Where inside the method is an Integer variable stored?

An Integer variable in Java is a wrapper object for the primitive type int. When you declare an Integer variable, the reference to the object is stored on the stack (if it is a local variable), and the Integer object itself is created on the heap.

For example:

Integer num = Integer.valueOf(10);

• The variable num is a reference stored on the stack (if local).
• The Integer object with the value 10 is stored on the heap.

Thus, the storage of an Integer variable occurs in two places: the reference in the stack, and the object in the heap.