axis.java

来自「JfreeChart 常用图表例子」· Java 代码 · 共 1,201 行 · 第 1/3 页

     * Calculates the positions of the ticks for the axis, storing the results
     * in the tick list (ready for drawing).
     *
     * @param g2  the graphics device.
     * @param state  the axis state.
     * @param dataArea  the area inside the axes.
     * @param edge  the edge on which the axis is located.
     * 
     * @return The list of ticks.
     */
    public abstract List refreshTicks(Graphics2D g2, 
                                      AxisState state,
                                      Rectangle2D dataArea,
                                      RectangleEdge edge);

    /**
     * Registers an object for notification of changes to the axis.
     *
     * @param listener  the object that is being registered.
     */
    public void addChangeListener(AxisChangeListener listener) {
        this.listenerList.add(AxisChangeListener.class, listener);
    }

    /**
     * Deregisters an object for notification of changes to the axis.
     *
     * @param listener  the object to deregister.
     */
    public void removeChangeListener(AxisChangeListener listener) {
        this.listenerList.remove(AxisChangeListener.class, listener);
    }

    /**
     * Returns <code>true</code> if the specified object is registered with
     * the dataset as a listener.  Most applications won't need to call this 
     * method, it exists mainly for use by unit testing code.
     * 
     * @param listener  the listener.
     * 
     * @return A boolean.
     */
    public boolean hasListener(EventListener listener) {
        List list = Arrays.asList(this.listenerList.getListenerList());
        return list.contains(listener);
    }
    
    /**
     * Notifies all registered listeners that the axis has changed.
     * The AxisChangeEvent provides information about the change.
     *
     * @param event  information about the change to the axis.
     */
    protected void notifyListeners(AxisChangeEvent event) {

        Object[] listeners = this.listenerList.getListenerList();
        for (int i = listeners.length - 2; i >= 0; i -= 2) {
            if (listeners[i] == AxisChangeListener.class) {
                ((AxisChangeListener) listeners[i + 1]).axisChanged(event);
            }
        }

    }

    /**
     * Returns a rectangle that encloses the axis label.  This is typically 
     * used for layout purposes (it gives the maximum dimensions of the label).
     *
     * @param g2  the graphics device.
     * @param edge  the edge of the plot area along which the axis is measuring.
     *
     * @return The enclosing rectangle.
     */
    protected Rectangle2D getLabelEnclosure(Graphics2D g2, RectangleEdge edge) {

        Rectangle2D result = new Rectangle2D.Double();
        String axisLabel = getLabel();
        if (axisLabel != null && !axisLabel.equals("")) {
            FontMetrics fm = g2.getFontMetrics(getLabelFont());
            Rectangle2D bounds = TextUtilities.getTextBounds(axisLabel, g2, fm);
            RectangleInsets insets = getLabelInsets();
            bounds = insets.createOutsetRectangle(bounds);
            double angle = getLabelAngle();
            if (edge == RectangleEdge.LEFT || edge == RectangleEdge.RIGHT) {
                angle = angle - Math.PI / 2.0;
            }
            double x = bounds.getCenterX();
            double y = bounds.getCenterY();
            AffineTransform transformer 
                = AffineTransform.getRotateInstance(angle, x, y);
            Shape labelBounds = transformer.createTransformedShape(bounds);
            result = labelBounds.getBounds2D();
        }

        return result;

    }

    /**
     * Draws the axis label.
     *
     * @param label  the label text.
     * @param g2  the graphics device.
     * @param plotArea  the plot area.
     * @param dataArea  the area inside the axes.
     * @param edge  the location of the axis.
     * @param state  the axis state (<code>null</code> not permitted).
     *
     * @return Information about the axis.
     */
    protected AxisState drawLabel(String label,
                                  Graphics2D g2, 
                                  Rectangle2D plotArea, 
                                  Rectangle2D dataArea,
                                  RectangleEdge edge, 
                                  AxisState state) {

