       1 /*
       2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
       3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
       4  *
       5  * This code is free software; you can redistribute it and/or modify it
       6  * under the terms of the GNU General Public License version 2 only, as
       7  * published by the Free Software Foundation.  Oracle designates this
       8  * particular file as subject to the "Classpath" exception as provided
       9  * by Oracle in the LICENSE file that accompanied this code.
      10  *
      11  * This code is distributed in the hope that it will be useful, but WITHOUT
      12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
      13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      14  * version 2 for more details (a copy is included in the LICENSE file that
      15  * accompanied this code).
      16  *
      17  * You should have received a copy of the GNU General Public License version
      18  * 2 along with this work; if not, write to the Free Software Foundation,
      19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
      20  *
      21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
      22  * or visit www.oracle.com if you need additional information or have any
      23  * questions.
      24  */
      25
      26 package javax.swing;
      27
      28 import java.util.EventListener;
      29 import java.util.BitSet;
      30 import java.io.Serializable;
      31 import java.beans.Transient;
      32
      33 import javax.swing.event.*;
      34
      35
      36 /**
      37  * Default data model for list selections.
      38  * <p>
      39  * <strong>Warning:</strong>
      40  * Serialized objects of this class will not be compatible with
      41  * future Swing releases. The current serialization support is
      42  * appropriate for short term storage or RMI between applications running
      43  * the same version of Swing.  As of 1.4, support for long term storage
      44  * of all JavaBeans&trade;
      45  * has been added to the <code>java.beans</code> package.
      46  * Please see {@link java.beans.XMLEncoder}.
      47  *
      48  * @author Philip Milne
      49  * @author Hans Muller
      50  * @see ListSelectionModel
      51  * @since 1.2
      52  */
      53 @SuppressWarnings("serial") // Same-version serialization only
      54 public class DefaultListSelectionModel implements ListSelectionModel, Cloneable, Serializable
      55 {
      56     private static final int MIN = -1;
      57     private static final int MAX = Integer.MAX_VALUE;
      58     private int selectionMode = MULTIPLE_INTERVAL_SELECTION;
      59     private int minIndex = MAX;
      60     private int maxIndex = MIN;
      61     private int anchorIndex = -1;
      62     private int leadIndex = -1;
      63     private int firstAdjustedIndex = MAX;
      64     private int lastAdjustedIndex = MIN;
      65     private boolean isAdjusting = false;
      66
      67     private int firstChangedIndex = MAX;
      68     private int lastChangedIndex = MIN;
      69
      70     private BitSet value = new BitSet(32);
      71     /**
      72      * The list of listeners.
      73      */
      74     protected EventListenerList listenerList = new EventListenerList();
      75
      76     /**
      77      * Whether or not the lead anchor notification is enabled.
      78      */
      79     protected boolean leadAnchorNotificationEnabled = true;
      80
      81     /** {@inheritDoc} */
      82     public int getMinSelectionIndex() { return isSelectionEmpty() ? -1 : minIndex; }
      83
      84     /** {@inheritDoc} */
      85     public int getMaxSelectionIndex() { return maxIndex; }
      86
      87     /** {@inheritDoc} */
      88     public boolean getValueIsAdjusting() { return isAdjusting; }
      89
      90     /** {@inheritDoc} */
      91     public int getSelectionMode() { return selectionMode; }
      92
      93     /**
      94      * {@inheritDoc}
      95      * @throws IllegalArgumentException {@inheritDoc}
      96      */
      97     public void setSelectionMode(int selectionMode) {
      98         int oldMode = this.selectionMode;
      99         switch (selectionMode) {
     100             case SINGLE_SELECTION:
     101             case SINGLE_INTERVAL_SELECTION:
     102             case MULTIPLE_INTERVAL_SELECTION:
     103                 this.selectionMode = selectionMode;
     104                 break;
     105             default:
     106                 throw new IllegalArgumentException("invalid selectionMode");
     107         }
     108
     109         /*
     110         This code will only be executed when selection needs to be updated on
     111         changing selection mode. It will happen only if selection mode is changed
     112         from MULTIPLE_INTERVAL to SINGLE_INTERVAL or SINGLE or from
     113         SINGLE_INTERVAL to SINGLE
     114          */
     115         if (oldMode > this.selectionMode) {
     116             if (this.selectionMode == SINGLE_SELECTION) {
     117                 if (!isSelectionEmpty()) {
