001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2011, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * -------------
028 * XYSeries.java
029 * -------------
030 * (C) Copyright 2001-2011, Object Refinery Limited and Contributors.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   Aaron Metzger;
034 *                   Jonathan Gabbai;
035 *                   Richard Atkinson;
036 *                   Michel Santos;
037 *                   Ted Schwartz (fix for bug 1955483);
038 *
039 * Changes
040 * -------
041 * 15-Nov-2001 : Version 1 (DG);
042 * 03-Apr-2002 : Added an add(double, double) method (DG);
043 * 29-Apr-2002 : Added a clear() method (ARM);
044 * 06-Jun-2002 : Updated Javadoc comments (DG);
045 * 29-Aug-2002 : Modified to give user control over whether or not duplicate
046 *               x-values are allowed (DG);
047 * 07-Oct-2002 : Fixed errors reported by Checkstyle (DG);
048 * 11-Nov-2002 : Added maximum item count, code contributed by Jonathan
049 *               Gabbai (DG);
050 * 26-Mar-2003 : Implemented Serializable (DG);
051 * 04-Aug-2003 : Added getItems() method (DG);
052 * 15-Aug-2003 : Changed 'data' from private to protected, added new add()
053 *               methods with a 'notify' argument (DG);
054 * 22-Sep-2003 : Added getAllowDuplicateXValues() method (RA);
055 * 29-Jan-2004 : Added autoSort attribute, based on a contribution by
056 *               Michel Santos - see patch 886740 (DG);
057 * 03-Feb-2004 : Added indexOf() method (DG);
058 * 16-Feb-2004 : Added remove() method (DG);
059 * 18-Aug-2004 : Moved from org.jfree.data --> org.jfree.data.xy (DG);
060 * 21-Feb-2005 : Added update(Number, Number) and addOrUpdate(Number, Number)
061 *               methods (DG);
062 * 03-May-2005 : Added a new constructor, fixed the setMaximumItemCount()
063 *               method to remove items (and notify listeners) if necessary,
064 *               fixed the add() and addOrUpdate() methods to handle unsorted
065 *               series (DG);
066 * ------------- JFreeChart 1.0.x ---------------------------------------------
067 * 11-Jan-2005 : Renamed update(int, Number) --> updateByIndex() (DG);
068 * 15-Jan-2007 : Added toArray() method (DG);
069 * 31-Oct-2007 : Implemented faster hashCode() (DG);
070 * 22-Nov-2007 : Reimplemented clone() (DG);
071 * 01-May-2008 : Fixed bug 1955483 in addOrUpdate() method, thanks to
072 *               Ted Schwartz (DG);
073 * 24-Nov-2008 : Further fix for 1955483 (DG);
074 * 06-Mar-2009 : Added minX, maxX, minY and maxY fields (DG);
075 * 10-Jun-2009 : Make clones to isolate XYDataItem instances used
076 *               for data storage (DG);
077 * 
078 */
079
080package org.jfree.data.xy;
081
082import java.io.Serializable;
083import java.util.Collections;
084import java.util.Iterator;
085import java.util.List;
086
087import org.jfree.data.general.Series;
088import org.jfree.data.general.SeriesChangeEvent;
089import org.jfree.data.general.SeriesException;
090import org.jfree.util.ObjectUtilities;
091
092/**
093 * Represents a sequence of zero or more data items in the form (x, y).  By
094 * default, items in the series will be sorted into ascending order by x-value,
095 * and duplicate x-values are permitted.  Both the sorting and duplicate
096 * defaults can be changed in the constructor.  Y-values can be
097 * <code>null</code> to represent missing values.
098 */
099public class XYSeries extends Series implements Cloneable, Serializable {
100
101    /** For serialization. */
102    static final long serialVersionUID = -5908509288197150436L;
103
104    // In version 0.9.12, in response to several developer requests, I changed
105    // the 'data' attribute from 'private' to 'protected', so that others can
106    // make subclasses that work directly with the underlying data structure.
