question: protected void selectAutoTickUnit ( Graphics2D g2 , Rectangle2D dataArea , RectangleEdge edge ) { if ( RectangleEdge . isTopOrBottom ( edge ) ) { selectHorizontalAutoTickUnit ( g2 , dataArea , edge ) ; } else if ( RectangleEdge . isLeftOrRight ( edge ) ) { selectVerticalAutoTickUnit ( g2 , dataArea , edge ) ; } }
target:  Selects an appropriate tick value for the axis.  The strategy is to display as many ticks as possible (selected from an array of 'standard' tick units) without the labels overlapping.