java compilling and running

[hari kt]

Hi
 I am a student.
I used to compile java from windows by
>javac filename.java
and run it by
>java filename

Now I like to know how to compile java in linux so i downloaded sun
javas compiller and compiller but my fedora core 2 is telling errors
by trying i found the in built command gcj
so i compilled using 
#gcj -c -g -O filename.java
There was no errors
#gcj --main=filename -o filename filename.o
There was also no errors
Now i dont know how to run it

I tried these
#./filename
#./filename.o
#gcjh filename
When i typed gcjh filename it says error abt swing applet
Plz help me 
If you need any datas from me ask me and help me 
With lots of thanks

-- 
Hari K T

S5 I T

CUIET