base37.java

	/**
	 * Encodes a string into its base37 integral value
	 * 
	 * @param str the string to encode
	 * @return the base37 value
	 */
	public static long encodeb37(String str) {
		String str1 = "";
		for (int i = 0; i < str.length(); i++) {
			char c = str.charAt(i);
			if (c >= 'a' && c <= 'z')
				str1 = str1 + c;
			else if (c >= 'A' && c <= 'Z')
				str1 = str1 + (char)((c + 97) - 65);
			else if (c >= '0' && c <= '9')
				str1 = str1 + c;
			else
				str1 = str1 + ' ';
		}

		str1 = str1.trim();
		if(str1.length() > 12)
			str1 = str1.substring(0, 12);
		long base = 0L;
		for (int i = 0; i < str1.length(); i++) {
			char c1 = str1.charAt(i);
			base *= 37L;
			if (c1 >= 'a' && c1 <= 'z')
				base += (1 + c1) - 97;
			else if(c1 >= '0' && c1 <= '9')
				base += (27 + c1) - 48;
		}
		return base;
	}

	/**
	 * Decodes a base37 integral value into a string
	 * 
	 * @param base the base37 value
	 * @return the decoded string value
	 */
	public static String decodeb37(long base) {
		if(base < 0L)
			return "invalid_name";
		String str = "";
		while(base != 0L) {
			int value = (int)(base % 37L);
			base /= 37L;
			if (value == 0)
				str = " " + str;
			else if (value < 27) {
				if (base % 37L == 0L)
					str = (char)((value + 65) - 1) + str;
				else
					str = (char)((value + 97) - 1) + str;
			} else {
				str = (char)((value + 48) - 27) + str;
			}
		}
		return str;
	}