如何计算java中两个字符串之间的匹配分数？

Question

我想将两个字符串分类为相似或不相似。例如

s1 = "Token is invalid. DeviceId = deviceId: "345" "
s2 = "Token is invalid. DeviceId = deviceId: "123" "
s3 = "Could not send Message."

我正在寻找一个可以在2个字符串之间给出匹配分数的java库，从中我可以确定它们是否相似。我的程序只需要处理一个小数据集（~2000字符串）。你知道那里有没有可用的东西吗？

Answer 1

检查Levenshtein距离以获得匹配分数

http://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Levenshtein_distance#Java

Answer 2

对于所有NLP java问题，您应该检查Apache Lucene项目。然而，根据您的需要，需要一个简单的Levenshtein距离算法

Answer 3

如建议的那样。 Levenshtein距离算法......

public class LevenshteinDistance
{
    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 = 1; 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 void main(String[] args)
    {
        String s1 = "Token is invalid. DeviceId = deviceId: \"345\" ";
        String s2 = "Token is invalid. DeviceId = deviceId: \"123\" ";
        String s3 = "Could not send Message.";

        System.out.println(computeLevenshteinDistance(s1, s2)); // s1 VS. s2
        System.out.println(computeLevenshteinDistance(s1, s3)); // s1 VS. s3
        System.out.println(computeLevenshteinDistance(s2, s3)); // s2 Vs. s3

    }
}