Hey there guys I'm new to java OOP and im not very good at it at all. I have a uni assignment due in soon which i mostly completed but I'am stuck on this questions which ask us to make a guessword game. this is the problem

Problem 3 – The Guess-a-Word Game (15% implementation, 10%
design, code, layout and comments)
The guess-a-word game, as the name suggests, is a game of guessing words. You will be playing
this game with the computer in charge of the game. Suppose the word you have to guess is:
PROGRAMMING
The computer would start by displaying the word with each letter replaced by an asterisk:

***********
Number of mistakes = 0
Wrongly guessed letters = “
Letters available = “ABCDEFGHIJKLMNOPQRSTUVWXYZ

That display means that so far you have not made any mistakes and the set of wrongly guessed
letters is empty.

You are then asked to play a letter. Suppose you play letter “M. The computer would display:

******MM***
Number of mistakes = 0
Wrongly guessed letters = “
Letters available = “ABCDEFGHIJKLNOPQRSTUVWXYZ

Next suppose you play letter “E which is not one of the letters of the word. Then the computer
would display:
******MM***
Number of mistakes = 1
Wrongly guessed letters = “E
Letters available = “ABCDFGHIJKLNOPQRSTUVWXYZ

And so on until you successfully guess all the letters in the word, or until you make nine
mistakes.

You are required to do the following:

• First, design and create a class called GuessWord to represent a game. (If you freeze the
game at a point in time and observe its state, then what do you see? What would constitute
the state of the game? How would the game change its state?)

• Second, provide a text-based interface program called GuessWordTest that will allow the
user to play the game once. The text-based interface program should use the class you create
in step 1. The interface will ask for a word to guess (that is entered at the keyboard), then
the dialog between the user and the program is similar to that described above.

And here is the coding i have done so far

public class GuessWord
{
private String word;
private char letterguessed;
private int numberOfMistakes;
private char wronglyGuessLetters;
private String[] hiddenWord = new String[word.length()];
private char[] lettersAvalible = new char[26];


public GuessWord(String word, char letterguessed)

{
this.letterguessed = letterguessed;
this.word = word;
numberOfMistakes = 0;
wronglyGuessLetters = (char)0;
for( int i = 0; i < word.length(); i++)
{
hiddenWord[i] = "*";
}
for( int j = 0; j < lettersAvalible.length; j++ )
{
lettersAvalible[j] = (char)('A' + j);
}
}

public void displayWord()

{
hiddenWord = new String[word.length()];
for ( int i = 0; i < hiddenWord.length; i++)
{
if ( letterguessed != word.charAt(i) )
{
hiddenWord[i] = "*";
}
else
{
hiddenWord[i] += (char)letterguessed;
}

}
}

public void checkGuess(int count)

{
for ( int i = 0; i <= word.length(); i++)
{

if ( letterguessed != word.charAt(i) )
{
count++;
}

if ( count == word.length() )
{
numberOfMistakes++;
wronglyGuessLetters += (char)letterguessed;
}

}
if( numberOfMistakes == 9 )
{
System.out.println("\nGAME OVER");
}

}

public void lettersLeft()

{
for ( int i = 0; i < lettersAvalible.length; i++ )
{
if ( letterguessed == lettersAvalible[i] )
{
lettersAvalible[i] = (char)' ';
}

}
}


public String toString()

{
return( hiddenWord + "\nNumber of mistakes = " + numberOfMistakes + "\nWrongly guessed letters = "
+ wronglyGuessLetters + "\nLetters available = " + lettersAvalible);
}


}

Then my text based interface is

import java.util.*;
public class GuessWordTest
{
public static void main(String[] args)
{
System.out.println("Please insert a word to be guessed");
Scanner keyboard = new Scanner(System.in);
int i = 0;
String word = keyboard.nextLine();
System.out.println("please guess a letter");
char letterguessed = (char)keyboard.nextLine().charAt(0);
GuessWord test = new GuessWord(word, letterguessed);
do
{
test.displayWord();
test.checkGuess(0);
test.lettersLeft();
test.toString();
i++;
System.out.println("Guess another letter");
}while( word != "programing");
System.out.print("GAME OVER, thanks for using!");


}
}

defined class (GuessWord) compiles with no error, so i'am no sure wat is wrong PLEASE ANYBODY HELP THIS NOOB OUT, i appreciate anyone who even bothered read my problem

OK, as i was bored i had a quick look.

