hasher.java

// direct translation for https://gist.github.com/sauron/9773864
public class Example {
	public static void main(String[] args) {
		System.out.println(hash("leepadg"));
		System.out.println(unhash(680131659347L));

	}

	static String letters = "acdegilmnoprstuw";

	static long hash(String s) {
		long h = 7;
		for (int i = 0; i < s.length(); i++) {
			int var = letters.indexOf(s.charAt(i));
			h = (h * 37 + var);
		}
		return h;
	}

	static String unhash(long h) {
		StringBuffer sb = new StringBuffer();
		while (h > 7) {
			Object[] obj = getNumberAndChar(h);
			h = (long) obj[0];
			sb.append((char) obj[1]);
		}
		return sb.reverse().toString();
	}

	static Object[] getNumberAndChar(long h) {
		for (int i = 0; i < letters.length(); i++) {
			if ((h - i) % 37 == 0) {
				return new Object[] { h / 37, letters.charAt(i) };
			}
		}
		return new Object[] { 0, '\0' };
	}

}

Nice! 😉