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Arshan Khanifar
Arshan Khanifar
11,497 Points

what's NullPointerException error?

I'm making the hangman game myself and I'm following along with the video, but I don't know where my problem is :

this is my code:

public class Game { private String mAnswer; private String mHits; private String mMisses;

public Game(String answer) { answer = mAnswer; mHits = ""; mMisses = "";


public boolean applyGuess(char letter) {

boolean isHit = mAnswer.indexOf(letter) >=0 ; 
if (isHit) {
  mHits += letter; 
}else {
  mMisses += letter;

return isHit; 



and I open up the repl and load the game. and I make the game class, but when I'm using the method applyGuess i get this error:


2 Answers

Nicolas Hampton
Nicolas Hampton
44,638 Points

answer = mAnswer; should be mAnswer = answer;

Try that.