com.naver.divideandconquer.levenshtein.Levenshtein.java Source code

Introduction

Here is the source code for com.naver.divideandconquer.levenshtein.Levenshtein.java

Source

/*
 *@(#)Levenshtein.java 2018.02.07
 *
 * Copyright 2018 NHN Corp. All rights Reserved.
 * NHN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package com.naver.divideandconquer.levenshtein;

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.math.NumberUtils;

/**
 *
 *
 * @author kim.minjoo
 */
public class Levenshtein {
    public static int calculateDistance(String str1, String str2) {
        return calculateDistance(str1, str2, 0);
    }

    private static int calculateDistance(String str1, String str2, int distance) {
        if (StringUtils.isBlank(str1) && StringUtils.isBlank(str2)) {
            return distance;
        }

        if (StringUtils.isBlank(str1)) {
            return distance + str2.length();
        }

        if (StringUtils.isBlank(str2)) {
            return distance + str1.length();
        }

        boolean isEqualEndChar = str1.charAt(str1.length() - 1) == str2.charAt(str2.length() - 1);

        if (isEqualEndChar) {
            return calculateDistance(str1.substring(0, str1.length() - 1), str2.substring(0, str2.length() - 1),
                    distance);
        } else {
            int case1 = calculateDistance(str1.substring(0, str1.length() - 1),
                    str2.substring(0, str2.length() - 1), distance + 1);
            int case2 = calculateDistance(str1, str2.substring(0, str2.length() - 1), distance + 1);
            int case3 = calculateDistance(str1.substring(0, str1.length() - 1), str2, distance + 1);

            return NumberUtils.min(case1, case2, case3);
        }
    }
}