        // it is unlikely that 'state' will be null, but check anyway...
        if (state == null) {
            throw new IllegalArgumentException("Null 'state' argument.");
        }
        
        if ((label == null) || (label.equals(""))) {
            return state;
        }

        Font font = getLabelFont();
        RectangleInsets insets = getLabelInsets();
        g2.setFont(font);
        g2.setPaint(getLabelPaint());
        FontMetrics fm = g2.getFontMetrics();
        Rectangle2D labelBounds = TextUtilities.getTextBounds(label, g2, fm);

        if (edge == RectangleEdge.TOP) {

            AffineTransform t = AffineTransform.getRotateInstance(
                getLabelAngle(), 
                labelBounds.getCenterX(), labelBounds.getCenterY()
            );
            Shape rotatedLabelBounds = t.createTransformedShape(labelBounds);
            labelBounds = rotatedLabelBounds.getBounds2D();
            double labelx = dataArea.getCenterX();
            double labely = state.getCursor() 
                            - insets.getBottom() 
                            - labelBounds.getHeight() / 2.0;
            TextUtilities.drawRotatedString(
                label, g2, (float) labelx, (float) labely,
                TextAnchor.CENTER, getLabelAngle(), TextAnchor.CENTER
            );
            state.cursorUp(
                insets.getTop() + labelBounds.getHeight() + insets.getBottom()
            );

        }
        else if (edge == RectangleEdge.BOTTOM) {

            AffineTransform t = AffineTransform.getRotateInstance(
                getLabelAngle(), 
                labelBounds.getCenterX(), labelBounds.getCenterY()
            );
            Shape rotatedLabelBounds = t.createTransformedShape(labelBounds);
            labelBounds = rotatedLabelBounds.getBounds2D();
            double labelx = dataArea.getCenterX();
            double labely = state.getCursor() 
                            + insets.getTop() + labelBounds.getHeight() / 2.0;
            TextUtilities.drawRotatedString(
                label, g2, (float) labelx, (float) labely,
                TextAnchor.CENTER, getLabelAngle(), TextAnchor.CENTER
            );
            state.cursorDown(
                insets.getTop() + labelBounds.getHeight() + insets.getBottom()
            );

        }
        else if (edge == RectangleEdge.LEFT) {

            AffineTransform t = AffineTransform.getRotateInstance(
                getLabelAngle() - Math.PI / 2.0,
                labelBounds.getCenterX(), labelBounds.getCenterY()
            );
            Shape rotatedLabelBounds = t.createTransformedShape(labelBounds);
            labelBounds = rotatedLabelBounds.getBounds2D();
            double labelx = state.getCursor() 
                            - insets.getRight() - labelBounds.getWidth() / 2.0;
            double labely = dataArea.getCenterY();
            TextUtilities.drawRotatedString(
                label, g2, (float) labelx, (float) labely, TextAnchor.CENTER, 
                getLabelAngle() - Math.PI / 2.0, TextAnchor.CENTER
            );
            state.cursorLeft(
                insets.getLeft() + labelBounds.getWidth() + insets.getRight()
            );
        }
        else if (edge == RectangleEdge.RIGHT) {

            AffineTransform t = AffineTransform.getRotateInstance(
                getLabelAngle() + Math.PI / 2.0, 
                labelBounds.getCenterX(), labelBounds.getCenterY()
            );
            Shape rotatedLabelBounds = t.createTransformedShape(labelBounds);
            labelBounds = rotatedLabelBounds.getBounds2D();
            double labelx = state.getCursor() 
                            + insets.getLeft() + labelBounds.getWidth() / 2.0;
            double labely = dataArea.getY() + dataArea.getHeight() / 2.0;
            TextUtilities.drawRotatedString(
                label, g2, (float) labelx, (float) labely, TextAnchor.CENTER,
                getLabelAngle() + Math.PI / 2.0, TextAnchor.CENTER
            );
            state.cursorRight(
                insets.getLeft() + labelBounds.getWidth() + insets.getRight()
            );

        }

        return state;

    }

    /**
     * Draws an axis line at the current cursor position and edge.
     * 
     * @param g2  the graphics device.
     * @param cursor  the cursor position.
     * @param dataArea  the data area.
     * @param edge  the edge.
     */
    protected void drawAxisLine(Graphics2D g2, double cursor,
            Rectangle2D dataArea, RectangleEdge edge) {
        
