ringplot.java

关于jfreechart的电子说明书,一种说明图型使用的介绍

        notifyListeners(new PlotChangeEvent(this));
    }
    
    /**
     * Draws a single data item.
     *
     * @param g2  the graphics device (<code>null</code> not permitted).
     * @param section  the section index.
     * @param dataArea  the data plot area.
     * @param state  state information for one chart.
     * @param currentPass  the current pass index.
     */
    protected void drawItem(Graphics2D g2,
                            int section,
                            Rectangle2D dataArea,
                            PiePlotState state,
                            int currentPass) {
    
        PieDataset dataset = getDataset();
        Number n = dataset.getValue(section);
        if (n == null) {
            return;   
        }
        double value = n.doubleValue();
        double angle1 = 0.0;
        double angle2 = 0.0;
        
        Rotation direction = getDirection();
        if (direction == Rotation.CLOCKWISE) {
            angle1 = state.getLatestAngle();
            angle2 = angle1 - value / state.getTotal() * 360.0;
        }
        else if (direction == Rotation.ANTICLOCKWISE) {
            angle1 = state.getLatestAngle();
            angle2 = angle1 + value / state.getTotal() * 360.0;         
        }
        else {
            throw new IllegalStateException("Rotation type not recognised.");   
        }
        
        double angle = (angle2 - angle1);
        if (Math.abs(angle) > getMinimumArcAngleToDraw()) {
            double ep = 0.0;
            double mep = getMaximumExplodePercent();
            if (mep > 0.0) {
                ep = getExplodePercent(section) / mep;                
            }
            Rectangle2D arcBounds = getArcBounds(
                state.getPieArea(), state.getExplodedPieArea(),
                angle1, angle, ep
            );            
            Arc2D.Double arc = new Arc2D.Double(
                arcBounds, angle1, angle, Arc2D.OPEN
            );

            // create the bounds for the inner arc
            RectangleInsets s = new RectangleInsets(
                UnitType.RELATIVE, 0.10, 0.10, 0.10, 0.10
            );
            Rectangle2D innerArcBounds = new Rectangle2D.Double();
            innerArcBounds.setRect(arcBounds);
            s.trim(innerArcBounds);
            // calculate inner arc in reverse direction, for later 
            // GeneralPath construction
            Arc2D.Double arc2 = new Arc2D.Double(
                innerArcBounds, angle1 + angle, -angle, Arc2D.OPEN
            );
            GeneralPath path = new GeneralPath();
            path.moveTo(
                (float) arc.getStartPoint().getX(), 
                (float) arc.getStartPoint().getY()
            );
            path.append(arc.getPathIterator(null), false);
            path.append(arc2.getPathIterator(null), true);
            path.closePath();
            
            Line2D separator = new Line2D.Double(
                arc2.getEndPoint(), arc.getStartPoint()
            );
            
            if (currentPass == 0) {
                Paint shadowPaint = getShadowPaint();
                double shadowXOffset = getShadowXOffset();
                double shadowYOffset = getShadowYOffset();
                if (shadowPaint != null) {
                    Shape shadowArc = ShapeUtilities.createTranslatedShape(
                        path, (float) shadowXOffset, (float) shadowYOffset
                    );
                    g2.setPaint(shadowPaint);
                    g2.fill(shadowArc);
                }
            }
            else if (currentPass == 1) {

                Paint paint = getSectionPaint(section);
                g2.setPaint(paint);
                g2.fill(path);
                Paint outlinePaint = getSectionOutlinePaint(section);
                Stroke outlineStroke = getSectionOutlineStroke(section);
                if (outlinePaint != null && outlineStroke != null) {
                    g2.setPaint(outlinePaint);
                    g2.setStroke(outlineStroke);
                    g2.draw(path);
                }
                
                if (this.separatorsVisible) {
                    Line2D extendedSeparator = extendLine(
                        separator, this.innerSeparatorExtension, 
                        this.innerSeparatorExtension
                    );  
                    g2.setStroke(this.separatorStroke);
                    g2.setPaint(this.separatorPaint);
                    g2.draw(extendedSeparator);
                }
                
                // add an entity for the pie section
                if (state.getInfo() != null) {
                    EntityCollection entities = state.getEntityCollection();
                    if (entities != null) {
                        Comparable key = dataset.getKey(section);
                        String tip = null;
                        PieToolTipGenerator toolTipGenerator 
                            = getToolTipGenerator();
                        if (toolTipGenerator != null) {
                            tip = toolTipGenerator.generateToolTip(
                                dataset, key
                            );
                        }
                        String url = null;
                        PieURLGenerator urlGenerator = getURLGenerator();
                        if (urlGenerator != null) {
                            url = urlGenerator.generateURL(
                                dataset, key, getPieIndex()
                            );
                        }
                        PieSectionEntity entity = new PieSectionEntity(
                            path, dataset, getPieIndex(), section, key, tip, url
                        );
                        entities.add(entity);
                    }
                }
            }
        }    
        state.setLatestAngle(angle2);
    }

    /**
     * Tests this plot for equality with an arbitrary object.
     * 
     * @param obj  the object to test against (<code>null</code> permitted).
     * 
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (!(obj instanceof RingPlot)) {
            return false;
        }
        if (!super.equals(obj)) {
            return false;
        }
        RingPlot that = (RingPlot) obj;
        if (this.separatorsVisible != that.separatorsVisible) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.separatorStroke, that.separatorStroke
        )) {
            return false;
        }
        if (!PaintUtilities.equal(this.separatorPaint, that.separatorPaint)) {
            return false;
        }
        if (this.innerSeparatorExtension != that.innerSeparatorExtension) {
            return false;
        }
        if (this.outerSeparatorExtension != that.outerSeparatorExtension) {
            return false;
        }        
        return true;
    }
    
    /**
     * Creates a new line by extending an existing line.
     * 
     * @param line  the line (<code>null</code> not permitted).
     * @param startPercent  the amount to extend the line at the start point 
     *                      end.
     * @param endPercent  the amount to extend the line at the end point end.
     * 
     * @return A new line.
     */
    private Line2D extendLine(Line2D line, double startPercent, 
                              double endPercent) {
        if (line == null) {
            throw new IllegalArgumentException("Null 'line' argument.");
        }
        double x1 = line.getX1();
        double x2 = line.getX2();
        double deltaX = x2 - x1;
        double y1 = line.getY1();
        double y2 = line.getY2();
        double deltaY = y2 - y1;
        x1 = x1 - (startPercent * deltaX);
        y1 = y1 - (startPercent * deltaY);
        x2 = x2 + (endPercent * deltaX);
        y2 = y2 + (endPercent * deltaY);
        return new Line2D.Double(x1, y1, x2, y2);
    }
    
    /**
     * 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.writeStroke(this.separatorStroke, stream);
        SerialUtilities.writePaint(this.separatorPaint, stream);
    }

    /**
     * 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.separatorStroke = SerialUtilities.readStroke(stream);
        this.separatorPaint = SerialUtilities.readPaint(stream);
    }
    
}