看似好的代码获得NullPointerException？

Question

I'm having an issue where I have a player object that I'm trying to send to a method, and it doesn't work. As far as I can tell, however, it should. Any ideas?

The line on which I find the error:

keybl.playerUpdate(player);

Wherein "keybl" is a KeyListener that is initialized and is functioning in code before this runs, "playerUpdate" is a method seen below, and "player" is a Player object which is, in fact, initialized properly.

public void playerUpdate(Player somePlayer) {

    user = somePlayer;

}

Wherein "user" is a class variable of type "Player" that is set to a different player object when this is run.

Any ideas?

Answer 1

If the exception is on this line:

keybl.playerUpdate(player);

then it must be that keybl is null. Add one System.out.println("keybl: " + keybl); before this line and you should see it printing null at some point (or to be precise - before the exception is thrown).