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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package javax.swing;

/**
 * A data model for a combo box. This interface extends <code>ListDataModel</code>
 * and adds the concept of a <i>selected item</i>. The selected item is generally
 * the item which is visible in the combo box display area.
 * <p>
 * The selected item may not necessarily be managed by the underlying
 * <code>ListModel</code>. This disjoint behavior allows for the temporary
 * storage and retrieval of a selected item in the model.
 *
 * @param <E> the type of the elements of this model
 *
 * @author Arnaud Weber
 * @since 1.2
 */
public interface ComboBoxModel<E> extends ListModel<E> {

  /**
   * Set the selected item. The implementation of this  method should notify
   * all registered <code>ListDataListener</code>s that the contents
   * have changed.
   *
   * @param anItem the list object to select or <code>null</code>
   *        to clear the selection
   */
  void setSelectedItem(Object anItem);

  /**
   * Returns the selected item
   * @return The selected item or <code>null</code> if there is no selection
   */
  Object getSelectedItem();
}
