Shitty hangman

HangMan.java

import java.util.*;

public class HangMan {
    private static String[] words = {
        "motherboard", "case", "powersupply", "harddrive", "mouse", "keyboard", "peripheral",
        "graphicscard", "processor", "latency", "ping", "gaming", "resolution", "watercooling",
        "cache", "memory", "chipset", "intel", "notebook", "desktop", "aliasing" };
        
    public static void main(String[] args) {
        Random rand = new Random();
        String userChoice = 
            readLine("Welcome to a game of hangman!\nDo you want to play? (Y/N): ");
        
        int gameCount = 0;
        int lostGames = 0;
        while (!userChoice.equalsIgnoreCase("n")) {
            switch(userChoice.toLowerCase()) {
                case "y":
                    String word = words[rand.nextInt(words.length)];
                    if (!playGame(word, 6))
                        lostGames++;
                    
                    gameCount++;
                    break;
                default:
                    System.out.println("Sorry, didn't understand that.");
                    break;
            }
            
            userChoice = 
                readLine("You have played " + gameCount + " games. Do you want to play again?");
        }
        
        System.out.println("Thanks for playing");
    }
    
    private static Boolean playGame(String word, int guessesLeft)  {
        String hiddenWord = initHiddenWord(word);
        while(guessesLeft > 0)
        {
            String inChar = readLine("Your guess: ");
            while(true) {
                if (inChar.length() > 1)
                    inChar = readLine("You can only guess one letter at a time");
                if (inChar.length() == 1) break;
            }
            char ch = Character.toLowerCase(inChar.charAt(0));
            if (!letterOk(word, ch))
                guessesLeft--;
            else
                hiddenWord = replaceLetters(word, hiddenWord, ch);
            if (hiddenWord.equals(word)) {
                System.out.println("You guessed the word: " + word);
                System.out.println("You win");
                return true;
            }
            System.out.println("The word now looks like this: " + hiddenWord);
            System.out.println("You have " + guessesLeft + " guesses left.");
        }
        
        return false;    
    }
    
    private static String initHiddenWord(String word) {
        String result = "";
        for(int i = 0; i < word.length(); i++)
            result = result + "-";
        return result;
    }
    
    private static Boolean letterOk(String word, char guess) {
        if (word.indexOf(guess) == -1) {
            System.out.println("There are no " + guess + "'s in the word.");
            return false;
        } else {
            System.out.println("Found " + guess + "'s in the word.");
            return true;
        }
    }
    
    private static String replaceLetters(String word, String hiddenWord, char guess) {
        for(int i = 0; i < word.length(); i++) {
            if (guess == word.charAt(i)) {
                if (i > 0) hiddenWord = hiddenWord.substring(0, i) + guess + hiddenWord.substring(i + 1);
                if (i == 0) hiddenWord = guess + hiddenWord.substring(1);
            }
        }
        return hiddenWord;
    }
    
    static Scanner scan = new Scanner(System.in);
    private static String readLine(String consoleOutput) {
        System.out.println(consoleOutput);
        return scan.next();
    }
}