     118                     setSelectionInterval(minIndex, minIndex);
     119                 }
     120             } else if (this.selectionMode == SINGLE_INTERVAL_SELECTION) {
     121                 if(!isSelectionEmpty()) {
     122                     int selectionEndindex = minIndex;
     123                     while (value.get(selectionEndindex + 1)) {
     124                         selectionEndindex++;
     125                     }
     126                     setSelectionInterval(minIndex, selectionEndindex);
     127                 }
     128             }
     129         }
     130     }
     131
     132     /** {@inheritDoc} */
     133     public boolean isSelectedIndex(int index) {
     134         return ((index < minIndex) || (index > maxIndex)) ? false : value.get(index);
     135     }
     136
     137     /** {@inheritDoc} */
     138     public boolean isSelectionEmpty() {
     139         return (minIndex > maxIndex);
     140     }
     141
     142     /** {@inheritDoc} */
     143     public void addListSelectionListener(ListSelectionListener l) {
     144         listenerList.add(ListSelectionListener.class, l);
     145     }
     146
     147     /** {@inheritDoc} */
     148     public void removeListSelectionListener(ListSelectionListener l) {
     149         listenerList.remove(ListSelectionListener.class, l);
     150     }
     151
     152     /**
     153      * Returns an array of all the list selection listeners
     154      * registered on this <code>DefaultListSelectionModel</code>.
     155      *
     156      * @return all of this model's <code>ListSelectionListener</code>s
     157      *         or an empty
     158      *         array if no list selection listeners are currently registered
     159      *
     160      * @see #addListSelectionListener
     161      * @see #removeListSelectionListener
     162      *
     163      * @since 1.4
     164      */
     165     public ListSelectionListener[] getListSelectionListeners() {
     166         return listenerList.getListeners(ListSelectionListener.class);
     167     }
     168
     169     /**
     170      * Notifies listeners that we have ended a series of adjustments.
     171      * @param isAdjusting true if this is the final change in a series of
     172      *          adjustments
     173      */
     174     protected void fireValueChanged(boolean isAdjusting) {
     175         if (lastChangedIndex == MIN) {
     176             return;
     177         }
     178         /* Change the values before sending the event to the
     179          * listeners in case the event causes a listener to make
     180          * another change to the selection.
     181          */
     182         int oldFirstChangedIndex = firstChangedIndex;
     183         int oldLastChangedIndex = lastChangedIndex;
     184         firstChangedIndex = MAX;
     185         lastChangedIndex = MIN;
     186         fireValueChanged(oldFirstChangedIndex, oldLastChangedIndex, isAdjusting);
     187     }
     188
     189
     190     /**
     191      * Notifies <code>ListSelectionListeners</code> that the value
     192      * of the selection, in the closed interval <code>firstIndex</code>,
     193      * <code>lastIndex</code>, has changed.
     194      *
     195      * @param firstIndex the first index in the interval
     196      * @param lastIndex the last index in the interval
     197      */
     198     protected void fireValueChanged(int firstIndex, int lastIndex) {
     199         fireValueChanged(firstIndex, lastIndex, getValueIsAdjusting());
     200     }
     201
     202     /**
     203      * @param firstIndex the first index in the interval
     204      * @param lastIndex the last index in the interval
     205      * @param isAdjusting true if this is the final change in a series of
     206      *          adjustments
     207      * @see EventListenerList
     208      */
     209     protected void fireValueChanged(int firstIndex, int lastIndex, boolean isAdjusting)
     210     {
     211         Object[] listeners = listenerList.getListenerList();
     212         ListSelectionEvent e = null;
     213
     214         for (int i = listeners.length - 2; i >= 0; i -= 2) {
     215             if (listeners[i] == ListSelectionListener.class) {
     216                 if (e == null) {
     217                     e = new ListSelectionEvent(this, firstIndex, lastIndex, isAdjusting);
     218                 }
     219                 ((ListSelectionListener)listeners[i+1]).valueChanged(e);
     220             }
     221         }
     222     }
     223
     224     private void fireValueChanged() {
     225         if (lastAdjustedIndex == MIN) {
     226             return;
     227         }
     228         /* If getValueAdjusting() is true, (eg. during a drag opereration)
     229          * record the bounds of the changes so that, when the drag finishes (and
     230          * setValueAdjusting(false) is called) we can post a single event
     231          * with bounds covering all of these individual adjustments.
