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how primitives and objects are laid in memory?

Dez Max
Ranch Hand

Joined: Oct 01, 2002
Posts: 41
Hi Folks,
I want to know how java objects and primitives objects are laid out in memory. How static variables and objects are stored. For ex
int a = 12;
how memory allocation happens for variable a.
Thanks in advance.
David O'Meara

Joined: Mar 06, 2001
Posts: 13459

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Cindy Glass
"The Hood"

Joined: Sep 29, 2000
Posts: 8521
Objects are stored on the heap. Static variables are stored with the Classfile. Variable references are stored in the stack related to the Frame. There is a frame for each method invoked. So local variables find themselves on the stack for the method that they are local to.
The example that you gave shows the integer as a constant value. That value would be stored in the Constant Pool, with all the other constants and literals and Strings.
You may enjoy reading the Java Virtual Machine Specifications for details on how such things work. .

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