Review

StatisticalCategoryDataset.getStDevValue() may return null.

Check for null.

• missing/condition/null_check

org/jfree/chart/renderer/category/StatisticalBarRenderer.java

drawVerticalItem(Graphics2D, CategoryItemRendererState, Rectangle2D, CategoryPlot, CategoryAxis, ValueAxis, StatisticalCategoryDataset, int, int)

class StatisticalBarRenderer {
    /**
     * Draws an item for a plot with a vertical orientation.
     * 
     * @param g2  the graphics device.
     * @param state  the renderer state.
     * @param dataArea  the data area.
     * @param plot  the plot.
     * @param domainAxis  the domain axis.
     * @param rangeAxis  the range axis.
     * @param dataset  the data.
     * @param row  the row index (zero-based).
     * @param column  the column index (zero-based).
     */
    protected void drawVerticalItem(Graphics2D g2,
                                    CategoryItemRendererState state,
                                    Rectangle2D dataArea,
                                    CategoryPlot plot,
                                    CategoryAxis domainAxis,
                                    ValueAxis rangeAxis,
                                    StatisticalCategoryDataset dataset,
                                    int row,
                                    int column) {
                                     
        RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
        
        // BAR X
        double rectX = domainAxis.getCategoryStart(
            column, getColumnCount(), dataArea, xAxisLocation
        );

        int seriesCount = getRowCount();
        int categoryCount = getColumnCount();
        if (seriesCount > 1) {
            double seriesGap = dataArea.getWidth() * getItemMargin()
                               / (categoryCount * (seriesCount - 1));
            rectX = rectX + row * (state.getBarWidth() + seriesGap);
        }
        else {
            rectX = rectX + row * state.getBarWidth();
        }

        // BAR Y
        Number meanValue = dataset.getMeanValue(row, column);

        double value = meanValue.doubleValue();
        double base = 0.0;
        double lclip = getLowerClip();
        double uclip = getUpperClip();

        if (uclip <= 0.0) {  // cases 1, 2, 3 and 4
            if (value >= uclip) {
                return; // bar is not visible
            }
            base = uclip;
            if (value <= lclip) {
                value = lclip;
            }
        }
        else if (lclip <= 0.0) { // cases 5, 6, 7 and 8
            if (value >= uclip) {
                value = uclip;
            }
            else {
                if (value <= lclip) {
                    value = lclip;
                }
            }
        }
        else { // cases 9, 10, 11 and 12
            if (value <= lclip) {
                return; // bar is not visible
            }
            base = getLowerClip();
            if (value >= uclip) {
               value = uclip;
            }
        }

        RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
        double transY1 = rangeAxis.valueToJava2D(base, dataArea, yAxisLocation);
        double transY2 = rangeAxis.valueToJava2D(value, dataArea, 
                yAxisLocation);
        double rectY = Math.min(transY2, transY1);

        double rectWidth = state.getBarWidth();
        double rectHeight = Math.abs(transY2 - transY1);

        Rectangle2D bar = new Rectangle2D.Double(rectX, rectY, rectWidth, 
                rectHeight);
        Paint seriesPaint = getItemPaint(row, column);
        g2.setPaint(seriesPaint);
        g2.fill(bar);
        if (isDrawBarOutline() && state.getBarWidth() > 3) {
            g2.setStroke(getItemStroke(row, column));
            g2.setPaint(getItemOutlinePaint(row, column));
            g2.draw(bar);
        }

        // standard deviation lines
        double valueDelta = dataset.getStdDevValue(row, column).doubleValue();
        double highVal = rangeAxis.valueToJava2D(meanValue.doubleValue() 
                + valueDelta, dataArea, yAxisLocation);
        double lowVal = rangeAxis.valueToJava2D(meanValue.doubleValue() 
                - valueDelta, dataArea, yAxisLocation);

        if (this.errorIndicatorStroke != null) {
            g2.setStroke(this.errorIndicatorStroke);
        }
        else {
            g2.setStroke(getItemOutlineStroke(row, column));
        }
        if (this.errorIndicatorPaint != null) {
            g2.setPaint(this.errorIndicatorPaint);  
        }
        else {
            g2.setPaint(getItemOutlinePaint(row, column));   
        }
        Line2D line = null;
        line = new Line2D.Double(rectX + rectWidth / 2.0d, lowVal,
                                 rectX + rectWidth / 2.0d, highVal);
        g2.draw(line);
        line = new Line2D.Double(rectX + rectWidth / 2.0d - 5.0d, highVal,
                                 rectX + rectWidth / 2.0d + 5.0d, highVal);
        g2.draw(line);
        line = new Line2D.Double(rectX + rectWidth / 2.0d - 5.0d, lowVal,
                                 rectX + rectWidth / 2.0d + 5.0d, lowVal);
        g2.draw(line);
        
        CategoryItemLabelGenerator generator = getItemLabelGenerator(row, 
                column);
        if (generator != null && isItemLabelVisible(row, column)) {
            drawItemLabel(g2, dataset, row, column, plot, generator, bar, 
                (value < 0.0));
        }        

        // add an item entity, if this information is being collected
        EntityCollection entities = state.getEntityCollection();
        if (entities != null) {
            addItemEntity(entities, dataset, row, column, bar);
        }
    }

}

class CheckStdDevValueNull {
  void pattern(StatisticalCategoryDataset dataset, int row, int column) {
    Number n = dataset.getStdDevValue(row, column);
    if (n != null) {
      n.doubleValue();
    }
  }
}