areaxyrenderer.java

这是一个segy数据显示程序

                                          XYDataset data,
                                          PlotRenderingInfo info) {
        AreaXYItemRendererState state = new AreaXYItemRendererState(info);
        return state;
    }

    /**
     * Draws the visual representation of a single data item.
     *
     * @param g2  the graphics device.
     * @param state  the renderer state.
     * @param dataArea  the area within which the data is being drawn.
     * @param info  collects information about the drawing.
     * @param plot  the plot (can be used to obtain standard color information etc).
     * @param domainAxis  the domain axis.
     * @param rangeAxis  the range axis.
     * @param dataset  the dataset.
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     * @param crosshairState  information about crosshairs on a plot.
     * @param pass  the pass index.
     */
    public void drawItem(Graphics2D g2,
                         XYItemRendererState state,
                         Rectangle2D dataArea,
                         PlotRenderingInfo info,
                         XYPlot plot,
                         ValueAxis domainAxis,
                         ValueAxis rangeAxis,
                         XYDataset dataset,
                         int series,
                         int item,
                         CrosshairState crosshairState,
                         int pass) {
        
        AreaXYItemRendererState areaState = (AreaXYItemRendererState) state;
        
        // get the data point...
        Number x1 = dataset.getXValue(series, item);
        Number y1 = dataset.getYValue(series, item);
        if (y1 == null) {
            y1 = AbstractRenderer.ZERO;
        }
        
        double transX1 = domainAxis.valueToJava2D(
            x1.doubleValue(), dataArea, plot.getDomainAxisEdge()
        );
        double transY1 = rangeAxis.valueToJava2D(
            y1.doubleValue(), dataArea, plot.getRangeAxisEdge()
        );
        
        // get the previous point and the next point so we can calculate a "hot spot"
        // for the area (used by the chart entity)...
        int itemCount = dataset.getItemCount(series);
        Number x0 = dataset.getXValue(series, Math.max(item - 1, 0));
        Number y0 = dataset.getYValue(series, Math.max(item - 1, 0));
        if (y0 == null) {
            y0 = AbstractRenderer.ZERO;
        }
        double transX0 = domainAxis.valueToJava2D(
            x0.doubleValue(), dataArea, plot.getDomainAxisEdge()
        );
        double transY0 = rangeAxis.valueToJava2D(
            y0.doubleValue(), dataArea, plot.getRangeAxisEdge()
        );
        
        Number x2 = dataset.getXValue(series, Math.min(item + 1, itemCount - 1));
        Number y2 = dataset.getYValue(series, Math.min(item + 1, itemCount - 1));
        if (y2 == null) {
            y2 = AbstractRenderer.ZERO;
        }
        double transX2 = domainAxis.valueToJava2D(
                x2.doubleValue(), dataArea, plot.getDomainAxisEdge()
        );
        double transY2 = rangeAxis.valueToJava2D(
                y2.doubleValue(), dataArea, plot.getRangeAxisEdge()
        );
        
        double transZero = rangeAxis.valueToJava2D(0.0, dataArea, plot.getRangeAxisEdge());
        Polygon hotspot = null;
        if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
            hotspot = new Polygon();
            hotspot.addPoint((int) transZero, (int) ((transX0 + transX1) / 2.0));
            hotspot.addPoint((int) ((transY0 + transY1) / 2.0), (int) ((transX0 + transX1) / 2.0));
            hotspot.addPoint((int) transY1, (int) transX1);
            hotspot.addPoint((int) ((transY1 + transY2) / 2.0), (int) ((transX1 + transX2) / 2.0));
            hotspot.addPoint((int) transZero, (int) ((transX1 + transX2) / 2.0));
        }
        else {  // vertical orientation
            hotspot = new Polygon();
            hotspot.addPoint((int) ((transX0 + transX1) / 2.0), (int) transZero);
            hotspot.addPoint((int) ((transX0 + transX1) / 2.0), (int) ((transY0 + transY1) / 2.0));
            hotspot.addPoint((int) transX1, (int) transY1);
            hotspot.addPoint((int) ((transX1 + transX2) / 2.0), (int) ((transY1 + transY2) / 2.0));
            hotspot.addPoint((int) ((transX1 + transX2) / 2.0), (int) transZero);
           }
        
        if (item == 0) {  // create a new area polygon for the series
            areaState.area = new Polygon();
            // the first point is (x, 0)
            double zero = rangeAxis.valueToJava2D(0.0, dataArea, plot.getRangeAxisEdge());
            if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                areaState.area.addPoint((int) transX1, (int) zero);
            }
            else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                areaState.area.addPoint((int) zero, (int) transX1);
            }
        }

