/* SingleSelectionModel.java --
Copyright (C) 2002, 2004 Free Software Foundation, Inc.
This file is part of GNU Classpath.
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package javax.swing;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
/**
* A data model that is used in components that support at most one
* selected element, like {@link JTabbedPane}, {@link JMenu} and
* {@link JPopupMenu}.
*
* @author Andrew Selkirk
*/
public interface SingleSelectionModel
{
/**
* Returns the selected index or <code>-1</code> if there is no selection.
*
* @return The selected index.
*
* @see #setSelectedIndex(int)
*/
int getSelectedIndex();
/**
* Sets the selected index and, if this is different to the previous
* selection, sends a {@link ChangeEvent} to all registered listeners.
*
* @param index the index (use <code>-1</code> to represent no selection).
*
* @see #getSelectedIndex()
* @see #clearSelection
*/
void setSelectedIndex(int index);
/**
* Clears the selection by setting the selected index to <code>-1</code> and
* sends a {@link ChangeEvent} to all registered listeners. If the selected
* index is already <code>-1</code>, this method does nothing.
*/
void clearSelection();
/**
* Returns <code>true</code> if there is a selection, and <code>false</code>
* otherwise.
*
* @return A boolean.
*/
boolean isSelected();
/**
* Registers a listener to receive {@link ChangeEvent} notifications from
* this model whenever the selected index changes.
*
* @param listener the listener to add.
*/
void addChangeListener(ChangeListener listener);
/**
* Deregisters a listener so that it no longer receives {@link ChangeEvent}
* notifications from this model.
*
* @param listener the listener to remove.
*/
void removeChangeListener(ChangeListener listener);
}