Reference varibale question

[Dinesh Tahiliani]

A reference variable can refer to any object of the same type as the declared
reference, or�this is the big one�it can refer to any subtype of the
declared type!

Can anyone please explain me the meaning of above sentence in detail with example
Please......

[Deepak Bala]

if Horse extends Animal and Animal is a concrete class the following will compile

Animal a = new Animal(); //#1
Animal a = new Horse(); // #2

Animal() at #1 is of the same type and at #2 Horse() is the subtype. This is what it means.

Now please quote the source of this question.

[Krishnamoorthy Vuyala Muralidharan]

quote:
--------------------------------------------------------------------------------
A reference variable can refer to any object of the same type as the declared
reference, or�this is the big one�it can refer to any subtype of the
declared type!
--------------------------------------------------------------------------------

Can anyone please explain me the meaning of above sentence in detail with example
Please......
--------------------
Hi

A reference variable is one through which an object in the heap will be accessed.

For example:

class Animal{
public void eat(){
System.out.println("Animal's eat");
}
}
class Cat extends Animal{
}


Animal animal = new Cat();

There are three things to be noted:
1. The declaration of the reference variable 'animal'.
2. The creation of a new Cat object in the heap.
3. Assignment of the address to the animal reference variable.

If you see the above statement in the example,

[Dinesh Tahiliani]

Thanks all for your reply. I got now..

[Krishnamoorthy Vuyala Muralidharan]

quote:
--------------------------------------------------------------------------------
A reference variable can refer to any object of the same type as the declared
reference, or�this is the big one�it can refer to any subtype of the
declared type!
--------------------------------------------------------------------------------

Can anyone please explain me the meaning of above sentence in detail with example
Please......
--------------------
Hi

A reference variable is one through which an object in the heap can be accessed.

For example:

class Animal{
public void eat(){
System.out.println("Animal's eat");
}
}
class Cat extends Animal{
System.out.println("Cat's eat");
}

Animal animal = new Animal(); // correct
Animal animal = new Cat(); // correct

Animal animal = new Car(); // incorrect

There are three things to be noted:
1. The declaration of the reference variable 'animal'.
2. The creation of a new Cat object in the heap.
3. Assignment of the address to the animal reference variable.

If you see the above statement in the example,
'animal' reference variable can reference to its own type (Animal) and also reference to any of its subtype(for example, Cat object).

Hope this helps.

Kind regards
Kris