        Line2D axisLine = null;
        if (edge == RectangleEdge.TOP) {
            axisLine = new Line2D.Double(
                dataArea.getX(), cursor, dataArea.getMaxX(), cursor
            );  
        }
        else if (edge == RectangleEdge.BOTTOM) {
            axisLine = new Line2D.Double(
                dataArea.getX(), cursor, dataArea.getMaxX(), cursor
            );  
        }
        else if (edge == RectangleEdge.LEFT) {
            axisLine = new Line2D.Double(
                cursor, dataArea.getY(), cursor, dataArea.getMaxY()
            );  
        }
        else if (edge == RectangleEdge.RIGHT) {
            axisLine = new Line2D.Double(
                cursor, dataArea.getY(), cursor, dataArea.getMaxY()
            );  
        }
        g2.setPaint(this.axisLinePaint);
        g2.setStroke(this.axisLineStroke);
        g2.draw(axisLine);
        
    }

    /**
     * Returns a clone of the axis.
     * 
     * @return A clone.
     * 
     * @throws CloneNotSupportedException if some component of the axis does 
     *         not support cloning.
     */
    public Object clone() throws CloneNotSupportedException {
        Axis clone = (Axis) super.clone();
        // It's up to the plot which clones up to restore the correct references
        clone.plot = null;        
        clone.listenerList = new EventListenerList();
        return clone;
    }
    
    /**
     * Tests this axis for equality with another object.
     *
     * @param obj  the object (<code>null</code> permitted).
     *
     * @return <code>true</code> or <code>false</code>.
     */
    public boolean equals(Object obj) {

        if (obj == this) {
            return true;
        }

        if (!(obj instanceof Axis)) {
            return false;
        }
        Axis that = (Axis) obj;

        if (this.visible != that.visible) {
            return false;
        }

        if (!ObjectUtilities.equal(this.label, that.label)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.labelFont, that.labelFont)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.labelPaint, that.labelPaint)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.labelInsets, that.labelInsets)) {
            return false;
        }
        if (this.labelAngle != that.labelAngle) {
            return false;
        }
  
        if (this.axisLineVisible != that.axisLineVisible) {
            return false;
        }
        if (!ObjectUtilities.equal(this.axisLineStroke, that.axisLineStroke)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.axisLinePaint, that.axisLinePaint)) {
            return false;
        }
         
        if (this.tickLabelsVisible != that.tickLabelsVisible) {
            return false;
        }
        if (!ObjectUtilities.equal(this.tickLabelFont, that.tickLabelFont)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.tickLabelPaint, that.tickLabelPaint)) {
            return false;
        }
        if (!ObjectUtilities.equal(
            this.tickLabelInsets, that.tickLabelInsets
        )) {
            return false;
        }
        if (this.tickMarksVisible != that.tickMarksVisible) {
            return false;
        }
        if (this.tickMarkInsideLength != that.tickMarkInsideLength) {
            return false;
        }
                           
        if (this.tickMarkOutsideLength != that.tickMarkOutsideLength) {
            return false;
        }
                           
        if (!ObjectUtilities.equal(this.tickMarkPaint, that.tickMarkPaint)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.tickMarkStroke, that.tickMarkStroke)) {
            return false;
        }

        if (this.fixedDimension != that.fixedDimension) {
            return false;
        }

        return true;

    }

    /**
     * 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.writePaint(this.labelPaint, stream);
        SerialUtilities.writePaint(this.tickLabelPaint, stream);
        SerialUtilities.writeStroke(this.axisLineStroke, stream);
        SerialUtilities.writePaint(this.axisLinePaint, stream);
        SerialUtilities.writeStroke(this.tickMarkStroke, stream);
        SerialUtilities.writePaint(this.tickMarkPaint, 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.labelPaint = SerialUtilities.readPaint(stream);
        this.tickLabelPaint = SerialUtilities.readPaint(stream);
        this.axisLineStroke = SerialUtilities.readStroke(stream);
        this.axisLinePaint = SerialUtilities.readPaint(stream);
        this.tickMarkStroke = SerialUtilities.readStroke(stream);
        this.tickMarkPaint = SerialUtilities.readPaint(stream);
        this.listenerList = new EventListenerList();
    }

}