Object Programming - when method when variable is shown

 
I was wondering what will be displied when whe create one type o object and inciaize with other, so the example is below:
class Mammal
{
    int it = 12;
    public void move() throws Exception
    {
      System.out.println("mammal");
    }
}
class Cat extends Mammal
{
    int it = 21;
    @Override
    public void move()
    {
         System.out.println("cat");
    }
}
public class TestMammal
{
    public static void main(String[] args) throws Exception
    {
        Mammal m = new Cat();
        Cat c = new Cat();
        c.move();        
        m.move();// exception if not 'throws Exception' in main()    
        System.out.println(m.it);
        System.out.println(c.it);    
            }
}
cat
cat
12
21

answer:
general:
variables are shown from type of object, method from instancy of object,
detailed:
but (!) at runntime jvm is looking at method declaration into type of object,
and if we declare  public void move() throws Exception
we are supposed to also : public static void main(String[] args) throws Exception
in other way we will get exception
/TestMammal.java:27: error: unreported exception Exception; must be caught or declared to be thrown
        m.move();
              ^
1 error
tested on:

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