107
108    /** Storage for the data items in the series. */
109    protected List data;
110
111    /** The maximum number of items for the series. */
112    private int maximumItemCount = Integer.MAX_VALUE;
113
114    /**
115     * A flag that controls whether the items are automatically sorted
116     * (by x-value ascending).
117     */
118    private boolean autoSort;
119
120    /** A flag that controls whether or not duplicate x-values are allowed. */
121    private boolean allowDuplicateXValues;
122
123    /** The lowest x-value in the series, excluding Double.NaN values. */
124    private double minX;
125
126    /** The highest x-value in the series, excluding Double.NaN values. */
127    private double maxX;
128
129    /** The lowest y-value in the series, excluding Double.NaN values. */
130    private double minY;
131
132    /** The highest y-value in the series, excluding Double.NaN values. */
133    private double maxY;
134
135    /**
136     * Creates a new empty series.  By default, items added to the series will
137     * be sorted into ascending order by x-value, and duplicate x-values will
138     * be allowed (these defaults can be modified with another constructor.
139     *
140     * @param key  the series key (<code>null</code> not permitted).
141     */
142    public XYSeries(Comparable key) {
143        this(key, true, true);
144    }
145
146    /**
147     * Constructs a new empty series, with the auto-sort flag set as requested,
148     * and duplicate values allowed.
149     *
150     * @param key  the series key (<code>null</code> not permitted).
151     * @param autoSort  a flag that controls whether or not the items in the
152     *                  series are sorted.
153     */
154    public XYSeries(Comparable key, boolean autoSort) {
155        this(key, autoSort, true);
156    }
157
158    /**
159     * Constructs a new xy-series that contains no data.  You can specify
160     * whether or not duplicate x-values are allowed for the series.
161     *
162     * @param key  the series key (<code>null</code> not permitted).
163     * @param autoSort  a flag that controls whether or not the items in the
164     *                  series are sorted.
165     * @param allowDuplicateXValues  a flag that controls whether duplicate
166     *                               x-values are allowed.
167     */
168    public XYSeries(Comparable key, boolean autoSort,
169            boolean allowDuplicateXValues) {
170        super(key);
171        this.data = new java.util.ArrayList();
172        this.autoSort = autoSort;
173        this.allowDuplicateXValues = allowDuplicateXValues;
174        this.minX = Double.NaN;
175        this.maxX = Double.NaN;
176        this.minY = Double.NaN;
177        this.maxY = Double.NaN;
178    }
179
180    /**
181     * Returns the smallest x-value in the series, ignoring any Double.NaN
182     * values.  This method returns Double.NaN if there is no smallest x-value
183     * (for example, when the series is empty).
184     *
185     * @return The smallest x-value.
186     *
187     * @see #getMaxX()
188     *
189     * @since 1.0.13
190     */
191    public double getMinX() {
192        return this.minX;
193    }
194
195    /**
196     * Returns the largest x-value in the series, ignoring any Double.NaN
197     * values.  This method returns Double.NaN if there is no largest x-value
198     * (for example, when the series is empty).
199     *
200     * @return The largest x-value.
201     *
202     * @see #getMinX()
203     *
204     * @since 1.0.13
205     */
206    public double getMaxX() {
207        return this.maxX;
208    }
209
210    /**
211     * Returns the smallest y-value in the series, ignoring any null and
212     * Double.NaN values.  This method returns Double.NaN if there is no
213     * smallest y-value (for example, when the series is empty).
214     *
215     * @return The smallest y-value.
216     *
217     * @see #getMaxY()
218     *
219     * @since 1.0.13
220     */
221    public double getMinY() {
222        return this.minY;
223    }
224
225    /**
226     * Returns the largest y-value in the series, ignoring any Double.NaN
227     * values.  This method returns Double.NaN if there is no largest y-value
228     * (for example, when the series is empty).
229     *
230     * @return The largest y-value.
