Calculating frequency of each word in a sentence in java

Question

I am writing a very basic java program that calculates frequency of each word in a sentence so far i managed to do this much

import java.io.*;

class Linked         


        

Answer 1

import java.util.*;

public class WordCounter {

    public static void main(String[] args) {

        String s = "this is a this is this a this yes this is a this what it may be i do not care about this";
        String a[] = s.split(" ");
        Map<String, Integer> words = new HashMap<>();
        for (String str : a) {
            if (words.containsKey(str)) {
                words.put(str, 1 + words.get(str));
            } else {
                words.put(str, 1);
            }
        }
        System.out.println(words);
    }
}

Output: {a=3, be=1, may=1, yes=1, this=7, about=1, i=1, is=3, it=1, do=1, not=1, what=1, care=1}

Answer 2

package naresh.java;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Set;

public class StringWordDuplicates {

    static void duplicate(String inputString){

        HashMap<String, Integer> wordCount = new HashMap<String,Integer>();
        String[] words = inputString.split(" ");

        for(String word : words){
            if(wordCount.containsKey(word)){
                wordCount.put(word, wordCount.get(word)+1);             
            }
            else{
                wordCount.put(word, 1);
            }
        }
        //Extracting of all keys of word count
        Set<String> wordsInString = wordCount.keySet();

        for(String word : wordsInString){
            if(wordCount.get(word)>1){
                System.out.println(word+":"+wordCount.get(word));
            }
        }

    }
    public static void main(String args[]){
        duplicate("I am Java Programmer and IT Server Programmer with Java as Best Java lover");

    }
}

Answer 3

From Java 10 you can use the following:

import java.util.Arrays;
import java.util.stream.Collectors;

public class StringFrequencyMap {
    public static void main(String... args){
        String[] wordArray = {"One", "One", "Two","Three", "Two", "two"};
        var freq = Arrays.stream(wordArray)
                         .collect(Collectors.groupingBy(x -> x, Collectors.counting()));
        System.out.println(freq);
    }
}

Output:

{One=2, two=1, Two=2, Three=1}

Answer 4

    String s[]=st.split(" ");
    String sf[]=new String[s.length];
    int count[]=new int[s.length];
    sf[0]=s[0];
    int j=1;
    count[0]=1;
    for(int i=1;i<s.length;i++)
    {
        int t=j-1;
        while(t>=0)
        {

            if(s[i].equals(sf[t]))
            {
                count[t]++;
                break;
            }
            t--;
        }
        if(t<0)
        {
            sf[j]=s[i];
            count[j]++;
            j++;
        }
    }

Answer 5

In Java 8, you can write this in two simple lines! In addition you can take advantage of parallel computing.

Here's the most beautiful way to do this:

Stream<String> stream = Stream.of(text.toLowerCase().split("\\W+")).parallel();

Map<String, Long> wordFreq = stream
     .collect(Collectors.groupingBy(String::toString,Collectors.counting()));

Answer 6

public class wordFrequency {
    private static Scanner scn;

    public static void countwords(String sent) {
        sent = sent.toLowerCase().replaceAll("[^a-z ]", "");
        ArrayList<String> arr = new ArrayList<String>();
        String[] sentarr = sent.split(" ");
        Map<String, Integer> a = new HashMap<String, Integer>();
        for (String word : sentarr) {
            arr.add(word);
        }
        for (String word : arr) {
            int count = Collections.frequency(arr, word);
            a.put(word, count);
        }
        for (String key : a.keySet()) {
            System.out.println(key + " = " + a.get(key));
        }
    }

    public static void main(String[] args) {
        scn = new Scanner(System.in);
        System.out.println("Enter sentence:");
        String inp = scn.nextLine();
        countwords(inp);
    }

}