001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2006, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * ----------------
028 * KeyedValues.java
029 * ----------------
030 * (C) Copyright 2002-2006, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: KeyedValues.java,v 1.3.2.3 2006/11/24 10:27:33 mungady Exp $
036 *
037 * Changes:
038 * --------
039 * 23-Oct-2002 : Version 1 (DG);
040 * 12-Jan-2005 : Updated Javadocs to specify new behaviour when key
041 * is not recognised (DG);
042 * ------------- JFREECHART 1.0.0 ---------------------------------------------
043 * 02-May-2006 : Updated API docs (DG);
044 *
045 */
046
047 package org.jfree.data;
048
049 import java.util.List;
050
051 /**
052 * An ordered list of (key, value) items where the keys are unique and
053 * non-<code>null</code>.
054 *
055 * @see Values
056 * @see DefaultKeyedValues
057 */
058 public interface KeyedValues extends Values {
059
060 /**
061 * Returns the key associated with the item at a given position. Note
062 * that some implementations allow re-ordering of the data items, so the
063 * result may be transient.
064 *
065 * @param index the item index (in the range <code>0</code> to
066 * <code>getItemCount() - 1</code>).
067 *
068 * @return The key (never <code>null</code>).
069 *
070 * @throws IndexOutOfBoundsException if <code>index</code> is not in the
071 * specified range.
072 */
073 public Comparable getKey(int index);
074
075 /**
076 * Returns the index for a given key.
077 *
078 * @param key the key (<code>null</code> not permitted).
079 *
080 * @return The index, or <code>-1</code> if the key is unrecognised.
081 *
082 * @throws IllegalArgumentException if <code>key</code> is
083 * <code>null</code>.
084 */
085 public int getIndex(Comparable key);
086
087 /**
088 * Returns the keys for the values in the collection. Note that you can
089 * access the values in this collection by key or by index. For this
090 * reason, the key order is important - this method should return the keys
091 * in order. The returned list may be unmodifiable.
092 *
093 * @return The keys (never <code>null</code>).
094 */
095 public List getKeys();
096
097 /**
098 * Returns the value for a given key.
099 *
100 * @param key the key.
101 *
102 * @return The value (possibly <code>null</code>).
103 *
104 * @throws UnknownKeyException if the key is not recognised.
105 */
106 public Number getValue(Comparable key);
107
108 }