     232          */
     233         if (getValueIsAdjusting()) {
     234             firstChangedIndex = Math.min(firstChangedIndex, firstAdjustedIndex);
     235             lastChangedIndex = Math.max(lastChangedIndex, lastAdjustedIndex);
     236         }
     237         /* Change the values before sending the event to the
     238          * listeners in case the event causes a listener to make
     239          * another change to the selection.
     240          */
     241         int oldFirstAdjustedIndex = firstAdjustedIndex;
     242         int oldLastAdjustedIndex = lastAdjustedIndex;
     243         firstAdjustedIndex = MAX;
     244         lastAdjustedIndex = MIN;
     245
     246         fireValueChanged(oldFirstAdjustedIndex, oldLastAdjustedIndex);
     247     }
     248
     249     /**
     250      * Returns an array of all the objects currently registered as
     251      * <code><em>Foo</em>Listener</code>s
     252      * upon this model.
     253      * <code><em>Foo</em>Listener</code>s
     254      * are registered using the <code>add<em>Foo</em>Listener</code> method.
     255      * <p>
     256      * You can specify the <code>listenerType</code> argument
     257      * with a class literal, such as <code><em>Foo</em>Listener.class</code>.
     258      * For example, you can query a <code>DefaultListSelectionModel</code>
     259      * instance <code>m</code>
     260      * for its list selection listeners
     261      * with the following code:
     262      *
     263      * <pre>ListSelectionListener[] lsls = (ListSelectionListener[])(m.getListeners(ListSelectionListener.class));</pre>
     264      *
     265      * If no such listeners exist,
     266      * this method returns an empty array.
     267      *
     268      * @param <T> the type of {@code EventListener} class being requested
     269      * @param listenerType  the type of listeners requested;
     270      *          this parameter should specify an interface
     271      *          that descends from <code>java.util.EventListener</code>
     272      * @return an array of all objects registered as
     273      *          <code><em>Foo</em>Listener</code>s
     274      *          on this model,
     275      *          or an empty array if no such
     276      *          listeners have been added
     277      * @exception ClassCastException if <code>listenerType</code> doesn't
     278      *          specify a class or interface that implements
     279      *          <code>java.util.EventListener</code>
     280      *
     281      * @see #getListSelectionListeners
     282      *
     283      * @since 1.3
     284      */
     285     public <T extends EventListener> T[] getListeners(Class<T> listenerType) {
     286         return listenerList.getListeners(listenerType);
     287     }
     288
     289     // Updates first and last change indices
     290     private void markAsDirty(int r) {
     291         if (r == -1) {
     292             return;
     293         }
     294
     295         firstAdjustedIndex = Math.min(firstAdjustedIndex, r);
     296         lastAdjustedIndex =  Math.max(lastAdjustedIndex, r);
     297     }
     298
     299     // Sets the state at this index and update all relevant state.
     300     private void set(int r) {
     301         if (value.get(r)) {
     302             return;
     303         }
     304         value.set(r);
     305         markAsDirty(r);
     306
     307         // Update minimum and maximum indices
     308         minIndex = Math.min(minIndex, r);
     309         maxIndex = Math.max(maxIndex, r);
     310     }
     311
     312     // Clears the state at this index and update all relevant state.
     313     private void clear(int r) {
     314         if (!value.get(r)) {
     315             return;
     316         }
     317         value.clear(r);
     318         markAsDirty(r);
     319
     320         // Update minimum and maximum indices
     321         /*
     322            If (r > minIndex) the minimum has not changed.
     323            The case (r < minIndex) is not possible because r'th value was set.
     324            We only need to check for the case when lowest entry has been cleared,
     325            and in this case we need to search for the first value set above it.
     326         */
     327         if (r == minIndex) {
     328             for(minIndex = minIndex + 1; minIndex <= maxIndex; minIndex++) {
     329                 if (value.get(minIndex)) {
     330                     break;
     331                 }
     332             }
     333         }
     334         /*
     335            If (r < maxIndex) the maximum has not changed.
     336            The case (r > maxIndex) is not possible because r'th value was set.
     337            We only need to check for the case when highest entry has been cleared,
     338            and in this case we need to search for the first value set below it.