231     *
232     * @see #getMinY()
233     *
234     * @since 1.0.13
235     */
236    public double getMaxY() {
237        return this.maxY;
238    }
239
240    /**
241     * Updates the cached values for the minimum and maximum data values.
242     *
243     * @param item  the item added (<code>null</code> not permitted).
244     *
245     * @since 1.0.13
246     */
247    private void updateBoundsForAddedItem(XYDataItem item) {
248        double x = item.getXValue();
249        this.minX = minIgnoreNaN(this.minX, x);
250        this.maxX = maxIgnoreNaN(this.maxX, x);
251        if (item.getY() != null) {
252            double y = item.getYValue();
253            this.minY = minIgnoreNaN(this.minY, y);
254            this.maxY = maxIgnoreNaN(this.maxY, y);
255        }
256    }
257
258    /**
259     * Updates the cached values for the minimum and maximum data values on
260     * the basis that the specified item has just been removed.
261     *
262     * @param item  the item added (<code>null</code> not permitted).
263     *
264     * @since 1.0.13
265     */
266    private void updateBoundsForRemovedItem(XYDataItem item) {
267        boolean itemContributesToXBounds = false;
268        boolean itemContributesToYBounds = false;
269        double x = item.getXValue();
270        if (!Double.isNaN(x)) {
271            if (x <= this.minX || x >= this.maxX) {
272                itemContributesToXBounds = true;
273            }
274        }
275        if (item.getY() != null) {
276            double y = item.getYValue();
277            if (!Double.isNaN(y)) {
278                if (y <= this.minY || y >= this.maxY) {
279                    itemContributesToYBounds = true;
280                }
281            }
282        }
283        if (itemContributesToYBounds) {
284            findBoundsByIteration();
285        }
286        else if (itemContributesToXBounds) {
287            if (getAutoSort()) {
288                this.minX = getX(0).doubleValue();
289                this.maxX = getX(getItemCount() - 1).doubleValue();
290            }
291            else {
292                findBoundsByIteration();
293            }
294        }
295    }
296
297    /**
298     * Finds the bounds of the x and y values for the series, by iterating
299     * through all the data items.
300     *
301     * @since 1.0.13
302     */
303    private void findBoundsByIteration() {
304        this.minX = Double.NaN;
305        this.maxX = Double.NaN;
306        this.minY = Double.NaN;
307        this.maxY = Double.NaN;
308        Iterator iterator = this.data.iterator();
309        while (iterator.hasNext()) {
310            XYDataItem item = (XYDataItem) iterator.next();
311            updateBoundsForAddedItem(item);
312        }
313    }
314
315    /**
316     * Returns the flag that controls whether the items in the series are
317     * automatically sorted.  There is no setter for this flag, it must be
318     * defined in the series constructor.
319     *
320     * @return A boolean.
321     */
322    public boolean getAutoSort() {
323        return this.autoSort;
324    }
325
326    /**
327     * Returns a flag that controls whether duplicate x-values are allowed.
328     * This flag can only be set in the constructor.
329     *
330     * @return A boolean.
331     */
332    public boolean getAllowDuplicateXValues() {
333        return this.allowDuplicateXValues;
334    }
335
336    /**
337     * Returns the number of items in the series.
338     *
339     * @return The item count.
340     *
341     * @see #getItems()
342     */
343    public int getItemCount() {
344        return this.data.size();
345    }
346
347    /**
348     * Returns the list of data items for the series (the list contains
349     * {@link XYDataItem} objects and is unmodifiable).
350     *
351     * @return The list of data items.
352     */
353    public List getItems() {
354        return Collections.unmodifiableList(this.data);
355    }
356
357    /**
358     * Returns the maximum number of items that will be retained in the series.
359     * The default value is <code>Integer.MAX_VALUE</code>.
360     *
361     * @return The maximum item count.
362     *
363     * @see #setMaximumItemCount(int)
364     */
365    public int getMaximumItemCount() {
366        return this.maximumItemCount;
367    }
368
369    /**
370     * Sets the maximum number of items that will be retained in the series.
