have a  running  Exception

Java on Mobile Devices J2ME
#1

when it run,it say Exception following:
java.lang.NullPointerException

at javax.microedition.lcdui.game.Sprite.(+17)
at myprojectb.MyGameWithSpriteCanvas1.createCharacter(+37)

  at myprojectb.MyGameWithSpriteCanvas1.<init>(+48)

  at myprojectb.MyGame.startApp(+15)

  at javax.microedition.midlet.MIDletProxy.startApp(+7)

  at com.sun.midp.midlet.Scheduler.schedule(+270)

  at com.sun.midp.main.Main.runLocalClass(+28)

  at com.sun.midp.main.Main.main(+116)

why?

#2

Why? Because you have some null object when you call the Sprite constructor. Looking at the Sprite documentation, a NullPointerException is thrown from the constructor because either the image for the sprite is null, or in the case of the copy constructor the other sprite is null.

shmoove

#3

Strart by puting a bunch of System.out.printlns in your

myprojectb.MyGameWithSpriteCanvas1.createCharacter(+37)

method. This is one of the only ways I find null variables and exceptions. I’ve found debuggers to be less than adequate, but it’s been a while since I used one with J2ME, maybe they’ve improved?

Wood