barrenderer.java

jfreechart-1.0.12.zip 可以用来作图

    }

    /**
     * Returns the upper clip value.  This value is recalculated in the
     * initialise() method.
     *
     * @return The value.
     */
    public double getUpperClip() {
        // TODO:  this attribute should be transferred to the renderer state.
        return this.upperClip;
    }

    /**
     * Initialises the renderer and returns a state object that will be passed
     * to subsequent calls to the drawItem method.  This method gets called
     * once at the start of the process of drawing a chart.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area in which the data is to be plotted.
     * @param plot  the plot.
     * @param rendererIndex  the renderer index.
     * @param info  collects chart rendering information for return to caller.
     *
     * @return The renderer state.
     */
    public CategoryItemRendererState initialise(Graphics2D g2,
                                                Rectangle2D dataArea,
                                                CategoryPlot plot,
                                                int rendererIndex,
                                                PlotRenderingInfo info) {

        CategoryItemRendererState state = super.initialise(g2, dataArea, plot,
                rendererIndex, info);

        // get the clipping values...
        ValueAxis rangeAxis = plot.getRangeAxisForDataset(rendererIndex);
        this.lowerClip = rangeAxis.getRange().getLowerBound();
        this.upperClip = rangeAxis.getRange().getUpperBound();

        // calculate the bar width
        calculateBarWidth(plot, dataArea, rendererIndex, state);

        return state;

    }

    /**
     * Calculates the bar width and stores it in the renderer state.
     *
     * @param plot  the plot.
     * @param dataArea  the data area.
     * @param rendererIndex  the renderer index.
     * @param state  the renderer state.
     */
    protected void calculateBarWidth(CategoryPlot plot,
                                     Rectangle2D dataArea,
                                     int rendererIndex,
                                     CategoryItemRendererState state) {

        CategoryAxis domainAxis = getDomainAxis(plot, rendererIndex);
        CategoryDataset dataset = plot.getDataset(rendererIndex);
        if (dataset != null) {
            int columns = dataset.getColumnCount();
            int rows = dataset.getRowCount();
            double space = 0.0;
            PlotOrientation orientation = plot.getOrientation();
            if (orientation == PlotOrientation.HORIZONTAL) {
                space = dataArea.getHeight();
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                space = dataArea.getWidth();
            }
            double maxWidth = space * getMaximumBarWidth();
            double categoryMargin = 0.0;
            double currentItemMargin = 0.0;
            if (columns > 1) {
                categoryMargin = domainAxis.getCategoryMargin();
            }
            if (rows > 1) {
                currentItemMargin = getItemMargin();
            }
            double used = space * (1 - domainAxis.getLowerMargin()
                                     - domainAxis.getUpperMargin()
                                     - categoryMargin - currentItemMargin);
            if ((rows * columns) > 0) {
                state.setBarWidth(Math.min(used / (rows * columns), maxWidth));
            }
            else {
                state.setBarWidth(Math.min(used, maxWidth));
            }
        }
    }

