001 package data;
002
003 import java.beans.PropertyChangeListener;
004
005 /**
006 * An item in a {@link Catalog}.
007 *
008 * <p>CatalogItems describe available objects by their attributes. The only attribute that is mandatory is
009 * a {@link Nameable#getName key} ({@link String}), usually a name, but it could be an ID-Number or
010 * anything. A CatalogItem can have a {@link #getValue value} attribute.<p>
011 *
012 * <p><strong>Note</strong> that the name as obtained via {@link Nameable#getName} is used as the
013 * CatalogItem's key when inserting the CatalogItem inside a Catalog.</p>
014 *
015 * <p>CatalogItems are contained in {@link Catalog Catalogs}.</p>
016 *
017 * @author Steffen Zschaler
018 * @version 2.0 18/08/1999
019 * @since v0.5
020 */
021 public interface CatalogItem extends Nameable, Comparable<Object> {
022
023 /**
024 * The programmatical name for the "value" property. This is "value".
025 */
026 public static final String VALUE_PROPERTY = "value";
027
028 /**
029 * Get the default value of this CatalogItem. Although CatalogItems have a default value, you can use any
030 * other value through the {@link CatalogItemValue} adapter.
031 *
032 * @override Always
033 */
034 public Value getValue();
035
036 /**
037 * Get the Catalog that currently contains this CatalogItem.
038 *
039 * @override Always
040 */
041 public Catalog getCatalog();
042
043 /**
044 * Add a PropertyChangeListener that will receive events whenever the "value" property changes.
045 *
046 * @override Always
047 */
048 public void addValueListener(PropertyChangeListener pcl);
049
050 /**
051 * Remove a PropertyChangeListener for the "value" property.
052 *
053 * @override Always
054 */
055 public void removeValueListener(PropertyChangeListener pcl);
056 }