package helpers;
import java.util.Collection;
public class LevensteinDistance {
private static int minimum(int a, int b, int c) {
return Math.min(Math.min(a, b), c);
}
public static int computeLevenshteinDistance(CharSequence str1,
CharSequence str2) {
int[][] distance = new int[str1.length() + 1][str2.length() + 1];
for (int i = 0; i <= str1.length(); i++)
distance[i][0] = i;
for (int j = 0; j <= str2.length(); j++)
distance[0][j] = j;
for (int i = 1; i <= str1.length(); i++)
for (int j = 1; j <= str2.length(); j++)
distance[i][j] = minimum(
distance[i - 1][j] + 1,
distance[i][j - 1] + 1,
distance[i - 1][j - 1]
+ ((str1.charAt(i - 1) == str2.charAt(j - 1)) ? 0
: 1));
return distance[str1.length()][str2.length()];
}
public static <K extends CharSequence> K getClosest(Collection<K> strings,CharSequence closestTo) {
int minDistance= Integer.MAX_VALUE;
K closest = null;
for (K s:strings) {
int currentDistance = computeLevenshteinDistance(s, closestTo);
System.out.println(s+" distance: "+currentDistance);
if (currentDistance < minDistance) {
closest = s;
minDistance = currentDistance;
}
}
return closest;
}
}