371     * If you add a new item to the series such that the number of items will
372     * exceed the maximum item count, then the first element in the series is
373     * automatically removed, ensuring that the maximum item count is not
374     * exceeded.
375     * <p>
376     * Typically this value is set before the series is populated with data,
377     * but if it is applied later, it may cause some items to be removed from
378     * the series (in which case a {@link SeriesChangeEvent} will be sent to
379     * all registered listeners).
380     *
381     * @param maximum  the maximum number of items for the series.
382     */
383    public void setMaximumItemCount(int maximum) {
384        this.maximumItemCount = maximum;
385        int remove = this.data.size() - maximum;
386        if (remove > 0) {
387            this.data.subList(0, remove).clear();
388            findBoundsByIteration();
389            fireSeriesChanged();
390        }
391    }
392
393    /**
394     * Adds a data item to the series and sends a {@link SeriesChangeEvent} to
395     * all registered listeners.
396     *
397     * @param item  the (x, y) item (<code>null</code> not permitted).
398     */
399    public void add(XYDataItem item) {
400        // argument checking delegated...
401        add(item, true);
402    }
403
404    /**
405     * Adds a data item to the series and sends a {@link SeriesChangeEvent} to
406     * all registered listeners.
407     *
408     * @param x  the x value.
409     * @param y  the y value.
410     */
411    public void add(double x, double y) {
412        add(new Double(x), new Double(y), true);
413    }
414
415    /**
416     * Adds a data item to the series and, if requested, sends a
417     * {@link SeriesChangeEvent} to all registered listeners.
418     *
419     * @param x  the x value.
420     * @param y  the y value.
421     * @param notify  a flag that controls whether or not a
422     *                {@link SeriesChangeEvent} is sent to all registered
423     *                listeners.
424     */
425    public void add(double x, double y, boolean notify) {
426        add(new Double(x), new Double(y), notify);
427    }
428
429    /**
430     * Adds a data item to the series and sends a {@link SeriesChangeEvent} to
431     * all registered listeners.  The unusual pairing of parameter types is to
432     * make it easier to add <code>null</code> y-values.
433     *
434     * @param x  the x value.
435     * @param y  the y value (<code>null</code> permitted).
436     */
437    public void add(double x, Number y) {
438        add(new Double(x), y);
439    }
440
441    /**
442     * Adds a data item to the series and, if requested, sends a
443     * {@link SeriesChangeEvent} to all registered listeners.  The unusual
444     * pairing of parameter types is to make it easier to add null y-values.
445     *
446     * @param x  the x value.
447     * @param y  the y value (<code>null</code> permitted).
448     * @param notify  a flag that controls whether or not a
449     *                {@link SeriesChangeEvent} is sent to all registered
450     *                listeners.
451     */
452    public void add(double x, Number y, boolean notify) {
453        add(new Double(x), y, notify);
454    }
455
456    /**
457     * Adds a new data item to the series (in the correct position if the
458     * <code>autoSort</code> flag is set for the series) and sends a
459     * {@link SeriesChangeEvent} to all registered listeners.
460     * <P>
461     * Throws an exception if the x-value is a duplicate AND the
462     * allowDuplicateXValues flag is false.
463     *
464     * @param x  the x-value (<code>null</code> not permitted).
465     * @param y  the y-value (<code>null</code> permitted).
466     *
467     * @throws SeriesException if the x-value is a duplicate and the
468     *     <code>allowDuplicateXValues</code> flag is not set for this series.
469     */
470    public void add(Number x, Number y) {
471        // argument checking delegated...
472        add(x, y, true);
473    }
474
475    /**
476     * Adds new data to the series and, if requested, sends a
477     * {@link SeriesChangeEvent} to all registered listeners.
478     * <P>
479     * Throws an exception if the x-value is a duplicate AND the
480     * allowDuplicateXValues flag is false.
481     *
482     * @param x  the x-value (<code>null</code> not permitted).
483     * @param y  the y-value (<code>null</code> permitted).