    /**
     * Calculates the coordinate of the first "side" of a bar.  This will be
     * the minimum x-coordinate for a vertical bar, and the minimum
     * y-coordinate for a horizontal bar.
     *
     * @param plot  the plot.
     * @param orientation  the plot orientation.
     * @param dataArea  the data area.
     * @param domainAxis  the domain axis.
     * @param state  the renderer state (has the bar width precalculated).
     * @param row  the row index.
     * @param column  the column index.
     *
     * @return The coordinate.
     */
    protected double calculateBarW0(CategoryPlot plot,
                                    PlotOrientation orientation,
                                    Rectangle2D dataArea,
                                    CategoryAxis domainAxis,
                                    CategoryItemRendererState state,
                                    int row,
                                    int column) {
        // calculate bar width...
        double space = 0.0;
        if (orientation == PlotOrientation.HORIZONTAL) {
            space = dataArea.getHeight();
        }
        else {
            space = dataArea.getWidth();
        }
        double barW0 = domainAxis.getCategoryStart(column, getColumnCount(),
                dataArea, plot.getDomainAxisEdge());
        int seriesCount = getRowCount();
        int categoryCount = getColumnCount();
        if (seriesCount > 1) {
            double seriesGap = space * getItemMargin()
                               / (categoryCount * (seriesCount - 1));
            double seriesW = calculateSeriesWidth(space, domainAxis,
                    categoryCount, seriesCount);
            barW0 = barW0 + row * (seriesW + seriesGap)
                          + (seriesW / 2.0) - (state.getBarWidth() / 2.0);
        }
        else {
            barW0 = domainAxis.getCategoryMiddle(column, getColumnCount(),
                    dataArea, plot.getDomainAxisEdge()) - state.getBarWidth()
                    / 2.0;
        }
        return barW0;
    }

    /**
     * Calculates the coordinates for the length of a single bar.
     *
     * @param value  the value represented by the bar.
     *
     * @return The coordinates for each end of the bar (or <code>null</code> if
     *         the bar is not visible for the current axis range).
     */
    protected double[] calculateBarL0L1(double value) {
        double lclip = getLowerClip();
        double uclip = getUpperClip();
        double barLow = Math.min(this.base, value);
        double barHigh = Math.max(this.base, value);
        if (barHigh < lclip) {  // bar is not visible
            return null;
        }
        if (barLow > uclip) {   // bar is not visible
            return null;
        }
        barLow = Math.max(barLow, lclip);
        barHigh = Math.min(barHigh, uclip);
        return new double[] {barLow, barHigh};
    }

    /**
     * Returns the range of values the renderer requires to display all the
     * items from the specified dataset.  This takes into account the range
     * of values in the dataset, plus the flag that determines whether or not
     * the base value for the bars should be included in the range.
     *
     * @param dataset  the dataset (<code>null</code> permitted).
     *
     * @return The range (or <code>null</code> if the dataset is
     *         <code>null</code> or empty).
     */
    public Range findRangeBounds(CategoryDataset dataset) {
        if (dataset == null) {
            return null;
        }
        Range result = DatasetUtilities.findRangeBounds(dataset);
        if (result != null) {
            if (this.includeBaseInRange) {
                result = Range.expandToInclude(result, this.base);
            }
        }
        return result;
    }

    /**
     * Returns a legend item for a series.
     *
     * @param datasetIndex  the dataset index (zero-based).
     * @param series  the series index (zero-based).
     *
     * @return The legend item (possibly <code>null</code>).
     */
    public LegendItem getLegendItem(int datasetIndex, int series) {

        CategoryPlot cp = getPlot();
        if (cp == null) {
            return null;
        }

        // check that a legend item needs to be displayed...
        if (!isSeriesVisible(series) || !isSeriesVisibleInLegend(series)) {
            return null;
        }

        CategoryDataset dataset = cp.getDataset(datasetIndex);
        String label = getLegendItemLabelGenerator().generateLabel(dataset,
                series);
        String description = label;
        String toolTipText = null;
        if (getLegendItemToolTipGenerator() != null) {
            toolTipText = getLegendItemToolTipGenerator().generateLabel(
                    dataset, series);
        }
        String urlText = null;
        if (getLegendItemURLGenerator() != null) {
            urlText = getLegendItemURLGenerator().generateLabel(dataset,
                    series);
        }
        Shape shape = lookupLegendShape(series);
        Paint paint = lookupSeriesPaint(series);
        Paint outlinePaint = lookupSeriesOutlinePaint(series);
        Stroke outlineStroke = lookupSeriesOutlineStroke(series);

