Java Program to Find the Most Repeated Word in a Text File

Last Updated : 20 Feb, 2023

Map and Map.Entry interface will be used as the Map interface maps unique keys to values. A key is an object that is used to retrieve a value at a later date. The Map.Entry interface enables you to work with a map entry. Also, we will use the HashMap class to store items in "key/value” pairs and access them by an index of another type.

Illustration:

Suppose the content of the sample text file is as follows:

Input: A text file containing sequence of arbitrary words

“How to count the number of occurrence of each word? How to count number or each word in string. Calculating frequency of each word in a sentence in java.”

Output: List of words that have the maximum occurrence
in = 3
each = 3
of = 3
to = 3

Implementation: Sample file input image is as follows:

Example

Java

// Java Program to Find the
// Most Repeated Word in a Text File

// Importing File classes
import java.io.File;
import java.io.FileNotFoundException;
// Importing Map and HashMap class from
// java.util package
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
// Importing Scanner class to
// take input from the user
import java.util.Scanner;

// Class 
// To find maximum occurrences
public class GFG {

    // Method 1 - getWords()
    // Reading out words from the file and
    // mapping key value pair corresponding to
    // each different word
    static void getWords(String fileName,
                         Map<String, Integer> words)
        throws FileNotFoundException
    {
        // Creating a Scanner class object
        Scanner file = new Scanner(new File(fileName));

        // Condition check using hasNext() method which
        // holds true till there is word being read from the
        // file. 
      // As the end of file content,condition violates
        while (file.hasNext()) {

            // Reading word using next() method
            String word = file.next();

            // Frequency count variable
            Integer count = words.get(word);

            // If the same word is repeating
            if (count != null) {

                // Incrementing corresponding count by unity
                // every time it repeats
              // while reading from the file
                count++;
            }
            else

                // If word never occurred after occurring
                // once, set count as unity
                count = 1;
            words.put(word, count);
        }

        // Close the file and free up the resources
        file.close();
    }

    // Method 2 - getMaxOccurrence()
    // To get maximum occurred Word
    static int getMaxOccurrence(Map<String, Integer> words)
    {
        // Initially set maximum count as unity
        int max = 1;

        // Iterating over above Map using for-each loop
        for (Entry<String, Integer> word :
             words.entrySet()) {

            // Condition check
            // Update current max value  with the value
            // exceeding unity in Map while traversing
            if (word.getValue() > max) {
                max = word.getValue();
            }
        }

        // Return the maximum value from the Map
        return max;
    }

    // Method 3
    // Main driver method
    public static void main(String[] args)
        throws FileNotFoundException
    {
        // Creating an object of type Map
        // Declaring object of String and Integer types
        Map<String, Integer> words
            = new HashMap<String, Integer>();

        // Retrieving the path as parameter to Method1()
        // above to get the file to be read
        getWords("C:\\Users\\dell\\sample.txt", words);

        // Variable holding the maximum
        // repeated word count in a file
        int max = getMaxOccurrence(words);

        // Traversing using for each loop
        // Creating a set out of same elements
        // contained in a HashMap
        for (Entry<String, Integer> word :
             words.entrySet()) {

            // Comparing values using geValue() method
            if (word.getValue() == max) {

                // Print and display word-count pair
                System.out.println(word);
            }
        }
    }