484     * @param notify  a flag the controls whether or not a
485     *                {@link SeriesChangeEvent} is sent to all registered
486     *                listeners.
487     */
488    public void add(Number x, Number y, boolean notify) {
489        // delegate argument checking to XYDataItem...
490        XYDataItem item = new XYDataItem(x, y);
491        add(item, notify);
492    }
493
494    /**
495     * Adds a data item to the series and, if requested, sends a
496     * {@link SeriesChangeEvent} to all registered listeners.
497     *
498     * @param item  the (x, y) item (<code>null</code> not permitted).
499     * @param notify  a flag that controls whether or not a
500     *                {@link SeriesChangeEvent} is sent to all registered
501     *                listeners.
502     */
503    public void add(XYDataItem item, boolean notify) {
504        if (item == null) {
505            throw new IllegalArgumentException("Null 'item' argument.");
506        }
507        item = (XYDataItem) item.clone();
508        if (this.autoSort) {
509            int index = Collections.binarySearch(this.data, item);
510            if (index < 0) {
511                this.data.add(-index - 1, item);
512            }
513            else {
514                if (this.allowDuplicateXValues) {
515                    // need to make sure we are adding *after* any duplicates
516                    int size = this.data.size();
517                    while (index < size && item.compareTo(
518                            this.data.get(index)) == 0) {
519                        index++;
520                    }
521                    if (index < this.data.size()) {
522                        this.data.add(index, item);
523                    }
524                    else {
525                        this.data.add(item);
526                    }
527                }
528                else {
529                    throw new SeriesException("X-value already exists.");
530                }
531            }
532        }
533        else {
534            if (!this.allowDuplicateXValues) {
535                // can't allow duplicate values, so we need to check whether
536                // there is an item with the given x-value already
537                int index = indexOf(item.getX());
538                if (index >= 0) {
539                    throw new SeriesException("X-value already exists.");
540                }
541            }
542            this.data.add(item);
543        }
544        updateBoundsForAddedItem(item);
545        if (getItemCount() > this.maximumItemCount) {
546            XYDataItem removed = (XYDataItem) this.data.remove(0);
547            updateBoundsForRemovedItem(removed);
548        }
549        if (notify) {
550            fireSeriesChanged();
551        }
552    }
553
554    /**
555     * Deletes a range of items from the series and sends a
556     * {@link SeriesChangeEvent} to all registered listeners.
557     *
558     * @param start  the start index (zero-based).
559     * @param end  the end index (zero-based).
560     */
561    public void delete(int start, int end) {
562        this.data.subList(start, end + 1).clear();
563        findBoundsByIteration();
564        fireSeriesChanged();
565    }
566
567    /**
568     * Removes the item at the specified index and sends a
569     * {@link SeriesChangeEvent} to all registered listeners.
570     *
571     * @param index  the index.
572     *
573     * @return The item removed.
574     */
575    public XYDataItem remove(int index) {
576        XYDataItem removed = (XYDataItem) this.data.remove(index);
577        updateBoundsForRemovedItem(removed);
578        fireSeriesChanged();
579        return removed;
580    }
581
582    /**
583     * Removes an item with the specified x-value and sends a
584     * {@link SeriesChangeEvent} to all registered listeners.  Note that when
585     * a series permits multiple items with the same x-value, this method
586     * could remove any one of the items with that x-value.
587     *
588     * @param x  the x-value.
589
590     * @return The item removed.
591     */
592    public XYDataItem remove(Number x) {
593        return remove(indexOf(x));
594    }
595
596    /**
597     * Removes all data items from the series and sends a
598     * {@link SeriesChangeEvent} to all registered listeners.
599     */
600    public void clear() {
601        if (this.data.size() > 0) {
602            this.data.clear();
603            this.minX = Double.NaN;
604            this.maxX = Double.NaN;
605            this.minY = Double.NaN;
606            this.maxY = Double.NaN;
607            fireSeriesChanged();
608        }
609    }
610
611    /**
612     * Return the data item with the specified index.