        // Add each point to Area (x, y)
        if (plot.getOrientation() == PlotOrientation.VERTICAL) {
            areaState.area.addPoint((int) transX1, (int) transY1);
        }
        else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
            areaState.area.addPoint((int) transY1, (int) transX1);
        }
        
        Paint paint = getItemPaint(series, item);
        Stroke stroke = getItemStroke(series, item);
        g2.setPaint(paint);
        g2.setStroke(stroke);
        
        Shape shape = null;
        if (this.plotShapes) {
            shape = getItemShape(series, item);
            if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                shape = createTransformedShape(shape, transX1, transY1);
            }
            else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                shape = createTransformedShape(shape, transY1, transX1);
            }
            g2.draw(shape);
        }

        if (this.plotLines) {
            if (item > 0) {
                if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                    areaState.line.setLine(transX0, transY0, transX1, transY1);
                }
                else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                    areaState.line.setLine(transY0, transX0, transY1, transX1);
                }
                g2.draw(areaState.line);
            }
        }

        // Check if the item is the last item for the series.
        // and number of items > 0.  We can't draw an area for a single point.
        if (this.plotArea && item > 0 && item == (itemCount - 1)) {

            if (plot.getOrientation() == PlotOrientation.VERTICAL) {
                // Add the last point (x,0)
                areaState.area.addPoint((int) transX1, (int) transZero);
            }
            else if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
                // Add the last point (x,0)
                areaState.area.addPoint((int) transZero, (int) transX1);
            }

            g2.fill(areaState.area);

            // draw an outline around the Area.
            if (this.showOutline) {
                g2.setStroke(plot.getOutlineStroke());
                g2.setPaint(plot.getOutlinePaint());
                g2.draw(areaState.area);
            }
        }

        updateCrosshairValues(
            crosshairState, x1.doubleValue(), y1.doubleValue(), transX1, transY1, 
            plot.getOrientation()
        );

        // collect entity and tool tip information...
        if (state.getInfo() != null) {
            EntityCollection entities = state.getInfo().getOwner().getEntityCollection();
            if (entities != null && hotspot != null) {
                String tip = null;
                XYToolTipGenerator generator = getToolTipGenerator(series, item);
                if (generator != null) {
                    tip = generator.generateToolTip(dataset, series, item);
                }
                String url = null;
                if (getURLGenerator() != null) {
                    url = getURLGenerator().generateURL(dataset, series, item);
                }
                XYItemEntity entity = new XYItemEntity(hotspot, dataset, series, item, tip, url);
                entities.addEntity(entity);
            }
        }

    }

    /**
     * Returns a clone of the renderer.
     * 
     * @return A clone.
     * 
     * @throws CloneNotSupportedException  if the renderer cannot be cloned.
     */
    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }
    
}

/**
 * The state object used by the renderer for one chart drawing.  The state is set-up by the
 * initialise() method, and the plot will pass this state object to each invocation of the
 * drawItem(...) method.  At the end of drawing the chart, the state is discarded.
 * <p>
 * If a chart is being drawn to several targets simultaneously, a different state instance will 
 * be used for each drawing.
 */
class AreaXYItemRendererState extends XYItemRendererState {
    
    /** Working storage for the area under one series. */
    public Polygon area;
    
    /** Working line that can be recycled. */
    public Line2D line;
    
    /**
     * Creates a new state.
     * 
     * @param info  the plot rendering info.
     */
    public AreaXYItemRendererState(PlotRenderingInfo info) {
        super(info);
        this.area = new Polygon();
        this.line = new Line2D.Double();
    }
    
}