How are variable stored?

Hi,
I'd like to know how variables are stored internally in the class file. Does Java uses an offset to refers to variable or something else? If it uses an offset it is possible to store "duplicated" variables (i.e., variables with the same name) keeping them separated, but in article of Gosling (I don't remember which) I read that Java tries to not use offsets. Can anybody explain me this?
Luca

Everything resolves down to references really !
For local variables...
A "frame" is created in the JVM, for every method being executed.
Inside that frame is basically an array of "variable slots".
The VM doesn't care about field names at this stage and just uses indexes.
It's only at compile time that field names are considered.
If you compile a class with debugging information, then then the compiler includes a "Local Variable Table". This is purely for debugging, not for the VM, and it maps field names to field positions.
If you don't include debugging information, then it's not included... the VM doesn't care.
For class field variables...
The class file format is quite strict.
No, you can't / shouldn't have duplicate class fields.
The compiler has to resolve the references down to proper indices at compile time.
regards,
Owen

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How are indexes stored

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Hi,
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Many links are there:
http://www.scribd.com/doc/2713903/Oracle-index
http://download.oracle.com/docs/cd/B28359_01/server.111/b28318/schema.htm#i5671
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http://rafioracledba.blogspot.com/

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uffdaa,
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hi
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How are variable stored?

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