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Java Java Objects Creating the MVP Remaining Tries

Posted by Harrison Fabian
Harrison Fabian
692 Points

Can't run code because of these apparent exceptions?

Exception in thread "main" java.lang.NullPointerException at Game.getCurrentProgress(Game.java:24) that is my output error, now for the code it's referring to:

class Game { private String answer; private String hits; private String misses;

public Game(String Answer) { this.answer = answer; hits = ""; misses = ""; }

public boolean applyGuess(char letter) { boolean isHit = answer.indexOf(letter) != -1; if (isHit) { hits += letter; } else { misses += letter; } return isHit; }

public String getCurrentProgress() { String progress=""; for (char letter : answer.toCharArray()) { char display = '-'; if (hits.indexOf(letter) != -1) { display = letter; } progress+=display; } return progress; }

}

Is there anything I'm visibly doing wrong, or what?

1 Answer

Christof Baumgartner
Christof Baumgartner
20,864 Points
Christof Baumgartner
Christof Baumgartner
20,864 Points

So at least one problem is in you constructor. You wrote Answer with an capital A in the parameters, but with a lower a in the function body. Here is correct version:

    public Game(String answer) {
        this.answer = answer; 
        hits = ""; 
        misses = "";
    }

Does this solve your problem?

Harrison Fabian
Harrison Fabian
692 Points

Thank you so much, I was getting so frustrated because I couldn't tell what was wrong.