     339         */
     340         if (r == maxIndex) {
     341             for(maxIndex = maxIndex - 1; minIndex <= maxIndex; maxIndex--) {
     342                 if (value.get(maxIndex)) {
     343                     break;
     344                 }
     345             }
     346         }
     347         /* Performance note: This method is called from inside a loop in
     348            changeSelection() but we will only iterate in the loops
     349            above on the basis of one iteration per deselected cell - in total.
     350            Ie. the next time this method is called the work of the previous
     351            deselection will not be repeated.
     352
     353            We also don't need to worry about the case when the min and max
     354            values are in their unassigned states. This cannot happen because
     355            this method's initial check ensures that the selection was not empty
     356            and therefore that the minIndex and maxIndex had 'real' values.
     357
     358            If we have cleared the whole selection, set the minIndex and maxIndex
     359            to their cannonical values so that the next set command always works
     360            just by using Math.min and Math.max.
     361         */
     362         if (isSelectionEmpty()) {
     363             minIndex = MAX;
     364             maxIndex = MIN;
     365         }
     366     }
     367
     368     /**
     369      * Sets the value of the leadAnchorNotificationEnabled flag.
     370      *
     371      * @param flag boolean value for {@code leadAnchorNotificationEnabled}
     372      * @see             #isLeadAnchorNotificationEnabled()
     373      */
     374     public void setLeadAnchorNotificationEnabled(boolean flag) {
     375         leadAnchorNotificationEnabled = flag;
     376     }
     377
     378     /**
     379      * Returns the value of the <code>leadAnchorNotificationEnabled</code> flag.
     380      * When <code>leadAnchorNotificationEnabled</code> is true the model
     381      * generates notification events with bounds that cover all the changes to
     382      * the selection plus the changes to the lead and anchor indices.
     383      * Setting the flag to false causes a narrowing of the event's bounds to
     384      * include only the elements that have been selected or deselected since
     385      * the last change. Either way, the model continues to maintain the lead
     386      * and anchor variables internally. The default is true.
     387      * <p>
     388      * Note: It is possible for the lead or anchor to be changed without a
     389      * change to the selection. Notification of these changes is often
     390      * important, such as when the new lead or anchor needs to be updated in
     391      * the view. Therefore, caution is urged when changing the default value.
     392      *
     393      * @return  the value of the <code>leadAnchorNotificationEnabled</code> flag
     394      * @see             #setLeadAnchorNotificationEnabled(boolean)
     395      */
     396     public boolean isLeadAnchorNotificationEnabled() {
     397         return leadAnchorNotificationEnabled;
     398     }
     399
     400     private void updateLeadAnchorIndices(int anchorIndex, int leadIndex) {
     401         if (leadAnchorNotificationEnabled) {
     402             if (this.anchorIndex != anchorIndex) {
     403                 markAsDirty(this.anchorIndex);
     404                 markAsDirty(anchorIndex);
     405             }
     406
     407             if (this.leadIndex != leadIndex) {
     408                 markAsDirty(this.leadIndex);
     409                 markAsDirty(leadIndex);
     410             }
     411         }
     412         this.anchorIndex = anchorIndex;
     413         this.leadIndex = leadIndex;
     414     }
     415
     416     private boolean contains(int a, int b, int i) {
     417         return (i >= a) && (i <= b);
     418     }
     419
     420     private void changeSelection(int clearMin, int clearMax,
     421                                  int setMin, int setMax, boolean clearFirst) {
     422         for(int i = Math.min(setMin, clearMin); i <= Math.max(setMax, clearMax); i++) {
     423
     424             boolean shouldClear = contains(clearMin, clearMax, i);
     425             boolean shouldSet = contains(setMin, setMax, i);
     426
     427             if (shouldSet && shouldClear) {
     428                 if (clearFirst) {
     429                     shouldClear = false;
     430                 }
     431                 else {
     432                     shouldSet = false;
     433                 }
     434             }
     435
     436             if (shouldSet) {
     437                 set(i);
     438             }
     439             if (shouldClear) {
     440                 clear(i);
     441             }
     442         }
     443         fireValueChanged();
     444     }
     445
     446    /**
     447     * Change the selection with the effect of first clearing the values
     448     * in the inclusive range [clearMin, clearMax] then setting the values
     449     * in the inclusive range [setMin, setMax]. Do this in one pass so
     450     * that no values are cleared if they would later be set.
