/* ListModel.java --
   Copyright (C) 2002, 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

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package javax.swing;

import javax.swing.event.ListDataListener;

/**
 * This is an interface to general list-like data, typically used as the
 * model object of a {@link JList} component.
 *
 * @author Graydon Hoare (graydon@redhat.com)
 */
public interface ListModel
{
  /**
   * Return the number of data elements in the list.
   *
   * @return The number of data elements in the list
   */
  int getSize();

  /**
   * Retrieves a data element at a specified index.
   *
   * @param index The index of the element to retrieve
   *
   * @return The data element at the specified index
   */
  Object getElementAt(int index);

  /**
   * Add a listener object to this model. The listener will be called
   * any time the set of elements in the model is changed.
   *
   * @param l The listener to add
   */
  void addListDataListener(ListDataListener l);

  /**
   * Add a listener object to this model. The listener will no longer be
   * called when the set of elements in the model is changed.
   *
   * @param l The listener to remove
   */
  void removeListDataListener(ListDataListener l);
}