Any improvements?

package hangman;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Hangman {
    private final String word = getRandomWordFromFile();
    private final Scanner input = new Scanner(System.in);
    private final StringBuilder maskedSentence = new StringBuilder("-".repeat(word.length()));

    Hangman() {
        System.out.println(maskedSentence);
    }

    private String getRandomWordFromFile() {
        Map<Integer, String> words = new HashMap<>();
        String line;
        try {
            File file = new File("src/main/resources/words.txt");
            FileReader fileReader = new FileReader(file);
            BufferedReader bufferedReader = new BufferedReader(fileReader);
            int LINES = 100;
            for (int i = 0; i < LINES; i++) {
                line = bufferedReader.readLine();
                words.put(i, line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return words.get((int) (Math.random() * words.size()));
    }

    public void hangmanGame() {
        StringBuilder incorrectCharsEntered = new StringBuilder();
        while (incorrectCharsEntered.length() != doubleTheWordLength()) {
            StringBuilder correctCharsEntered = new StringBuilder();
            String human = input.next();
            correctCharsEntered.append(human);

            if (!hasCorrectCharactersEntered(correctCharsEntered)) {
                incorrectCharsEntered.append(correctCharsEntered.charAt(correctCharsEntered.length() - 1));
                correctCharsEntered.deleteCharAt(correctCharsEntered.length() - 1);
                System.out.println("Letters attempted " + incorrectCharsEntered);
            } else {
                for (int i = 0; i < word.length(); i++) {
                    if (isLetterMatching(correctCharsEntered, i)) {
                        maskedSentence.setCharAt(i, correctCharsEntered.charAt(correctCharsEntered.length() - 1));
                    }
                }
            }
            if (maskedSentence.toString().equals(word) || human.equals(word)) {
                System.out.println("Congratulations you won");
                break;
            }
            System.out.println("So far " + maskedSentence);
        }
        System.out.println("The word was " + word);
    }

    private boolean isLetterMatching(StringBuilder correctCharsEntered, int i) {
        return word.charAt(i) == correctCharsEntered.charAt(correctCharsEntered.length() - 1);
    }

    private boolean hasCorrectCharactersEntered(StringBuilder correctCharsEntered) {
        return word.contains(correctCharsEntered);
    }

    private int doubleTheWordLength() {
        return word.length() * 2;
    }
}