Where do class level reference variable get stored

[Nikita Dutt]

Hi All,

Have a small question where do reference variable at the class level gets stored ; for example

 

class MyClass {
public MyClass () {
  System.out.println("Inside Constructor");
}
}


public Class Demo {

MyClass cL = new MyClass(); 
// Where will reference variable cL get stored  ? heap or stack 

public void myMethod()
{
           MyClass C2 = new MyClass(); 
        // C2 will be on stack referring the actual object which will be on heap // ( My Understanding ) Right ?
}

}

Hope i make sense ; thanks in advance

Regards

[Campbell Ritchie]

Search for the BCEL handbook, which explains it better than I would, though it may be out of date.
You haven't got any class variables in that code, only instance variables.
The instance variable is stored in the heap as part of the object, and it points to another object on the heap (at least I think it does). In Java6 that becomes slightly inaccurate.

[Abhijeet Sutar]

Nikita Dutt wrote:Hi All,

Have a small question where do reference variable at the class level gets stored ; for example

 

class MyClass {
public MyClass () {
  System.out.println("Inside Constructor");
}
}


public class Demo {

MyClass cL = new MyClass(); 
// Where will reference variable cL get stored  ? heap or stack 

public void myMethod()
{
           MyClass C2 = new MyClass(); 
        // C2 will be on stack referring the actual object which will be on heap // ( My Understanding ) Right ?
}

}

Hope i make sense ; thanks in advance

Regards

At line 12, you are creating the instance variable/field , Which is the reference variable, declaration and initialization ,of class MyClass
When you will create the instance of the

class Demo

,then that instance will be stored on Heap memory along with all its instance variables/fields i.e. the state of the object

So, reference variable cL will be on heap as along as instance is on heap
and yes reference variable c2 which is declared inside method will be live as long as method code executes.

Hope this helps..

[Rob Spoor]

Please SearchFirst. This question has been asked and answered a few times before.

[Nikita Dutt]

Sorry Rob for the inconvenience ; thanks to all of you ; esp my fellow greenhorn ; to add to it am i right when i say that the reference variable inside the method will be stored on the stack and the actual object it points to is on heap

[Campbell Ritchie]

You didn't ask about local variables. You are nearly right.
There are a few short-lived objects which are created on the stack in Java6. I can't remember any more details.

[Nikita Dutt]

Hi All,

Just to sum up things

Reference variable cL will be stored on heap and will refer to an object of MyClass which will again be on Heap.

Reference variable C2 will be stored on stack and will refer to an object of MyClass which will be on Heap.



Hope i make sense


Regards