That would negate the entire purpose of the java
development program. Notice how you asked the question,
"...since most...!" That should indicate to you that not
all OS's are windows  platforms and the purpose of
java is to provide a language that can be
interpreted(or used) by all OS's. Just because a person can
program doesn't mean they will be using a computer that
will be of the Intel based family of mpu's. By doing
what you suggest would restrict many programmers work
to that platform, not to mention the compatibility
of browsers and OS's to decypher the programmers
intent.

That would negate the entire purpose of the java
development program. Notice how you asked the question,
"...since most...!" That should indicate to you that not
all OS's are windows  platforms and the purpose of
java is to provide a language that can be
interpreted(or used) by all OS's. Just because a person can
program doesn't mean they will be using a computer that
will be of the Intel based family of mpu's. By doing
what you suggest would restrict many programmers work
to that platform, not to mention the compatibility
of browsers and OS's to decypher the programmers
intent.

We can still use standard java  through JVM.
Because some Java programs are just like windows
applications without involving multiple platforms, a compiled
version for windows  doesn't hurt, it only provides users
with one more choice. I'd like to know how much
performance gain a compile  version can offer, if someone
could do a benchmark test.

Actually, the reason why you don't see compilers
for Java is that the language is not yet
stable.By the time somebody creates a Java Windows
compiler, a new version  pops out of the hopper at Sun. It
takes a lot of time and testing to get one done
correctly, so it is just not yet economically profitable.
You can find some compilers around, but if you look
closely, you'll see they are mostly based upon one of the
older JRE's.In one benchmark comparison at
JavaOne, a presenter showed that compiled  C++ code ran 6
times faster over Java 1.2 for the simple stuff. As
more complex operations were invoked, C++ was running
at many multiples faster. The JIT compilers have
reduced some of the apparent slowness of Java when
multiple passes through the same code are
considered.If you really need the speed, you might consider
writing your stuff in Java and then running a Java to C++
converter. It's a lot of steps to go through,
though.

go here http://gcc.gnu.org/java/
gcj is what you are looking for