declaring an array using an interface type

[Mark Henryson]

One of the best uses of polymorphism in Java is to declare an array using an interface type, then add objects which can be from any class, as long as thay implement the interface type of the array

Is it possible for anyone to give the example codings for the above quoted thing.

[David Ulicny]

 
public interface IFace{
 public void myMethod();
}
 
public class MyClass implements IFace{
 public void myMethod(){
  //do something interesting
}
}
 
public class MyClass2 implements IFace{
 public void myMethod(){
  //do something interesting
}
}
 
 

 
....
ArrayList a = new ArrayList();
a.add(new MyClass());
a.add(new MyClass2());
 
....
for(int i = 0; i < a.size(); i++){
  ((IFace)a.get(i)).myMethod();
}
 
....
 
 

I didn't try to compile it, but the idea should be clear.

[Steve Morrow]

Is it possible for anyone to give the example codings for the above quoted thing.

Runnable[] jobs = new Runnable[5];
for (int i = 0; i < jobs.length; i++) {
    jobs[i] = JobFactory.getJob();
}

[Megs Maquito]

 public interface Pet {
 play();
}
 
public class Cat implements Pet {
}
 
public class Dog implementd Pet {
}
 
public class PetArrayList {
ArrayList<Pet> myPets = new ArrayList<Pets>;
 
Dog Bruce = new Dog();
myPets.add(Bruce);
Cat Meow = new Cat();
myPets.add(Meow);
}

not sure if this is correct though