class MySpecialObject {
    // Space for this variable is allocated on the heap.
    int a;
}
// In fact, space for the whole object instance is allocated on the heap.


public class VariableExamples {

    // Static variable allocated in global area.
    static int b = 1;


    //                       NOTE: parameter variable argv

    public static void main (String[] argv)
    {
        // Local variable 'c' allocated on the stack.
        int c = 2;

        // The value in 'c' gets copied into the parameter variable (see below).
        print (c);

        // Space for the whole object is allocated on the heap.
        MySpecialObject obj = new MySpecialObject ();

        // Access variables inside the object via variable name and '.' operator.
        obj.a = 3;
        print (obj.a);

        // When the method exits, 'c' and 'obj' both disappear.
    }
    

    //                 Parameter variable x is on the stack.
    static void print (int x)
    {
        System.out.println ("x=" + x);

        // You can treat the parameter like any variable.
        x = 4;

        // Static variable 'b' is accessible here.
        System.out.println ("b=" + b);

        // When the method exits, 'x' disappears.
    }
    
}