On Thu, 06 Jan 2011 15:24:34 -0800, markspace wrote:
On 1/6/2011 3:05 PM, Julien ?LIE wrote:
Suppose I have test.java and I want to compile it with Java SE 6 Update
23 on different OSes and hardwares; would it generate the same
test.class file ("the same" means that it is exactly the same file --
same MD5 checksum for instance).
I think everyone has consistently been saying 1) we don't know, and 2)
Sun/Oracle doesn't seem to make any such guarantee.
I think you are likely to get exactly the same byte codes, but I
wouldn't count on it. If your process will absolutely break due to
different byte codes, make a more robust process.
But why would it break anyway? Maybe it's a bad comparison, but I compare
that to, say, compiling C code with different C compilers or with
different
optimization options of the same compiler. The resulting machine code
is in
no doubt different, but it still does the same thing at the end of the
day.
The one possibility of "breakage" would be for example if you're working
with some highly memory limited machine (some MCU for example) when with
some compiler options the resulting machine code would be too large to
fit
inside the machine's memory or it would perform faster or slower (or even
break your process) with different compiler options..
However, I can't see a similar situation happening with Java. In other
words, I don't see the importance of thinking about that stuff when
working
with Java. So my question to Julien is: why do you care about it?