RE: FW: Java Vs RPG on iSeries

[Fred Kulack <kulack@xxxxxxxxxx>]

On 09/20/2002 at 01:01:44 PM, java400-l-admin@midrange.com wrote:
Fred could you explain the object locking that goes on in the
implementation
code in java?

When one object is copied to another is the from object locked?  Reason
being that if thread #1 destroys the object while it is being copied by
thread #2 unpredictable results may occur.
--- end of excerpt ---

Nope. I can't really explain this, not having done no implementation nor
exploration of this part
of a JVM.

However, I would ask what you mean by "thread #1 destroys the object"?

If you mean "finalize() and garbage collect", then my expectation would be
that thread #1 is the garbage
collector and that this wouldn't happen until there are no references to
the object remaining in the application.

If there are no references remaining, then no thread can be accessing it to
copy it.
I only assume that there are 'sufficient' locking or other protocols to
ensure this but can't explain them.
Sorry.




"The stuff we call "software" is not like anything that human society
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Bruce Sterling - The Hacker Crackdown

Fred A. Kulack - IBM eServer iSeries - Enterprise Application Solutions
ERP, Java DB2 access, Jdbc, JTA, etc...
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