     451     */
     452     private void changeSelection(int clearMin, int clearMax, int setMin, int setMax) {
     453         changeSelection(clearMin, clearMax, setMin, setMax, true);
     454     }
     455
     456     /** {@inheritDoc} */
     457     public void clearSelection() {
     458         removeSelectionIntervalImpl(minIndex, maxIndex, false);
     459     }
     460
     461     /**
     462      * Changes the selection to be between {@code index0} and {@code index1}
     463      * inclusive. {@code index0} doesn't have to be less than or equal to
     464      * {@code index1}.
     465      * <p>
     466      * In {@code SINGLE_SELECTION} selection mode, only the second index
     467      * is used.
     468      * <p>
     469      * If this represents a change to the current selection, then each
     470      * {@code ListSelectionListener} is notified of the change.
     471      * <p>
     472      * If either index is {@code -1}, this method does nothing and returns
     473      * without exception. Otherwise, if either index is less than {@code -1},
     474      * an {@code IndexOutOfBoundsException} is thrown.
     475      *
     476      * @param index0 one end of the interval.
     477      * @param index1 other end of the interval
     478      * @throws IndexOutOfBoundsException if either index is less than {@code -1}
     479      *         (and neither index is {@code -1})
     480      * @see #addListSelectionListener
     481      */
     482     public void setSelectionInterval(int index0, int index1) {
     483         if (index0 == -1 || index1 == -1) {
     484             return;
     485         }
     486
     487         if (getSelectionMode() == SINGLE_SELECTION) {
     488             index0 = index1;
     489         }
     490
     491         updateLeadAnchorIndices(index0, index1);
     492
     493         int clearMin = minIndex;
     494         int clearMax = maxIndex;
     495         int setMin = Math.min(index0, index1);
     496         int setMax = Math.max(index0, index1);
     497         changeSelection(clearMin, clearMax, setMin, setMax);
     498     }
     499
     500     /**
     501      * Changes the selection to be the set union of the current selection
     502      * and the indices between {@code index0} and {@code index1} inclusive.
     503      * <p>
     504      * In {@code SINGLE_SELECTION} selection mode, this is equivalent
     505      * to calling {@code setSelectionInterval}, and only the second index
     506      * is used. In {@code SINGLE_INTERVAL_SELECTION} selection mode, this
     507      * method behaves like {@code setSelectionInterval}, unless the given
     508      * interval is immediately adjacent to or overlaps the existing selection,
     509      * and can therefore be used to grow it.
     510      * <p>
     511      * If this represents a change to the current selection, then each
     512      * {@code ListSelectionListener} is notified of the change. Note that
     513      * {@code index0} doesn't have to be less than or equal to {@code index1}.
     514      * <p>
     515      * If either index is {@code -1}, this method does nothing and returns
     516      * without exception. Otherwise, if either index is less than {@code -1},
     517      * an {@code IndexOutOfBoundsException} is thrown.
     518      *
     519      * @param index0 one end of the interval.
     520      * @param index1 other end of the interval
     521      * @throws IndexOutOfBoundsException if either index is less than {@code -1}
     522      *         (and neither index is {@code -1})
     523      * @see #addListSelectionListener
     524      * @see #setSelectionInterval
     525      */
     526     public void addSelectionInterval(int index0, int index1)
     527     {
     528         if (index0 == -1 || index1 == -1) {
     529             return;
     530         }
     531
     532         // If we only allow a single selection, channel through
     533         // setSelectionInterval() to enforce the rule.
     534         if (getSelectionMode() == SINGLE_SELECTION) {
     535             setSelectionInterval(index0, index1);
     536             return;
     537         }
     538
     539         updateLeadAnchorIndices(index0, index1);
     540
     541         int clearMin = MAX;
     542         int clearMax = MIN;
     543         int setMin = Math.min(index0, index1);
     544         int setMax = Math.max(index0, index1);
     545
     546         // If we only allow a single interval and this would result
     547         // in multiple intervals, then set the selection to be just
     548         // the new range.
