new byte[hexStr.length() / ];
        int n;    

        for (int i = ; i < bytes.length; i++)
        {
            n = str.indexOf(hexs[ * i]) * ;
            n += str.indexOf(hexs[ * i + ]);
            bytes[i] = (byte) (n & 0xff);
        }
        return new String(bytes);
    }  

    /**
     * bytes转换成十六进制字符串
     * @param byte[] b byte数组
     * @return String 每个Byte值之间空格分隔
     */
    public static String byte2HexStr(byte[] b)
    {
        String stmp="";
        StringBuilder sb = new StringBuilder("");
        for (int n=;n<b.length;n++)
        {
            stmp = Integer.toHexString(b[n] & 0xFF);
            sb.append((stmp.length()==)? ""+stmp : stmp);
            sb.append(" ");
        }
        return sb.toString().toUpperCase().trim();
    }  

    /**
     * bytes字符串转换为Byte值
     * @param String src Byte字符串，每个Byte之间没有分隔符
     * @return byte[]
     */
    public static byte[] hexStr2Bytes(String src)
    {
        int m=,n=;
        int l=src.length()/;
        System.out.println(l);
        byte[] ret = new byte[l];
        for (int i = ; i < l; i++)
        {
            m=i*+;
            n=m+;
            ret[i] = Byte.decode("0x" + src.substring(i*, m) + src.substring(m,n));
        }
        return ret;
    }  

    /**
     * String的字符串转换成unicode的String
     * @param String strText 全角字符串
     * @return String 每个unicode之间无分隔符
     * @throws Exception
     */
    public static String strToUnicode(String strText)
        throws Exception
    {
        char c;
        StringBuilder str = new StringBuilder();
        int intAsc;
        String strHex;
        for (int i = ; i < strText.length(); i++)
        {
            c = strText.charAt(i);
            intAsc = (int) c;
            strHex = Integer.toHexString(intAsc);
            if (intAsc > )
                str.append("\\u" + strHex);
            else // 低位在前面补00
                str.append("\\u00" + strHex);
        }
        return str.toString();
    }  

    /**
     * unicode的String转换成String的字符串
     * @param String hex 16进制值字符串 （一个unicode为2byte）
     * @return String 全角字符串
     */
    public static String unicodeToString(String hex)
    {
        int t = hex.length() / ;
        StringBuilder str = new StringBuilder();
        for (int i = ; i < t; i++)
        {
            String s = hex.substring(i * , (i + ) * );
            // 高位需要补上00再转
            String s1 = s.substring(, ) + "";
            // 低位直接转
            String s2 = s.substring();
            // 将16进制的string转为int
            int n = Integer.valueOf(s1, ) + Integer.valueOf(s2, );
            // 将int转换为字符
            char[] chars = Character.toChars(n);
            str.append(new String(chars));
        }
        return str.toString();
    }