standardxyitemrenderer.java

java图形利器

        State state = new State(info);
        state.seriesPath = new GeneralPath();
        state.seriesIndex = -1;
        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  crosshair information for the plot 
     *                        (<code>null</code> permitted).
     * @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) {

        boolean itemVisible = getItemVisible(series, item);
        
        // setup for collecting optional entity info...
        Shape entityArea = null;
        EntityCollection entities = null;
        if (info != null) {
            entities = info.getOwner().getEntityCollection();
        }

        PlotOrientation orientation = plot.getOrientation();
        Paint paint = getItemPaint(series, item);
        Stroke seriesStroke = getItemStroke(series, item);
        g2.setPaint(paint);
        g2.setStroke(seriesStroke);

        // get the data point...
        double x1 = dataset.getXValue(series, item);
        double y1 = dataset.getYValue(series, item);
        if (Double.isNaN(x1) || Double.isNaN(y1)) {
            itemVisible = false;
        }

        RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
        RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
        double transX1 = domainAxis.valueToJava2D(x1, dataArea, xAxisLocation);
        double transY1 = rangeAxis.valueToJava2D(y1, dataArea, yAxisLocation);

        if (getPlotLines()) {
            if (this.drawSeriesLineAsPath) {
                State s = (State) state;
                if (s.getSeriesIndex() != series) {
                    // we are starting a new series path
                    s.seriesPath.reset();
                    s.lastPointGood = false;
                    s.setSeriesIndex(series);
                }
                
                // update path to reflect latest point
                if (itemVisible && !Double.isNaN(transX1) 
                        && !Double.isNaN(transY1)) {
                    float x = (float) transX1;
                    float y = (float) transY1;
                    if (orientation == PlotOrientation.HORIZONTAL) {
                        x = (float) transY1;
                        y = (float) transX1;
                    }
                    if (s.isLastPointGood()) {
                        // TODO: check threshold
                        s.seriesPath.lineTo(x, y);
                    }
                    else {
                        s.seriesPath.moveTo(x, y);
                    }
                    s.setLastPointGood(true);
                }
                else {
                    s.setLastPointGood(false);
                }
                if (item == dataset.getItemCount(series) - 1) {
                    if (s.seriesIndex == series) {
                        // draw path
                        g2.setStroke(lookupSeriesStroke(series));
                        g2.setPaint(lookupSeriesPaint(series));
                        g2.draw(s.seriesPath);
                    }
                }
            }

            else if (item != 0 && itemVisible) {
                // get the previous data point...
                double x0 = dataset.getXValue(series, item - 1);
                double y0 = dataset.getYValue(series, item - 1);
                if (!Double.isNaN(x0) && !Double.isNaN(y0)) {
                    boolean drawLine = true;
                    if (getPlotDiscontinuous()) {
                        // only draw a line if the gap between the current and 
                        // previous data point is within the threshold
                        int numX = dataset.getItemCount(series);
                        double minX = dataset.getXValue(series, 0);
                        double maxX = dataset.getXValue(series, numX - 1);
                        if (this.gapThresholdType == UnitType.ABSOLUTE) {
                            drawLine = Math.abs(x1 - x0) <= this.gapThreshold;
                        }
                        else {
                            drawLine = Math.abs(x1 - x0) <= ((maxX - minX) 
                                / numX * getGapThreshold());
                        }
                    }
                    if (drawLine) {
                        double transX0 = domainAxis.valueToJava2D(x0, dataArea,
                                xAxisLocation);
                        double transY0 = rangeAxis.valueToJava2D(y0, dataArea, 
                                yAxisLocation);

                        // only draw if we have good values
                        if (Double.isNaN(transX0) || Double.isNaN(transY0) 
                            || Double.isNaN(transX1) || Double.isNaN(transY1)) {
                            return;
                        }

                        if (orientation == PlotOrientation.HORIZONTAL) {
                            state.workingLine.setLine(transY0, transX0, 
                                    transY1, transX1);
                        }
                        else if (orientation == PlotOrientation.VERTICAL) {
                            state.workingLine.setLine(transX0, transY0, 
                                    transX1, transY1);
                        }

                        if (state.workingLine.intersects(dataArea)) {
                            g2.draw(state.workingLine);
                        }
                    }
                }
            }
        }
        
        // we needed to get this far even for invisible items, to ensure that
        // seriesPath updates happened, but now there is nothing more we need
        // to do for non-visible items...
        if (!itemVisible) {
            return;
        }

        if (getBaseShapesVisible()) {

            Shape shape = getItemShape(series, item);
            if (orientation == PlotOrientation.HORIZONTAL) {
                shape = ShapeUtilities.createTranslatedShape(shape, transY1, 
                        transX1);
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                shape = ShapeUtilities.createTranslatedShape(shape, transX1, 
                        transY1);
            }
            if (shape.intersects(dataArea)) {
                if (getItemShapeFilled(series, item)) {
                    g2.fill(shape);
                }
                else {
                    g2.draw(shape);
                }
            }
            entityArea = shape;