613     *
614     * @param index  the index.
615     *
616     * @return The data item with the specified index.
617     */
618    public XYDataItem getDataItem(int index) {
619        XYDataItem item = (XYDataItem) this.data.get(index);
620        return (XYDataItem) item.clone();
621    }
622
623    /**
624     * Return the data item with the specified index.
625     *
626     * @param index  the index.
627     *
628     * @return The data item with the specified index.
629     *
630     * @since 1.0.14
631     */
632    XYDataItem getRawDataItem(int index) {
633        return (XYDataItem) this.data.get(index);
634    }
635
636    /**
637     * Returns the x-value at the specified index.
638     *
639     * @param index  the index (zero-based).
640     *
641     * @return The x-value (never <code>null</code>).
642     */
643    public Number getX(int index) {
644        return getRawDataItem(index).getX();
645    }
646
647    /**
648     * Returns the y-value at the specified index.
649     *
650     * @param index  the index (zero-based).
651     *
652     * @return The y-value (possibly <code>null</code>).
653     */
654    public Number getY(int index) {
655        return getRawDataItem(index).getY();
656    }
657
658    /**
659     * Updates the value of an item in the series and sends a
660     * {@link SeriesChangeEvent} to all registered listeners.
661     *
662     * @param index  the item (zero based index).
663     * @param y  the new value (<code>null</code> permitted).
664     *
665     * @deprecated Renamed {@link #updateByIndex(int, Number)} to avoid
666     *         confusion with the {@link #update(Number, Number)} method.
667     */
668    public void update(int index, Number y) {
669        XYDataItem item = getRawDataItem(index);
670
671        // figure out if we need to iterate through all the y-values
672        boolean iterate = false;
673        double oldY = item.getYValue();
674        if (!Double.isNaN(oldY)) {
675            iterate = oldY <= this.minY || oldY >= this.maxY;
676        }
677        item.setY(y);
678
679        if (iterate) {
680            findBoundsByIteration();
681        }
682        else if (y != null) {
683            double yy = y.doubleValue();
684            this.minY = minIgnoreNaN(this.minY, yy);
685            this.maxY = maxIgnoreNaN(this.maxY, yy);
686        }
687        fireSeriesChanged();
688    }
689
690    /**
691     * A function to find the minimum of two values, but ignoring any
692     * Double.NaN values.
693     *
694     * @param a  the first value.
695     * @param b  the second value.
696     *
697     * @return The minimum of the two values.
698     */
699    private double minIgnoreNaN(double a, double b) {
700        if (Double.isNaN(a)) {
701            return b;
702        }
703        if (Double.isNaN(b)) {
704            return a;
705        }
706        return Math.min(a, b);
707    }
708
709    /**
710     * A function to find the maximum of two values, but ignoring any
711     * Double.NaN values.
712     *
713     * @param a  the first value.
714     * @param b  the second value.
715     *
716     * @return The maximum of the two values.
717     */
718    private double maxIgnoreNaN(double a, double b) {
719        if (Double.isNaN(a)) {
720            return b;
721        }
722        if (Double.isNaN(b)) {
723            return a;
724        }
725        return Math.max(a, b);
726    }
727
728    /**
729     * Updates the value of an item in the series and sends a
730     * {@link SeriesChangeEvent} to all registered listeners.
731     *
732     * @param index  the item (zero based index).
733     * @param y  the new value (<code>null</code> permitted).
734     *
735     * @since 1.0.1
736     */
737    public void updateByIndex(int index, Number y) {
738        update(index, y);
739    }
740
741    /**
742     * Updates an item in the series.
743     *
744     * @param x  the x-value (<code>null</code> not permitted).
745     * @param y  the y-value (<code>null</code> permitted).
746     *
747     * @throws SeriesException if there is no existing item with the specified
748     *         x-value.
