uiBindingRegistry.registerFirstMouseDragMode( new ColumnResizeEventMatcher( SWT.NONE,
                  GridRegion.COLUMN_HEADER, 1 ), new XColumnResizeDragMode() );

public class XColumnResizeDragMode implements IDragMode
{
  private int              m_column;
  private int              m_originalWidth;
  private int              m_originalX;

  private static final int MIN_COLUMN_WIDTH = 25;

  /****************************************** mouseDown ******************************************/
  @Override
  public void mouseDown( NatTable nattable, MouseEvent event )
  {
    // determine which column is being resized
    nattable.forceFocus();
    m_column = CellEdgeDetectUtil.getColumnPositionToResize( nattable, new Point( event.x, event.y ) );

    if ( m_column >= 0 )
    {
      m_originalWidth = nattable.getColumnWidthByPosition( m_column );
      m_originalX = event.x;
    }
  }

  /****************************************** mouseMove ******************************************/
  @Override
  public void mouseMove( NatTable nattable, MouseEvent event )
  {
    // determine new width
    int width = m_originalWidth + event.x - m_originalX;

    // don't allow width to go below minimum
    if ( width < MIN_COLUMN_WIDTH )
      width = MIN_COLUMN_WIDTH;

    // update table column width and trigger redraw
    nattable.doCommand( new ColumnResizeCommand( nattable, m_column, width ) );
    nattable.redraw();
  }

  /******************************************* mouseUp *******************************************/
  @Override
  public void mouseUp( NatTable nattable, MouseEvent event )
  {
    // nothing to do
  }

}