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Java

iftekhar uddin
iftekhar uddin
4,194 Points
Posted by iftekhar uddin
iftekhar uddin
4,194 Points

Exception in thread "main" java.lang.NullPointerException

Problem: I'm getting this error

Exception in thread "main" java.lang.NullPointerException
at com.teamtreehouse.model.SongBook.addSong(SongBook.java:14)
at Karaoke.main(Karaoke.java:14)

My Code

I have looked at SongBook.java line 14 and unless I'm blind it's exactly how it is with craig's code in the video "building the model"

thanks for taking the time reading and responding to my question. Much Appreciated.

1 Answer

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

iftekhar;

In SongBook.java you have 

public void SongBook()  {
   mSongs = new ArrayList<Song>();
}

Remove the void from that method, as in the videos, and your code works great. Remember that in Java constructors don't have explicit return types in their method signatures.

Happy coding,
Ken

iftekhar uddin
iftekhar uddin
4,194 Points
iftekhar uddin
iftekhar uddin
4,194 Points

Oh my god I feel so stupid XD. I tunnel visioned on that line so much that I didn't even realize that constructor was messed up. Thanks =)

Ken Alger
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Don't feel stupid. That's part of the learning process.