749     */
750    public void update(Number x, Number y) {
751        int index = indexOf(x);
752        if (index < 0) {
753            throw new SeriesException("No observation for x = " + x);
754        }
755        updateByIndex(index, y);
756    }
757
758    /**
759     * Adds or updates an item in the series and sends a
760     * {@link SeriesChangeEvent} to all registered listeners.
761     *
762     * @param x  the x-value.
763     * @param y  the y-value.
764     *
765     * @return The item that was overwritten, if any.
766     *
767     * @since 1.0.10
768     */
769    public XYDataItem addOrUpdate(double x, double y) {
770        return addOrUpdate(new Double(x), new Double(y));
771    }
772
773    /**
774     * Adds or updates an item in the series and sends a
775     * {@link SeriesChangeEvent} to all registered listeners.
776     *
777     * @param x  the x-value (<code>null</code> not permitted).
778     * @param y  the y-value (<code>null</code> permitted).
779     *
780     * @return A copy of the overwritten data item, or <code>null</code> if no
781     *         item was overwritten.
782     */
783    public XYDataItem addOrUpdate(Number x, Number y) {
784        // defer argument checking
785        return addOrUpdate(new XYDataItem(x, y));
786    }
787
788    /**
789     * Adds or updates an item in the series and sends a
790     * {@link SeriesChangeEvent} to all registered listeners.
791     *
792     * @param item  the data item (<code>null</code> not permitted).
793     *
794     * @return A copy of the overwritten data item, or <code>null</code> if no
795     *         item was overwritten.
796     *
797     * @since 1.0.14
798     */
799    public XYDataItem addOrUpdate(XYDataItem item) {
800        if (item == null) {
801            throw new IllegalArgumentException("Null 'item' argument.");
802        }
803        if (this.allowDuplicateXValues) {
804            add(item);
805            return null;
806        }
807
808        // if we get to here, we know that duplicate X values are not permitted
809        XYDataItem overwritten = null;
810        int index = indexOf(item.getX());
811        if (index >= 0) {
812            XYDataItem existing = (XYDataItem) this.data.get(index);
813            overwritten = (XYDataItem) existing.clone();
814            // figure out if we need to iterate through all the y-values
815            boolean iterate = false;
816            double oldY = existing.getYValue();
817            if (!Double.isNaN(oldY)) {
818                iterate = oldY <= this.minY || oldY >= this.maxY;
819            }
820            existing.setY(item.getY());
821
822            if (iterate) {
823                findBoundsByIteration();
824            }
825            else if (item.getY() != null) {
826                double yy = item.getY().doubleValue();
827                this.minY = minIgnoreNaN(this.minY, yy);
828                this.maxY = minIgnoreNaN(this.maxY, yy);
829            }
830        }
831        else {
832            // if the series is sorted, the negative index is a result from
833            // Collections.binarySearch() and tells us where to insert the
834            // new item...otherwise it will be just -1 and we should just
835            // append the value to the list...
836            item = (XYDataItem) item.clone();
837            if (this.autoSort) {
838                this.data.add(-index - 1, item);
839            }
840            else {
841                this.data.add(item);
842            }
843            updateBoundsForAddedItem(item);
844
845            // check if this addition will exceed the maximum item count...
846            if (getItemCount() > this.maximumItemCount) {
847                XYDataItem removed = (XYDataItem) this.data.remove(0);
848                updateBoundsForRemovedItem(removed);
849            }
850        }
851        fireSeriesChanged();
852        return overwritten;
853    }
854
855    /**
856     * Returns the index of the item with the specified x-value, or a negative
857     * index if the series does not contain an item with that x-value.  Be
858     * aware that for an unsorted series, the index is found by iterating
859     * through all items in the series.
860     *
861     * @param x  the x-value (<code>null</code> not permitted).
862     *
863     * @return The index.
864     */
865    public int indexOf(Number x) {
866        if (this.autoSort) {
867            return Collections.binarySearch(this.data, new XYDataItem(x, null));
868        }
869        else {
870            for (int i = 0; i < this.data.size(); i++) {
871                XYDataItem item = (XYDataItem) this.data.get(i);
872                if (item.getX().equals(x)) {
873                    return i;
874                }
875            }
876            return -1;
877        }
878    }
879
880    /**
881     * Returns a new array containing the x and y values from this series.
