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	/*
	* Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package javax.swing;

	import java.util.*;

	import java.io.Serializable;

	/**
	* The default model for combo boxes.
	*
	* @param <E> the type of the elements of this model
	*
	* @author Arnaud Weber
	* @author Tom Santos
	*/

	public class DefaultComboBoxModel<E> extends AbstractListModel<E> implements MutableComboBoxModel<E>, Serializable {
	Vector<E> objects;
	Object selectedObject;

	/**
	* Constructs an empty DefaultComboBoxModel object.
	*/
	public DefaultComboBoxModel() {
	objects = new Vector<E>();
	}

	/**
	* Constructs a DefaultComboBoxModel object initialized with
	* an array of objects.
	*
	* @param items an array of Object objects
	*/
	public DefaultComboBoxModel(final E items[]) {
	objects = new Vector<E>(items.length);

	int i,c;
	for ( i=0,c=items.length;i<c;i++ )
	objects.addElement(items[i]);

	if ( getSize() > 0 ) {
	selectedObject = getElementAt( 0 );
	}
	}

	/**
	* Constructs a DefaultComboBoxModel object initialized with
	* a vector.
	*
	* @param v a Vector object ...
	*/
	public DefaultComboBoxModel(Vector<E> v) {
	objects = v;

	if ( getSize() > 0 ) {
	selectedObject = getElementAt( 0 );
	}
	}

	// implements javax.swing.ComboBoxModel
	/**
	* Set the value of the selected item. The selected item may be null.
	*
	* @param anObject The combo box value or null for no selection.
	*/
	public void setSelectedItem(Object anObject) {
	if ((selectedObject != null && !selectedObject.equals( anObject )) \|\|
	selectedObject == null && anObject != null) {
	selectedObject = anObject;
	fireContentsChanged(this, -1, -1);
	}
	}

	// implements javax.swing.ComboBoxModel
	public Object getSelectedItem() {
	return selectedObject;
	}

	// implements javax.swing.ListModel
	public int getSize() {
	return objects.size();
	}

	// implements javax.swing.ListModel
	public E getElementAt(int index) {
	if ( index >= 0 && index < objects.size() )
	return objects.elementAt(index);
	else
	return null;
	}

	/**
	* Returns the index-position of the specified object in the list.
	*
	* @param anObject
	* @return an int representing the index position, where 0 is
	* the first position
	*/
	public int getIndexOf(Object anObject) {
	return objects.indexOf(anObject);
	}

	// implements javax.swing.MutableComboBoxModel
	public void addElement(E anObject) {
	objects.addElement(anObject);
	fireIntervalAdded(this,objects.size()-1, objects.size()-1);
	if ( objects.size() == 1 && selectedObject == null && anObject != null ) {
	setSelectedItem( anObject );
	}
	}

	// implements javax.swing.MutableComboBoxModel
	public void insertElementAt(E anObject,int index) {
	objects.insertElementAt(anObject,index);
	fireIntervalAdded(this, index, index);
	}

	// implements javax.swing.MutableComboBoxModel
	public void removeElementAt(int index) {
	if ( getElementAt( index ) == selectedObject ) {
	if ( index == 0 ) {
	setSelectedItem( getSize() == 1 ? null : getElementAt( index + 1 ) );
	}
	else {
	setSelectedItem( getElementAt( index - 1 ) );
	}
	}

	objects.removeElementAt(index);

	fireIntervalRemoved(this, index, index);
	}

	// implements javax.swing.MutableComboBoxModel
	public void removeElement(Object anObject) {
	int index = objects.indexOf(anObject);
	if ( index != -1 ) {
	removeElementAt(index);
	}
	}

	/**
	* Empties the list.
	*/
	public void removeAllElements() {
	if ( objects.size() > 0 ) {
	int firstIndex = 0;
	int lastIndex = objects.size() - 1;
	objects.removeAllElements();
	selectedObject = null;
	fireIntervalRemoved(this, firstIndex, lastIndex);
	} else {
	selectedObject = null;
	}
	}
	}

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