     549         if (getSelectionMode() == SINGLE_INTERVAL_SELECTION &&
     550                 (setMax < minIndex - 1 || setMin > maxIndex + 1)) {
     551
     552             setSelectionInterval(index0, index1);
     553             return;
     554         }
     555
     556         changeSelection(clearMin, clearMax, setMin, setMax);
     557     }
     558
     559
     560     /**
     561      * Changes the selection to be the set difference of the current selection
     562      * and the indices between {@code index0} and {@code index1} inclusive.
     563      * {@code index0} doesn't have to be less than or equal to {@code index1}.
     564      * <p>
     565      * In {@code SINGLE_INTERVAL_SELECTION} selection mode, if the removal
     566      * would produce two disjoint selections, the removal is extended through
     567      * the greater end of the selection. For example, if the selection is
     568      * {@code 0-10} and you supply indices {@code 5,6} (in any order) the
     569      * resulting selection is {@code 0-4}.
     570      * <p>
     571      * If this represents a change to the current selection, then each
     572      * {@code ListSelectionListener} is notified of the change.
     573      * <p>
     574      * If either index is {@code -1}, this method does nothing and returns
     575      * without exception. Otherwise, if either index is less than {@code -1},
     576      * an {@code IndexOutOfBoundsException} is thrown.
     577      *
     578      * @param index0 one end of the interval
     579      * @param index1 other end of the interval
     580      * @throws IndexOutOfBoundsException if either index is less than {@code -1}
     581      *         (and neither index is {@code -1})
     582      * @see #addListSelectionListener
     583      */
     584     public void removeSelectionInterval(int index0, int index1)
     585     {
     586         removeSelectionIntervalImpl(index0, index1, true);
     587     }
     588
     589     // private implementation allowing the selection interval
     590     // to be removed without affecting the lead and anchor
     591     private void removeSelectionIntervalImpl(int index0, int index1,
     592                                              boolean changeLeadAnchor) {
     593
     594         if (index0 == -1 || index1 == -1) {
     595             return;
     596         }
     597
     598         if (changeLeadAnchor) {
     599             updateLeadAnchorIndices(index0, index1);
     600         }
     601
     602         int clearMin = Math.min(index0, index1);
     603         int clearMax = Math.max(index0, index1);
     604         int setMin = MAX;
     605         int setMax = MIN;
     606
     607         // If the removal would produce to two disjoint selections in a mode
     608         // that only allows one, extend the removal to the end of the selection.
     609         if (getSelectionMode() != MULTIPLE_INTERVAL_SELECTION &&
     610                clearMin > minIndex && clearMax < maxIndex) {
     611             clearMax = maxIndex;
     612         }
     613
     614         changeSelection(clearMin, clearMax, setMin, setMax);
     615     }
     616
     617     private void setState(int index, boolean state) {
     618         if (state) {
     619             set(index);
     620         }
     621         else {
     622             clear(index);
     623         }
     624     }
     625
     626     /**
     627      * Insert length indices beginning before/after index. If the value
     628      * at index is itself selected and the selection mode is not
     629      * SINGLE_SELECTION, set all of the newly inserted items as selected.
     630      * Otherwise leave them unselected. This method is typically
     631      * called to sync the selection model with a corresponding change
     632      * in the data model.
     633      */
     634     public void insertIndexInterval(int index, int length, boolean before)
     635     {
     636         /* The first new index will appear at insMinIndex and the last
     637          * one will appear at insMaxIndex
     638          */
     639         int insMinIndex = (before) ? index : index + 1;
     640         int insMaxIndex = (insMinIndex + length) - 1;
     641
     642         /* Right shift the entire bitset by length, beginning with
     643          * index-1 if before is true, index+1 if it's false (i.e. with
     644          * insMinIndex).
     645          */
     646         for(int i = maxIndex; i >= insMinIndex; i--) {
     647             setState(i + length, value.get(i));
     648         }
     649
     650         /* Initialize the newly inserted indices.
     651          */
     652         boolean setInsertedValues = ((getSelectionMode() == SINGLE_SELECTION) ?
