Same source always makes same .class file ?

Compiling same source code will result always in same .class file ? (off course using the same compiler).
I've seen a site that says the compiler puts a timestamp in the class file. So compiling again at a different time will not result in same .class file.

_cristi_ wrote:
I have tested, so far class files seem to be identical.
But in a large project there might be cases when they differ, that's why I've asked, I can't be 100% sure based on a few tests.
Certainly won't be based on timestamp then.
I need this to extract only the class files that have been changed in order to deploy them.
There is a jar compare tool out there that first decompiles the classes and then compares the resulted text. They say this is necesarry because of timestamp in class files. Link: http://www.extradata.com/products/jarc/
I suggest you ask them to document the claim about the timestamp. They are selling a product and thus the bias can be questioned.
And that sample diff they provide is absolutely pointless because 1.5 versus 1.4 is guaranteed to be different because of the class version difference.

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Message was edited by:
dayrinni
Message was edited by:
dayrinni

Hi,
I have an app that is in a jar file with the .class
files (so no source code).
I'm wondering how difficult it is to attain the
source code from these .class files in my jar?
Looking through the contents of the .class files it
seems there is a large amount of readable text. For
example I see method names, variables, etc.
This leads me to believe these jars are not secure.
What is a better way?
Thanks!
Edit:
Looking around, I've noticed many java decompilers
and Sun even supports a dissembler - javap. I think
this is not cool, haha.
What way can I protect my code? To me, the value of
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so. I have yet to try it myself). I wonder if this
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All you can do is make it more difficult for people to crack things, never prevent it. True of all languages, all electronic media

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>
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How to convert a class file to exe file and how to cteate a class file to d

how to convert a class file to exe file

Hi Bhaskarq,
Hi,
It is not at all possible.
But it is a really worst method.
Please go through it.
This is a very common question asked in the comp.lang.java newsgroup. Its often useful to have an
executable application when deploying your
applications to a specific platform, but remember to
make your .class files available for users running
Unix/Macintosh/other platforms.
Microsoft provide a free system development kit (SDK),
for Java, which includes the jexegen tool. This
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with
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http://forum.java.sun.com/thread.jsp?forum=31&thread=149733
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Thanks
Bakrudeen
Technical Support Engineer
Sun MicroSystems Inc, India

Same source always makes same .class file ?

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