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Start your free trialJonathan Mitten
Courses Plus Student 11,197 PointsNullPointerException at Game.getRemainingTries line 35
As far as I can tell, I've correctly set up all the code, and reviewed videos and other code samples on this course to ensure I have everything written correctly.
However, when I run Hangman, I immediately get:
Exception in thread "main" java.lang.NullPointerException
at Game.getRemainingTries(Game.java:35)
at Prompter.play(Prompter.java:11)
at Hangman.main(Hangman.java:8)
Which refers to :
public int getRemainingTries() {
return MAX_MISSES - mMisses.length();
}
I'm not sure how to debug this within the Treehouse Workspaces, or if it's a workspaces issue that's throwing the error.
1 Answer
Seth Kroger
56,413 PointsOne of the variables in getRemainingTries() is uninitialized. It's most likely mMisses, which would cause calling length() on the null variable to throw the exception. You probably forgot to set it to an empty string in the constructor.
Jonathan Mitten
Courses Plus Student 11,197 PointsThat's what it was. Thanks!
Jennifer Leap
21,702 PointsJennifer Leap
21,702 PointsThis suggest you have a null object somewhere--maybe a variable that hasn't been initialized? It's difficult to tell without seeing your full code.