Java Object Method Stack Frame Parameters

So in java, say you have a non-static method ‘bar()’ in an class ‘Foo’.

class Foo
{
    private int m_answer;

    public Foo()
    {
        m_answer = -1;
    }

    public void bar(int newAnswer)
    {
        m_answer = newAnswer;
    }
}

JavaScript
​x
 
class Foo{    private int m_answer;​    public Foo()    {        m_answer = -1;    }​    public void bar(int newAnswer)    {        m_answer = newAnswer;    }}​

Say then that you call this method like so:

Foo myFoo = new Foo();
myFoo.bar(42);

JavaScript
 
Foo myFoo = new Foo();myFoo.bar(42);​

Now the stack frame for the call includes the integer parameter, as well as a ‘this’ parameter to be used as an internal reference to the object.

What other interesting parameters are copied to the new stack frame, in addition to ‘this’ and the method parameters?

Answer

Usually a pointer to the calling instruction, so that the VM (in this case, the CPU in native apps) will know where to set the instruction pointer (or PC – Program Counter) so the stack will be unfolded correctly

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Answer