import java.util.Observable;

/**
 * Implements common constructor and update method dictated by
 * Observer/Observable to enable implicit invocation.
 * 
 * @author Alexander Schaap
 * 
 */

public abstract class CircularShifterAbstract implements
    CircularShifterInterface {
  private StorageInterface<StorageInterface<StorageInterface<WordInterface<?>>>> shifted;

  @Override
  public void connect(
      StorageInterface<StorageInterface<StorageInterface<WordInterface<?>>>> sls) {
    shifted = sls;
  }

  @SuppressWarnings("unchecked")
  @Override
  public void update(Observable o, Object line) {
    // casting necessary due to Observer's general types
    shifted.add(circularShifts((StorageInterface<WordInterface<?>>) line));
  }
}