public int computeLevenshteinDistance(String source, String target) {
		source = source.toLowerCase();
		target = target.toLowerCase();

		int[] costs = new int[target.length() + 1];
		for (int i = 0; i <= source.length(); i++) {
			int lastValue = i;
			for (int j = 0; j <= target.length(); j++) {
				if (i == 0)
					costs[j] = j;
				else {
					if (j > 0) {
						int newValue = costs[j - 1];
						if (source.charAt(i - 1) != target.charAt(j - 1))
							newValue = Math.min(Math.min(newValue, lastValue),
									costs[j]) + 1;
						costs[j - 1] = lastValue;
						lastValue = newValue;
					}
				}
			}
			if (i > 0)
				costs[target.length()] = lastValue;
		}
		return costs[target.length()];
	}