Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/**
 Copyright 2016, Yahoo Inc.
 Licensed under the terms of the Apache License 2.0. See LICENSE file at the project root for terms.
 **/

import java.util.ArrayList;
import java.util.List;

public class Main {
    /** @param phrase1
     * @param phrase2
     * @return lexical similarity value in the range [0,1] */
    public static double lexicalSimilarity(String phrase1, String phrase2) {
        List<String> pairs1 = wordLetterPairs(phrase1.toUpperCase());
        List<String> pairs2 = wordLetterPairs(phrase2.toUpperCase());
        int intersection = 0;
        int union = pairs1.size() + pairs2.size();
        for (int i = 0; i < pairs1.size(); i++) {
            String pair1 = pairs1.get(i);
            for (int j = 0; j < pairs2.size(); j++) {
                String pair2 = pairs2.get(j);
                if (pair1.equals(pair2)) {
                    intersection++;
                    pairs2.remove(j);
                    break;
                }
            }
        }
        return (2.0 * intersection) / union;
    }

    /**  @param str
     *  @return an ArrayList of 2-character Strings. */
    private static List<String> wordLetterPairs(String str) {
        List<String> allPairs = new ArrayList<String>();
        // Tokenize the string and put the tokens/words into an array
        String[] words = str.split("\\s");
        // For each word
        for (int w = 0; w < words.length; w++) {
            // Find the pairs of characters
            String[] pairsInWord = letterPairs(words[w]);
            for (int p = 0; p < pairsInWord.length; p++) {
                allPairs.add(pairsInWord[p]);
            }
        }
        return allPairs;
    }

    /** @param str
     *  @return an array of adjacent letter pairs contained in the input string */
    private static String[] letterPairs(String str) {
        if (str.length() < 2) {
            return new String[0];
        }
        int numPairs = str.length() - 1;
        String[] pairs = new String[numPairs];
        for (int i = 0; i < numPairs; i++) {
            pairs[i] = str.substring(i, i + 2);
        }
        return pairs;
    }
}