SortedComboBoxModel.java

/*
 *  Custom model to make sure the items are stored in a sorted order.
 *  The default is to sort in the natural order of the item, but a
 *  Comparator can be used to customize the sort order.
 *  
 *  Created by Rob Camick http://tips4java.wordpress.com/
 */
package mekhq.gui.model;

import java.util.Comparator;
import java.util.Vector;

import javax.swing.DefaultComboBoxModel;

public class SortedComboBoxModel<E> extends DefaultComboBoxModel<E> {

	/**
	 * 
	 */
	private static final long serialVersionUID = 3728158859609424148L;
	private Comparator<E> comparator;

	/*
	 *  Create an empty model that will use the natural sort order of the item
	 */
	public SortedComboBoxModel()
	{
		super();
	}

	/*
	 *  Create an empty model that will use the specified Comparator
	 */
	public SortedComboBoxModel(Comparator<E> comparator)
	{
		super();
		this.comparator = comparator;
	}

	/*
	 *	Create a model with data and use the nature sort order of the items
	 */
	public SortedComboBoxModel(E items[])
	{
		this( items, null );
	}

	/*
	 *  Create a model with data and use the specified Comparator
	 */
	public SortedComboBoxModel(E items[], Comparator<E> comparator)
	{
		this.comparator = comparator;

		for (E item : items)
		{
            addElement(item);
        }
	}

	/*
	 *	Create a model with data and use the nature sort order of the items
	 */
	public SortedComboBoxModel(Vector<E> items)
	{
		this( items, null );
	}

	/*
	 *  Create a model with data and use the specified Comparator
	 */
	public SortedComboBoxModel(Vector<E> items, Comparator<E> comparator)
	{
		this.comparator = comparator;

		for (E item : items)
		{
            addElement( item );
        }
	}

	@Override
	public void addElement(E element)
	{
		insertElementAt(element, 0);
	}

	@SuppressWarnings("unchecked")
	@Override
	public void insertElementAt(E element, int index)
	{
		int size = getSize();

		//  Determine where to insert element to keep model in sorted order
		for (index = 0; index < size; index++)
		{
			if (comparator != null)
			{
				E o = getElementAt( index );

				if (comparator.compare(o, element) > 0)
					break;
			}
			else
			{
				Comparable<E> c = (Comparable<E>)getElementAt(index);
				if (c.compareTo(element) > 0)
					break;
			}
		}

		super.insertElementAt(element, index);

		//  Select an element when it is added to the beginning of the model
		if (index == 0 && element != null)
		{
			setSelectedItem( element );
		}
	}

}