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

The following program finds the frequency, sorts it accordingly, and prints it.

Below is the output grouped by frequency:

0-10:
       The   2
       Is    4
11-20:
       Have 13
       Done 15

Here is my program:

package com.company;
import java.io.*;
import java.util.*;
import java.lang.*;

/**
 * Created by ayush on 12/3/17.
 */

public class Linked {

    public static void main(String args[]) throws IOException {

        BufferedReader br = new BufferedReader(
                new InputStreamReader(System.in));
        System.out.println("Enter the sentence");
        String st = br.readLine();
        st=st.trim();
        st = st + " ";
        int count = lengthx(st);
        System.out.println(count);
        String arr[] = new String[count];
        int p = 0;
        int c = 0;

        for (int i = 0; i < st.length(); i++) {
            if (st.charAt(i) == ' ') {
                arr[p] = st.substring(c,i);
                System.out.println(arr[p]);
                c = i + 1;
                p++;
            }
        }
        Map<String, Integer> map = new HashMap<>();

        for (String w : arr) {
            Integer n = map.get(w);
            n = (n == null) ? 1 : ++n;
            map.put(w, n);
        }
        for (String key : map.keySet()) {
            System.out.println(key + " = " + map.get(key));
        }

        Set<Map.Entry<String, Integer>> entries = map.entrySet();

        Comparator<Map.Entry<String, Integer>> valueComparator = new Comparator<Map.Entry<String,Integer>>() {

            @Override
            public int compare(Map.Entry<String, Integer> e1, Map.Entry<String, Integer> e2) {
                Integer v1 = e1.getValue();
                Integer v2 = e2.getValue();
                return v1.compareTo(v2); }
        };

        List<Map.Entry<String, Integer>> listOfEntries = new ArrayList<Map.Entry<String, Integer>>(entries);
        Collections.sort(listOfEntries, valueComparator);

        LinkedHashMap<String, Integer> sortedByValue = new LinkedHashMap<String, Integer>(listOfEntries.size());

        for(Map.Entry<String, Integer> entry : listOfEntries){

            sortedByValue.put(entry.getKey(), entry.getValue());
        }

        for(Map.Entry<String, Integer> entry : listOfEntries){

            sortedByValue.put(entry.getKey(), entry.getValue());
        }

        System.out.println("HashMap after sorting entries by values ");
        Set<Map.Entry<String, Integer>> entrySetSortedByValue = sortedByValue.entrySet();
        for(Map.Entry<String, Integer> mapping : entrySetSortedByValue){
            System.out.println(mapping.getKey() + " ==> " + mapping.getValue());
        }


    }

    static int lengthx(String a) {
        int count = 0;
        for (int j = 0; j < a.length(); j++) {
            if (a.charAt(j) == ' ') {
                count++;
            }
        }
        return count;
    }
}

Answer 2

public class TestSplit {

    public static void main(String[] args) {
            String input="Find the repeated word which is repeated in this string";
            List<String> output= (List) Arrays.asList(input.split(" "));

            for(String str: output) {
                    int occurrences = Collections.frequency(output, str);
                    System.out.println("Occurence of " + str+ " is "+occurrences);
            }

            System.out.println(output);
    }

}

Answer 3

Try this

public class Main
{

    public static void main(String[] args)
    {       
        String text = "the quick brown fox jumps fox fox over the lazy dog brown";
        String[] keys = text.split(" ");
        String[] uniqueKeys;
        int count = 0;
        System.out.println(text);
        uniqueKeys = getUniqueKeys(keys);

        for(String key: uniqueKeys)
        {
            if(null == key)
            {
                break;
            }           
            for(String s : keys)
            {
                if(key.equals(s))
                {
                    count++;
                }               
            }
            System.out.println("Count of ["+key+"] is : "+count);
            count=0;
        }
    }

    private static String[] getUniqueKeys(String[] keys)
    {
        String[] uniqueKeys = new String[keys.length];

        uniqueKeys[0] = keys[0];
        int uniqueKeyIndex = 1;
        boolean keyAlreadyExists = false;

        for(int i=1; i<keys.length ; i++)
        {
            for(int j=0; j<=uniqueKeyIndex; j++)
            {
                if(keys[i].equals(uniqueKeys[j]))
                {
                    keyAlreadyExists = true;
                }
            }           

            if(!keyAlreadyExists)
            {
                uniqueKeys[uniqueKeyIndex] = keys[i];
                uniqueKeyIndex++;               
            }
            keyAlreadyExists = false;
        }       
        return uniqueKeys;
    }
}

Output:

the quick brown fox jumps fox fox over the lazy dog brown
Count of [the] is : 2
Count of [quick] is : 1
Count of [brown] is : 2
Count of [fox] is : 3
Count of [jumps] is : 1
Count of [over] is : 1
Count of [lazy] is : 1
Count of [dog] is : 1

Answer 4

Simply use Java 8 Stream collectors groupby function:

    import java.util.function.Function;
    import java.util.stream.Collectors;  

    static String[] COUNTRY_NAMES 
  = { "China", "Australia", "India", "USA", "USSR", "UK", "China", 
  "France", "Poland", "Austria", "India", "USA", "Egypt", "China" };

    Map<String, Long> result = Stream.of(COUNTRY_NAMES).collect(
            Collectors.groupingBy(Function.identity(), Collectors.counting()));

Answer 5

class find
{
    public static void main(String nm,String w)
    {
        int l,i;
        int c=0;


        l=nm.length();String b="";

        for(i=0;i<l;i++)
        {
            char d=nm.charAt(i);
            if(d!=' ')
            {
                b=b+d;
            }
            if(d==' ')
            {
                if(b.compareTo(w)==0)
                {
                    c++;

                } 
               b="";           
            }        
        }       
        System.out.println(c);
    }
}

Answer 6

import java.io.*;

class Linked {

    public static void main(String args[]) throws IOException {

        BufferedReader br = new BufferedReader(
            new InputStreamReader(System.in));
        System.out.println("Enter the sentence");
        String st = br.readLine();
        st = st + " ";
        int a = lengthx(st);
        String arr[] = new String[a];
        int p = 0;
        int c = 0;

        for (int j = 0; j < st.length(); j++) {
            if (st.charAt(j) == ' ') {
                arr[p++] = st.substring(c,j);
                c = j + 1;
            }
        }
    }

    static int lengthx(String a) {
        int p = 0;
        for (int j = 0; j < a.length(); j++) {
            if (a.charAt(j) == ' ') {
                p++;
            }
        }
        return p;
    }
}