/*
* This file is part of the Echo Web Application Framework (hereinafter "Echo").
* Copyright (C) 2002-2009 NextApp, Inc.
*
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*/
package nextapp.echo2.app.list;
import java.io.Serializable;
import java.util.BitSet;
import java.util.EventListener;
import nextapp.echo2.app.event.EventListenerList;
import nextapp.echo2.app.event.ChangeEvent;
import nextapp.echo2.app.event.ChangeListener;
/**
* Default <code>ListSelectionModel</code> implementation.
*/
public class DefaultListSelectionModel
implements ListSelectionModel, Serializable {
private EventListenerList listenerList = new EventListenerList();
private int selectionMode = SINGLE_SELECTION;
private BitSet selection = new BitSet();
private int minSelectedIndex = -1;
/**
* @see nextapp.echo2.app.list.ListSelectionModel#addChangeListener(
* nextapp.echo2.app.event.ChangeListener)
*/
public void addChangeListener(ChangeListener l) {
listenerList.addListener(ChangeListener.class, l);
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#clearSelection()
*/
public void clearSelection() {
selection = new BitSet();
minSelectedIndex = -1;
fireValueChanged();
}
/**
* Notifies <code>ChangeListener</code>s that the selection has
* changed.
*/
protected void fireValueChanged() {
ChangeEvent e = new ChangeEvent(this);
EventListener[] listeners = listenerList.getListeners(ChangeListener.class);
for (int index = 0; index < listeners.length; ++index) {
((ChangeListener) listeners[index]).stateChanged(e);
}
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#getMaxSelectedIndex()
*/
public int getMaxSelectedIndex() {
return selection.length() - 1;
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#getMinSelectedIndex()
*/
public int getMinSelectedIndex() {
return minSelectedIndex;
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#getSelectionMode()
*/
public int getSelectionMode() {
return selectionMode;
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#isSelectedIndex(int)
*/
public boolean isSelectedIndex(int index) {
return selection.get(index);
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#isSelectionEmpty()
*/
public boolean isSelectionEmpty() {
return selection.length() == 0;
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#removeChangeListener(nextapp.echo2.app.event.ChangeListener)
*/
public void removeChangeListener(ChangeListener l) {
listenerList.removeListener(ChangeListener.class, l);
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#setSelectedIndex(int, boolean)
*/
public void setSelectedIndex(int index, boolean newValue) {
boolean oldValue = isSelectedIndex(index);
if (newValue ^ oldValue) {
if (newValue) {
if (selectionMode == SINGLE_SELECTION && getMinSelectedIndex() != -1) {
setSelectedIndex(getMinSelectedIndex(), false);
}
selection.set(index);
if (index < minSelectedIndex || minSelectedIndex == -1) {
minSelectedIndex = index;
}
} else {
selection.clear(index);
if (index == minSelectedIndex) {
// Minimum selected index has been deselected, find new minimum selected index.
int max = getMaxSelectedIndex();
minSelectedIndex = -1;
for (int i = 0; i <= max; ++i) {
if (selection.get(i)) {
minSelectedIndex = i;
break;
}
}
}
}
fireValueChanged();
}
}
/**
* @see nextapp.echo2.app.list.ListSelectionModel#setSelectionMode(int)
*/
public void setSelectionMode(int selectionMode) {
if (selectionMode != MULTIPLE_SELECTION && this.selectionMode == MULTIPLE_SELECTION) {
// deselect all but first selected element.
int maxSelectedIndex = getMaxSelectedIndex();
for (int i = minSelectedIndex + 1; i <= maxSelectedIndex; ++i) {
setSelectedIndex(i, false);
}
}
this.selectionMode = selectionMode;
fireValueChanged();
}
}