In GuessWord.java you have :

private String[] hiddenWord = new String[word.length()];

This is a instance variable which is created as the constructor executes but BEFORE any parameters have been initialised, so 'word' does not exist here. [null exception]

Then later you have :

for ( int i = 0; i <= word.length(); i++)
{
    if ( letterguessed != word.charAt(i) )
    {
        count++;
    }
}

If you have a String with 4 characters, the indexes to these characters start at 0 (so 0...3). [out-of-bounds exception]

These are two fatal errors.

Then in GuessWordTest you have :

do
{
    test.displayWord();
    test.checkGuess(0);
    test.lettersLeft();
    test.toString();
    i++;
    System.out.println("Guess another letter");
} while( word != "programing");

Ehh, it would be nice if i could actually enter another letter.

Hope this points you in the right direction.

K, thanks for the reply mate and help i appreciate it

ok ive adjusted my code, just note that i made copys of the original files and renamed the filenames and classes.

public class lele
{
   private String word;
   private char letterguessed;
   private int numberOfMistakes;
   private char wronglyGuessLetters;
   private String[] hiddenWord;
   private char[] lettersAvalible = new char[26];

   public lele(String word, char letterguessed, String[] hiddenWord)
   {
      this.letterguessed = letterguessed;
      this.word = word;
      numberOfMistakes = 0;
      wronglyGuessLetters = (char)0;
      hiddenWord = new String[word.length()];
      for( int j = 0; j < lettersAvalible.length; j++ )
      {
         lettersAvalible[j] = (char)('A' + j);
      }
   }
   public void displayWord()
   {
      for ( int i = 0; i < hiddenWord.length; i++)
      {
         if ( letterguessed != word.charAt(i) )
         {
            hiddenWord[i] = "*";
         }
         else
         {
            hiddenWord[i] += letterguessed;
         }
      }
   }
   public void checkGuess(int count)
                                          
   {
      for ( int i = 0; i < word.length(); i++)
      {
         if ( letterguessed != word.charAt(i) )
         {
            count++;
         }
         if ( count == word.length() )
         {
            numberOfMistakes++;
            wronglyGuessLetters += (char)letterguessed;
         }
      }
      if( numberOfMistakes == 9 )
      {
         System.out.println("\nGAME OVER");
      }
   }
   public void lettersLeft()
   {
      for ( int i = 0; i < lettersAvalible.length; i++ )
      {
         if ( letterguessed == lettersAvalible[i] )
         {
            lettersAvalible[i] = (char)' ';
         }
      }
   }

   public String toString()
   {
      return( hiddenWord + "\nNumber of mistakes = " + numberOfMistakes + "\nWrongly guessed letters = "
             + wronglyGuessLetters + "\nLetters available = " + lettersAvalible);
     }
}

And the other....

import java.util.*;
public class lala
{
   public static void main(String[] args)
   {
      System.out.println("Please insert a word to be guessed");
      Scanner keyboard = new Scanner(System.in);
      String word = keyboard.nextLine();
      System.out.println("please guess a letter");
      char letterguessed = keyboard.next().charAt(0);
      int e = word.length();
      int counter = 0;
      String[] hiddenWord = new String[e];
      for(int z = 0; z < hiddenWord.length; z++)
      {
         hiddenWord[z] = "*";
      }
      lele test = new lele(word, letterguessed, hiddenWord);
      do
      {
         test.displayWord();
         test.checkGuess(0);
         test.lettersLeft();
         test.toString();
         letterguessed = keyboard.next().charAt(0);
         System.out.println("Guess another letter");
         counter++;
      }while( hiddenWord[counter] != word);
      System.out.print("GAME OVER, thanks for using!");

   }
}

Im still having some NullPointerException errors with hiddenWord and within the second code im having trouble with the condition in my while loop comparing an char array with a String word, and ideas how to go about this? thx again

OK, lets see. Starting from the main method you input a word and a letter and then for some reason create a array of strings, word.length strings long, and each string is set to "*".

I expect you want an array of char with each char set to '*' for display purposes.

In the lele class you declare a hiddenword instance variable and also use hiddenword as a parameter. Makes it very tricky to follow which variable you are using.

for checking chars in a char array to a string it would look someting like :

String word = "String To Test";
char[] characters = new char[4];

characters[0] = 'a';
characters[1] = 'i';
characters[2] = 'e';
characters[3] = 'o';

for (int count = 0; count < characters.size; count++)

Edited 3 Years Ago by Dani: Formatting fixed

Oops, wrong key, we continue :

for (int count = 0; count < characters.length; count++) {
    for (int c2 = 0; c2 < word.length(); c2++) {
        if (word.charAt(c2) == characters[count]) {
            System.out.println("Found");
        }
    }
}

Crude but works.

Have a try again.
Good luck.

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