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Java Java Objects Creating the MVP Remaining Tries

Luan Torres
Luan Torres
1,172 Points
Posted by Luan Torres
Luan Torres
1,172 Points

Exception in thread "main" java.lang.NullPointerException

Exception in thread "main" java.lang.NullPointerException
at Game.getRemainingTries(Game.java:22)
at Hangman.main(Hangman.java:7)

at Game.getRemainingTries(Game.java:22) : public int getRemainingTries() { return MAX_MISSES - misses.length(); }

at Hangman.main(Hangman.java:7): while (game.getRemainingTries() > 0){ prompter.displayProgress(); prompter.promptForGuess(); }

anybody knows why it is not working?

2 Answers

Linda de Haan
Linda de Haan
12,413 Points
Linda de Haan
Linda de Haan
12,413 Points

A NullPointerException is thrown when a method is being used on a variable that hasn't been initialized. In this case the getRemainingTries() method is trying to use the length() method on the misses variable, but it hasn't been initialized, so it is null.

You can solve this by setting a default value in the constructor like this:

misses = "";