Integer and Integer Array storage on stack/heap

Question

I'm curious to know how Integer and Integer Array are stored on the stack/heap in java, is there a link someone could point me to? Or could someone explain it to me please.

Update 1: and how does this affect the way an integer and an integer array are passed as arguments to methods in Java.

Thank You

Answer 1

Whenever you declare a variable within a local scope(a method) it gets put on the stack.

That is: Type myVariable will push space for a new variable onto that methods stack frame, but it's not usable yet as it's uninitialized.

When you assign a value to the variable, that value is put into the reserved space on the stack.

Now here's the tricky part. If the type is primitive, the value contains the value you assigned. For example, int a = 55 will literally put the value 55 into that space.
However, if the type is non primitive, that is some subclass of Object, then the value put onto the stack is actually a memory address. This memory address points to a place on the heap, which is where the actual Object is stored.

The object is put into the heap on creation.

An Example

private void myMethod()
{
    Object myObject = new Object();
}

We're declaring a variable, so we get space on the stack frame. The type is an Object, so this value is going to be a pointer to the space on the heap that was allocated when the Object was created.