        }

        if (getPlotImages()) {
            Image image = getImage(plot, series, item, transX1, transY1);
            if (image != null) {
                Point hotspot = getImageHotspot(plot, series, item, transX1, 
                        transY1, image);
                g2.drawImage(image, (int) (transX1 - hotspot.getX()), 
                        (int) (transY1 - hotspot.getY()), null);
                entityArea = new Rectangle2D.Double(transX1 - hotspot.getX(), 
                        transY1 - hotspot.getY(), image.getWidth(null), 
                        image.getHeight(null));
            }

        }

        double xx = transX1;
        double yy = transY1;
        if (orientation == PlotOrientation.HORIZONTAL) {
            xx = transY1;
            yy = transX1;
        }          

        // draw the item label if there is one...
        if (isItemLabelVisible(series, item)) {
            drawItemLabel(g2, orientation, dataset, series, item, xx, yy, 
                    (y1 < 0.0));
        }

        int domainAxisIndex = plot.getDomainAxisIndex(domainAxis);
        int rangeAxisIndex = plot.getRangeAxisIndex(rangeAxis);
        updateCrosshairValues(crosshairState, x1, y1, domainAxisIndex, 
                rangeAxisIndex, transX1, transY1, orientation);

        // add an entity for the item...
        if (entities != null && dataArea.contains(xx, yy)) {
            addEntity(entities, entityArea, dataset, series, item, xx, yy);
        }

    }

    /**
     * Tests this renderer for equality with another object.
     *
     * @param obj  the object (<code>null</code> permitted).
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {

        if (obj == this) {
            return true;
        }
        if (!(obj instanceof StandardXYItemRenderer)) {
            return false;
        }
        StandardXYItemRenderer that = (StandardXYItemRenderer) obj;
        if (this.baseShapesVisible != that.baseShapesVisible) {
            return false;
        }
        if (this.plotLines != that.plotLines) {
            return false;
        }
        if (this.plotImages != that.plotImages) {
            return false;
        }
        if (this.plotDiscontinuous != that.plotDiscontinuous) {
            return false;
        }
        if (this.gapThresholdType != that.gapThresholdType) {
            return false;
        }
        if (this.gapThreshold != that.gapThreshold) {
            return false;
        }
        if (!ObjectUtilities.equal(this.shapesFilled, that.shapesFilled)) {
            return false;
        }
        if (!this.seriesShapesFilled.equals(that.seriesShapesFilled)) {
            return false;
        }
        if (this.baseShapesFilled != that.baseShapesFilled) {
            return false;
        }
        if (this.drawSeriesLineAsPath != that.drawSeriesLineAsPath) {
            return false;
        }
        if (!ShapeUtilities.equal(this.legendLine, that.legendLine)) {
            return false;   
        }
        return super.equals(obj);

    }

    /**
     * Returns a clone of the renderer.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException  if the renderer cannot be cloned.
     */
    public Object clone() throws CloneNotSupportedException {
        StandardXYItemRenderer clone = (StandardXYItemRenderer) super.clone();
        clone.seriesShapesFilled 
                = (BooleanList) this.seriesShapesFilled.clone();
        clone.legendLine = ShapeUtilities.clone(this.legendLine);
        return clone;
    }

    ////////////////////////////////////////////////////////////////////////////
    // PROTECTED METHODS
    // These provide the opportunity to subclass the standard renderer and 
    // create custom effects.
    ////////////////////////////////////////////////////////////////////////////

    /**
     * Returns the image used to draw a single data item.
     *
     * @param plot  the plot (can be used to obtain standard color information 
     *              etc).
     * @param series  the series index.
     * @param item  the item index.
     * @param x  the x value of the item.
     * @param y  the y value of the item.
     *
     * @return The image.
     * 
     * @see #getPlotImages()
     */
    protected Image getImage(Plot plot, int series, int item, 
                             double x, double y) {
        // this method must be overridden if you want to display images
        return null;
    }

    /**
     * Returns the hotspot of the image used to draw a single data item.
     * The hotspot is the point relative to the top left of the image
     * that should indicate the data item. The default is the center of the
     * image.
     *
     * @param plot  the plot (can be used to obtain standard color information 
     *              etc).
     * @param image  the image (can be used to get size information about the 
     *               image)
     * @param series  the series index
     * @param item  the item index
     * @param x  the x value of the item
     * @param y  the y value of the item
     *
     * @return The hotspot used to draw the data item.
     */
    protected Point getImageHotspot(Plot plot, int series, int item,
                                    double x, double y, Image image) {

        int height = image.getHeight(null);
        int width = image.getWidth(null);
        return new Point(width / 2, height / 2);

    }
    
    /**
     * Provides serialization support.
     *
     * @param stream  the input stream.
     *
     * @throws IOException  if there is an I/O error.
     * @throws ClassNotFoundException  if there is a classpath problem.
     */
    private void readObject(ObjectInputStream stream) 
            throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        this.legendLine = SerialUtilities.readShape(stream);
    }
    
    /**
     * Provides serialization support.
     *
     * @param stream  the output stream.
     *
     * @throws IOException  if there is an I/O error.
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        stream.defaultWriteObject();
        SerialUtilities.writeShape(this.legendLine, stream);
    }

}