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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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*/
package javax.swing;
import java.util.Collection;
import java.util.Vector;
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
* @since 1.2
*/
@SuppressWarnings("serial") // Superclass is not serializable across versions
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 the object to return the index of
* @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;
}
}
/**
* Adds all of the elements present in the collection.
*
* @param c the collection which contains the elements to add
* @throws NullPointerException if {@code c} is null
*/
public void addAll(Collection<? extends E> c) {
if (c.isEmpty()) {
return;
}
int startIndex = getSize();
objects.addAll(c);
fireIntervalAdded(this, startIndex, getSize() - 1);
}
/**
* Adds all of the elements present in the collection, starting
* from the specified index.
*
* @param index index at which to insert the first element from the
* specified collection
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