The Frequency program outputs the frequency of each word in input file sorted alphabetically, and outputs the word with greatest frequency

Frequency.java

/*
 * The Frequency program outputs the frequency of each word in input 
 * file sorted alphabetically, and outputs the word with greatest frequency
 */

import java.io.*;
import java.util.*;

public class Frequency {
    public static void main(String[] args) throws Exception {
        Scanner fileName = new Scanner(System.in);
        System.out.print("Please enter the name of the input file: ");
        Scanner inputFile = new Scanner(new File(fileName.nextLine()));
        fileName.close();

        String maxKey = null;
        int maxFreq = 0;
        TreeMap<String, Integer> map = new TreeMap<>();

        while (inputFile.hasNext()) {
            String word = inputFile.next();
            Integer count = map.get(word);
            map.put(word, (count == null) ? 1 : count + 1);
        }
        inputFile.close();

        for (String key : map.keySet()) {
            int freq = map.get(key);
            System.out.println("Word: " + key + ", Frequency: " + freq);
            if (freq > maxFreq) {
                maxFreq = freq;
                maxKey = key;
            }
        }
        System.out.println("\nMaximum: " + maxKey + ", " + maxFreq);
    }
}