OnJava8-Examples/collections/NonCollectionSequence.java

// collections/NonCollectionSequence.java
// (c)2021 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
import typeinfo.pets.*;
import java.util.*;

class PetSequence {
  protected Pet[] pets = new PetCreator().array(8);
}

public class NonCollectionSequence extends PetSequence {
  public Iterator<Pet> iterator() {
    return new Iterator<Pet>() {
      private int index = 0;
      @Override public boolean hasNext() {
        return index < pets.length;
      }
      @Override
      public Pet next() { return pets[index++]; }
      @Override
      public void remove() { // Not implemented
        throw new UnsupportedOperationException();
      }
    };
  }
  public static void main(String[] args) {
    NonCollectionSequence nc =
      new NonCollectionSequence();
    InterfaceVsIterator.display(nc.iterator());
  }
}
/* Output:
0:Rat 1:Manx 2:Cymric 3:Mutt 4:Pug 5:Cymric 6:Pug
7:Manx
*/