882     *
883     * @return A new array containing the x and y values from this series.
884     *
885     * @since 1.0.4
886     */
887    public double[][] toArray() {
888        int itemCount = getItemCount();
889        double[][] result = new double[2][itemCount];
890        for (int i = 0; i < itemCount; i++) {
891            result[0][i] = this.getX(i).doubleValue();
892            Number y = getY(i);
893            if (y != null) {
894                result[1][i] = y.doubleValue();
895            }
896            else {
897                result[1][i] = Double.NaN;
898            }
899        }
900        return result;
901    }
902
903    /**
904     * Returns a clone of the series.
905     *
906     * @return A clone of the series.
907     *
908     * @throws CloneNotSupportedException if there is a cloning problem.
909     */
910    public Object clone() throws CloneNotSupportedException {
911        XYSeries clone = (XYSeries) super.clone();
912        clone.data = (List) ObjectUtilities.deepClone(this.data);
913        return clone;
914    }
915
916    /**
917     * Creates a new series by copying a subset of the data in this time series.
918     *
919     * @param start  the index of the first item to copy.
920     * @param end  the index of the last item to copy.
921     *
922     * @return A series containing a copy of this series from start until end.
923     *
924     * @throws CloneNotSupportedException if there is a cloning problem.
925     */
926    public XYSeries createCopy(int start, int end)
927            throws CloneNotSupportedException {
928
929        XYSeries copy = (XYSeries) super.clone();
930        copy.data = new java.util.ArrayList();
931        if (this.data.size() > 0) {
932            for (int index = start; index <= end; index++) {
933                XYDataItem item = (XYDataItem) this.data.get(index);
934                XYDataItem clone = (XYDataItem) item.clone();
935                try {
936                    copy.add(clone);
937                }
938                catch (SeriesException e) {
939                    System.err.println("Unable to add cloned data item.");
940                }
941            }
942        }
943        return copy;
944
945    }
946
947    /**
948     * Tests this series for equality with an arbitrary object.
949     *
950     * @param obj  the object to test against for equality
951     *             (<code>null</code> permitted).
952     *
953     * @return A boolean.
954     */
955    public boolean equals(Object obj) {
956        if (obj == this) {
957            return true;
958        }
959        if (!(obj instanceof XYSeries)) {
960            return false;
961        }
962        if (!super.equals(obj)) {
963            return false;
964        }
965        XYSeries that = (XYSeries) obj;
966        if (this.maximumItemCount != that.maximumItemCount) {
967            return false;
968        }
969        if (this.autoSort != that.autoSort) {
970            return false;
971        }
972        if (this.allowDuplicateXValues != that.allowDuplicateXValues) {
973            return false;
974        }
975        if (!ObjectUtilities.equal(this.data, that.data)) {
976            return false;
977        }
978        return true;
979    }
980
981    /**
982     * Returns a hash code.
983     *
984     * @return A hash code.
985     */
986    public int hashCode() {
987        int result = super.hashCode();
988        // it is too slow to look at every data item, so let's just look at
989        // the first, middle and last items...
990        int count = getItemCount();
991        if (count > 0) {
992            XYDataItem item = getRawDataItem(0);
993            result = 29 * result + item.hashCode();
994        }
995        if (count > 1) {
996            XYDataItem item = getRawDataItem(count - 1);
997            result = 29 * result + item.hashCode();
998        }
999        if (count > 2) {
1000            XYDataItem item = getRawDataItem(count / 2);
1001            result = 29 * result + item.hashCode();
1002        }
1003        result = 29 * result + this.maximumItemCount;
1004        result = 29 * result + (this.autoSort ? 1 : 0);
1005        result = 29 * result + (this.allowDuplicateXValues ? 1 : 0);
1006        return result;
1007    }
1008
1009}
1010