     653                                         false : value.get(index));
     654         for(int i = insMinIndex; i <= insMaxIndex; i++) {
     655             setState(i, setInsertedValues);
     656         }
     657
     658         int leadIndex = this.leadIndex;
     659         if (leadIndex > index || (before && leadIndex == index)) {
     660             leadIndex = this.leadIndex + length;
     661         }
     662         int anchorIndex = this.anchorIndex;
     663         if (anchorIndex > index || (before && anchorIndex == index)) {
     664             anchorIndex = this.anchorIndex + length;
     665         }
     666         if (leadIndex != this.leadIndex || anchorIndex != this.anchorIndex) {
     667             updateLeadAnchorIndices(anchorIndex, leadIndex);
     668         }
     669
     670         fireValueChanged();
     671     }
     672
     673
     674     /**
     675      * Remove the indices in the interval index0,index1 (inclusive) from
     676      * the selection model.  This is typically called to sync the selection
     677      * model width a corresponding change in the data model.  Note
     678      * that (as always) index0 need not be &lt;= index1.
     679      */
     680     public void removeIndexInterval(int index0, int index1)
     681     {
     682         int rmMinIndex = Math.min(index0, index1);
     683         int rmMaxIndex = Math.max(index0, index1);
     684         int gapLength = (rmMaxIndex - rmMinIndex) + 1;
     685
     686         /* Shift the entire bitset to the left to close the index0, index1
     687          * gap.
     688          */
     689         for(int i = rmMinIndex; i <= maxIndex; i++) {
     690             setState(i, value.get(i + gapLength));
     691         }
     692
     693         int leadIndex = this.leadIndex;
     694         if (leadIndex == 0 && rmMinIndex == 0) {
     695             // do nothing
     696         } else if (leadIndex > rmMaxIndex) {
     697             leadIndex = this.leadIndex - gapLength;
     698         } else if (leadIndex >= rmMinIndex) {
     699             leadIndex = rmMinIndex - 1;
     700         }
     701
     702         int anchorIndex = this.anchorIndex;
     703         if (anchorIndex == 0 && rmMinIndex == 0) {
     704             // do nothing
     705         } else if (anchorIndex > rmMaxIndex) {
     706             anchorIndex = this.anchorIndex - gapLength;
     707         } else if (anchorIndex >= rmMinIndex) {
     708             anchorIndex = rmMinIndex - 1;
     709         }
     710
     711         if (leadIndex != this.leadIndex || anchorIndex != this.anchorIndex) {
     712             updateLeadAnchorIndices(anchorIndex, leadIndex);
     713         }
     714
     715         fireValueChanged();
     716     }
     717
     718
     719     /** {@inheritDoc} */
     720     public void setValueIsAdjusting(boolean isAdjusting) {
     721         if (isAdjusting != this.isAdjusting) {
     722             this.isAdjusting = isAdjusting;
     723             this.fireValueChanged(isAdjusting);
     724         }
     725     }
     726
     727
     728     /**
     729      * Returns a string that displays and identifies this
     730      * object's properties.
     731      *
     732      * @return a <code>String</code> representation of this object
     733      */
     734     public String toString() {
     735         String s =  ((getValueIsAdjusting()) ? "~" : "=") + value.toString();
     736         return getClass().getName() + " " + Integer.toString(hashCode()) + " " + s;
     737     }
     738
     739     /**
     740      * Returns a clone of this selection model with the same selection.
     741      * <code>listenerLists</code> are not duplicated.
     742      *
     743      * @exception CloneNotSupportedException if the selection model does not
     744      *    both (a) implement the Cloneable interface and (b) define a
     745      *    <code>clone</code> method.
     746      */
     747     public Object clone() throws CloneNotSupportedException {
     748         DefaultListSelectionModel clone = (DefaultListSelectionModel)super.clone();
     749         clone.value = (BitSet)value.clone();
     750         clone.listenerList = new EventListenerList();
     751         return clone;
     752     }
     753
     754     /** {@inheritDoc} */
     755     @Transient
     756     public int getAnchorSelectionIndex() {
     757         return anchorIndex;
     758     }
     759
     760     /** {@inheritDoc} */
     761     @Transient
     762     public int getLeadSelectionIndex() {
     763         return leadIndex;
     764     }
     765
     766     /**
     767      * Set the anchor selection index, leaving all selection values unchanged.
     768      * If leadAnchorNotificationEnabled is true, send a notification covering
     769      * the old and new anchor cells.
     770      *
     771      * @see #getAnchorSelectionIndex
     772      * @see #setLeadSelectionIndex
     773      */
     774     public void setAnchorSelectionIndex(int anchorIndex) {
     775         updateLeadAnchorIndices(anchorIndex, this.leadIndex);
     776         fireValueChanged();
     777     }
     778
     779     /**
     780      * Set the lead selection index, leaving all selection values unchanged.
