private void checkPointsToJava2D(RectangleEdge edge, 
              Rectangle2D plotArea) {
          assertEquals("Left most point on the axis should be beginning of "
                  + "range.", plotArea.getX(), this.axis.valueToJava2D(
                  this.axis.getLowerBound(), plotArea, edge), EPSILON);
          assertEquals("Right most point on the axis should be end of range.", 
                  plotArea.getX() + plotArea.getWidth(), 
                  this.axis.valueToJava2D(this.axis.getUpperBound(), 
                  plotArea, edge), EPSILON);
          assertEquals("Center point on the axis should geometric mean of the bounds.", 
                  plotArea.getX() + (plotArea.getWidth() / 2), 
                  this.axis.valueToJava2D(Math.sqrt(this.axis.getLowerBound() 
                  * this.axis.getUpperBound()), plotArea, edge), EPSILON);