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Java

Arshan Khanifar
Arshan Khanifar
11,497 Points
Posted by 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:

java.lang.NullPointerException

2 Answers

Nicolas Hampton
Nicolas Hampton
44,638 Points

answer = mAnswer; should be mAnswer = answer;

Try that.