     781      * If leadAnchorNotificationEnabled is true, send a notification covering
     782      * the old and new lead cells.
     783      *
     784      * @param leadIndex the new lead selection index
     785      *
     786      * @see #setAnchorSelectionIndex
     787      * @see #setLeadSelectionIndex
     788      * @see #getLeadSelectionIndex
     789      *
     790      * @since 1.5
     791      */
     792     public void moveLeadSelectionIndex(int leadIndex) {
     793         // disallow a -1 lead unless the anchor is already -1
     794         if (leadIndex == -1) {
     795             if (this.anchorIndex != -1) {
     796                 return;
     797             }
     798
     799 /* PENDING(shannonh) - The following check is nice, to be consistent with
     800                        setLeadSelectionIndex. However, it is not absolutely
     801                        necessary: One could work around it by setting the anchor
     802                        to something valid, modifying the lead, and then moving
     803                        the anchor back to -1. For this reason, there's no sense
     804                        in adding it at this time, as that would require
     805                        updating the spec and officially committing to it.
     806
     807         // otherwise, don't do anything if the anchor is -1
     808         } else if (this.anchorIndex == -1) {
     809             return;
     810 */
     811
     812         }
     813
     814         updateLeadAnchorIndices(this.anchorIndex, leadIndex);
     815         fireValueChanged();
     816     }
     817
     818     /**
     819      * Sets the lead selection index, ensuring that values between the
     820      * anchor and the new lead are either all selected or all deselected.
     821      * If the value at the anchor index is selected, first clear all the
     822      * values in the range [anchor, oldLeadIndex], then select all the values
     823      * values in the range [anchor, newLeadIndex], where oldLeadIndex is the old
     824      * leadIndex and newLeadIndex is the new one.
     825      * <p>
     826      * If the value at the anchor index is not selected, do the same thing in
     827      * reverse selecting values in the old range and deselecting values in the
     828      * new one.
     829      * <p>
     830      * Generate a single event for this change and notify all listeners.
     831      * For the purposes of generating minimal bounds in this event, do the
     832      * operation in a single pass; that way the first and last index inside the
     833      * ListSelectionEvent that is broadcast will refer to cells that actually
     834      * changed value because of this method. If, instead, this operation were
     835      * done in two steps the effect on the selection state would be the same
     836      * but two events would be generated and the bounds around the changed
     837      * values would be wider, including cells that had been first cleared only
     838      * to later be set.
     839      * <p>
     840      * This method can be used in the <code>mouseDragged</code> method
     841      * of a UI class to extend a selection.
     842      *
     843      * @see #getLeadSelectionIndex
     844      * @see #setAnchorSelectionIndex
     845      */
     846     public void setLeadSelectionIndex(int leadIndex) {
     847         int anchorIndex = this.anchorIndex;
     848
     849         // only allow a -1 lead if the anchor is already -1
     850         if (leadIndex == -1) {
     851             if (anchorIndex == -1) {
     852                 updateLeadAnchorIndices(anchorIndex, leadIndex);
     853                 fireValueChanged();
     854             }
     855
     856             return;
     857         // otherwise, don't do anything if the anchor is -1
     858         } else if (anchorIndex == -1) {
     859             return;
     860         }
     861
     862         if (this.leadIndex == -1) {
     863             this.leadIndex = leadIndex;
     864         }
     865
     866         boolean shouldSelect = value.get(this.anchorIndex);
     867
     868         if (getSelectionMode() == SINGLE_SELECTION) {
     869             anchorIndex = leadIndex;
     870             shouldSelect = true;
     871         }
     872
     873         int oldMin = Math.min(this.anchorIndex, this.leadIndex);
     874         int oldMax = Math.max(this.anchorIndex, this.leadIndex);
     875         int newMin = Math.min(anchorIndex, leadIndex);
     876         int newMax = Math.max(anchorIndex, leadIndex);
     877
     878         updateLeadAnchorIndices(anchorIndex, leadIndex);
     879
     880         if (shouldSelect) {
     881             changeSelection(oldMin, oldMax, newMin, newMax);
     882         }
     883         else {
     884             changeSelection(newMin, newMax, oldMin, oldMax, false);
     885         }
     886     }
     887 }