import java.util.Observer;


/**
 * Stores lines. Secret: storage format.
 * 
 * @author Alexander Schaap
 * 
 * @param <T>
 *          Type of the lines being stored
 */
public interface StorageInterface<T> {
  /**
   * adds line at the end of the storage
   * 
   * @param line
   */
  public void add(T line);

  /**
   * returns contents of line at given index
   * 
   * @param index
   * @return line of type T
   */
  public T get(int index);

  /**
   * replaces line at index with given line
   * 
   * @param index
   * @param line
   */
  public void set(int index, T line);

  /**
   * returns size of the storage
   * 
   * @return int
   */
  public int length();

  /**
   * Resets the storage, primarily for reuse during testing
   */
  public void reset();

  /**
   * sets sorting algorithm to be provided to Alphabetizer
   * 
   * @param algorithm
   *          - an implementation of SortInterface<?>
   */
  // public void setSortingAlgorithm(AlphabetizerInterface<?> algorithm);
  public void connect(Observer o);
}