Re: sizeof in java! need help

Hi,

Thomas Weidenfeller wrote:
i have one doubt. java does not have sizeof(). so how can i know the
size of the objects in java.

You don't need it. It's that simple.

Well, the shallow size is quite simple.

But how about the "deep size" - that's nontrivial! (*)

Ciao,
Ingo

(*) It's trivial to write a reflection-based method that gets the deep size, but normally, you do not really want the deep size, but something between the flat size and the deep size (**). And that is *very* non-trivial.

(**) Mostly, you want to know the size of the object itself plus (recursively) the size of the referenced objects that are not (***) referenced by other references. :-)

(***) Except they are referenced by Objects within the same graph.

Pheww - example:


A
/ \
B C
/ | \ \
D | E \
\ | \ /
F G

Now, the "expected" sizes are (as sum of flat size):

A: A+B+C+D+E+F+G
B: B+D+E+F (and not G - or perhaps "sizeof(G)/2"?)
C: C (...)
D: D (...)
E: E (...)
F: F
G: G

Note that this is in no way 'transitive'!

Ciao,
Ingo

.

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