#1 Null pointer exception

[Barnet Wagman]

I just built JPerfAnaly from CVS sources (using the
makefile). I started app with
java -Xmx96m -classpath net.javalinux.JPerfAnaly xx.prof

where xxx.prof was produced runing the IBM 1.3.1
version of Java for Linux

I get

Exception in thread "main" java.lang.NullPointerException
at net.javalinux.SelectMethod.<init>(SelectMethod.java:41)
at
net.javalinux.JPerfAnal.<init>(JPerfAnal.java(Compiled
Code))
at net.javalinux.JPerfAnal.main(JPerfAnal.java:320)

Is this a known bug?

Regards,

Barnet Wagman
wagman@enteract.com

[Nathan Meyers]

Logged In: YES
user_id=413143

Could you supply xxx.prof?

JPerfAnal isn't smart about checking whether the file has
any real data, and could fail in this way if there are no
traces. Unfortunately, some JVMs don't produce any useful
analysis data with hprof. Getting my hands on that file
would help me ascertain if that's the case or we have a real
bug.

[Anders Eriksson]

Logged In: YES
user_id=295842

Hello,

this happens when you do not have cpu=samples as hprof
option. Turn that on and it works.

/Anders

[Kurt Werle]

Logged In: YES
user_id=6449

Please give the user some kind of information when this exception
happens so they don't have to look here!