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pluto_24 (1) [Avatar] Offline
#1
Hi everyone. I am a student doing my project using this book and the book's source code. i have modified some parts of the code, but i am stuck in the model.sendPresence part. I have created a java file with my own model.sendPresence method. But when i press my button to send the presence, i have got a nullpointerexception returned. I have tried the book's Rosterclient.java and although that works, i still do not understand what is wrong. Thank you.