        LegendItem result = new LegendItem(label, description, toolTipText,
                urlText, true, shape, true, paint, isDrawBarOutline(),
                outlinePaint, outlineStroke, false, new Line2D.Float(),
                new BasicStroke(1.0f), Color.black);
        result.setLabelFont(lookupLegendTextFont(series));
        Paint labelPaint = lookupLegendTextPaint(series);
        if (labelPaint != null) {
            result.setLabelPaint(labelPaint);
        }
        result.setDataset(dataset);
        result.setDatasetIndex(datasetIndex);
        result.setSeriesKey(dataset.getRowKey(series));
        result.setSeriesIndex(series);
        if (this.gradientPaintTransformer != null) {
            result.setFillPaintTransformer(this.gradientPaintTransformer);
        }
        return result;
    }

    /**
     * Draws the bar for a single (series, category) data item.
     *
     * @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 dataset.
     * @param row  the row index (zero-based).
     * @param column  the column index (zero-based).
     * @param pass  the pass index.
     */
    public void drawItem(Graphics2D g2,
                         CategoryItemRendererState state,
                         Rectangle2D dataArea,
                         CategoryPlot plot,
                         CategoryAxis domainAxis,
                         ValueAxis rangeAxis,
                         CategoryDataset dataset,
                         int row,
                         int column,
                         int pass) {

        // nothing is drawn for null values...
        Number dataValue = dataset.getValue(row, column);
        if (dataValue == null) {
            return;
        }

        final double value = dataValue.doubleValue();
        PlotOrientation orientation = plot.getOrientation();
        double barW0 = calculateBarW0(plot, orientation, dataArea, domainAxis,
                state, row, column);
        double[] barL0L1 = calculateBarL0L1(value);
        if (barL0L1 == null) {
            return;  // the bar is not visible
        }

        RectangleEdge edge = plot.getRangeAxisEdge();
        double transL0 = rangeAxis.valueToJava2D(barL0L1[0], dataArea, edge);
        double transL1 = rangeAxis.valueToJava2D(barL0L1[1], dataArea, edge);

        // in the following code, barL0 is (in Java2D coordinates) the LEFT
        // end of the bar for a horizontal bar chart, and the TOP end of the
        // bar for a vertical bar chart.  Whether this is the BASE of the bar
        // or not depends also on (a) whether the data value is 'negative'
        // relative to the base value and (b) whether or not the range axis is
        // inverted.  This only matters if/when we apply the minimumBarLength
        // attribute, because we should extend the non-base end of the bar
        boolean positive = (value >= this.base);
        boolean inverted = rangeAxis.isInverted();
        double barL0 = Math.min(transL0, transL1);
        double barLength = Math.abs(transL1 - transL0);
        double barLengthAdj = 0.0;
        if (barLength > 0.0 && barLength < getMinimumBarLength()) {
            barLengthAdj = getMinimumBarLength() - barLength;
        }
        double barL0Adj = 0.0;
        RectangleEdge barBase;
        if (orientation == PlotOrientation.HORIZONTAL) {
            if (positive && inverted || !positive && !inverted) {
                barL0Adj = barLengthAdj;
                barBase = RectangleEdge.RIGHT;
            }
            else {
                barBase = RectangleEdge.LEFT;
            }
        }
        else {
            if (positive && !inverted || !positive && inverted) {
                barL0Adj = barLengthAdj;
                barBase = RectangleEdge.BOTTOM;
            }
            else {
                barBase = RectangleEdge.TOP;
            }
        }

        // draw the bar...
        Rectangle2D bar = null;
        if (orientation == PlotOrientation.HORIZONTAL) {
            bar = new Rectangle2D.Double(barL0 - barL0Adj, barW0,
                    barLength + barLengthAdj, state.getBarWidth());
        }
        else {
            bar = new Rectangle2D.Double(barW0, barL0 - barL0Adj,
                    state.getBarWidth(), barLength + barLengthAdj);
        }
        if (getShadowsVisible()) {
            this.barPainter.paintBarShadow(g2, this, row, column, bar, barBase,
                true);