import java.util.*;
import java.awt.*;
import java.io.*;

class SketchModel extends Observable
                  implements Serializable
{
  public boolean remove(Element element)
  {
    boolean removed = elementList.remove(element);
    if(removed)
    {
      setChanged();
      notifyObservers(element.getBounds());
    }

    return removed;
  }
  
  public void add(Element element)
  {
    elementList.add(element);
    setChanged();
    notifyObservers(element.getBounds());
  }

  public Iterator getIterator()
  {
    return elementList.listIterator();
  }

  private LinkedList elementList = new LinkedList();
}