jfreechart example source code file (XYStepAreaRenderer.java)

This example jfreechart source code file (XYStepAreaRenderer.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

area, area_and_shapes, awt, geometry, io, plotrenderinginfo, rectangle2d, rectangle2d, shapes, valueaxis, xydataset, xyitemrendererstate, xyitemrendererstate, xyplot, xyplot, xysteparearenderer, xysteparearenderer

The jfreechart XYStepAreaRenderer.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * -----------------------
 * XYStepAreaRenderer.java
 * -----------------------
 * (C) Copyright 2003-2008, by Matthias Rose and Contributors.
 *
 * Original Author:  Matthias Rose (based on XYAreaRenderer.java);
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * Changes:
 * --------
 * 07-Oct-2003 : Version 1, contributed by Matthias Rose (DG);
 * 10-Feb-2004 : Added some getter and setter methods (DG);
 * 25-Feb-2004 : Replaced CrosshairInfo with CrosshairState.  Renamed
 *               XYToolTipGenerator --> XYItemLabelGenerator (DG);
 * 15-Jul-2004 : Switched getX() with getXValue() and getY() with
 *               getYValue() (DG);
 * 11-Nov-2004 : Now uses ShapeUtilities to translate shapes (DG);
 * 06-Jul-2005 : Renamed get/setPlotShapes() --> get/setShapesVisible() (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 06-Jul-2006 : Modified to call dataset methods that return double
 *               primitives only (DG);
 * 06-Feb-2007 : Fixed bug 1086307, crosshairs with multiple axes (DG);
 * 14-Feb-2007 : Added equals() method override (DG);
 * 04-May-2007 : Set processVisibleItemsOnly flag to false (DG);
 * 14-May-2008 : Call addEntity() from within drawItem() (DG);
 *
 */

package org.jfree.chart.renderer.xy;

import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Polygon;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.labels.XYToolTipGenerator;
import org.jfree.chart.plot.CrosshairState;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.urls.XYURLGenerator;
import org.jfree.data.xy.XYDataset;
import org.jfree.util.PublicCloneable;
import org.jfree.util.ShapeUtilities;

/**
 * A step chart renderer that fills the area between the step and the x-axis.
 * The example shown here is generated by the
 * <code>XYStepAreaRendererDemo1.java program included in the JFreeChart
 * demo collection:
 * <br>

 * <img src="../../../../../images/XYStepAreaRendererSample.png"
 * alt="XYStepAreaRendererSample.png" />
 */
public class XYStepAreaRenderer extends AbstractXYItemRenderer
        implements XYItemRenderer, Cloneable, PublicCloneable, Serializable {

    /** For serialization. */
    private static final long serialVersionUID = -7311560779702649635L;

    /** Useful constant for specifying the type of rendering (shapes only). */
    public static final int SHAPES = 1;

    /** Useful constant for specifying the type of rendering (area only). */
    public static final int AREA = 2;

    /**
     * Useful constant for specifying the type of rendering (area and shapes).
     */
    public static final int AREA_AND_SHAPES = 3;

    /** A flag indicating whether or not shapes are drawn at each XY point. */
    private boolean shapesVisible;

    /** A flag that controls whether or not shapes are filled for ALL series. */
    private boolean shapesFilled;

    /** A flag indicating whether or not Area are drawn at each XY point. */
    private boolean plotArea;

    /** A flag that controls whether or not the outline is shown. */
    private boolean showOutline;

    /** Area of the complete series */
    protected transient Polygon pArea = null;

    /**
     * The value on the range axis which defines the 'lower' border of the
     * area.
     */
    private double rangeBase;

    /**
     * Constructs a new renderer.
     */
    public XYStepAreaRenderer() {
        this(AREA);
    }

    /**
     * Constructs a new renderer.
     *
     * @param type  the type of the renderer.
     */
    public XYStepAreaRenderer(int type) {
        this(type, null, null);
    }

    /**
     * Constructs a new renderer.
     * <p>
     * To specify the type of renderer, use one of the constants:
     * AREA, SHAPES or AREA_AND_SHAPES.
     *
     * @param type  the type of renderer.
     * @param toolTipGenerator  the tool tip generator to use
     *                          (<code>null permitted).
     * @param urlGenerator  the URL generator (<code>null permitted).
     */
    public XYStepAreaRenderer(int type,
                              XYToolTipGenerator toolTipGenerator,
                              XYURLGenerator urlGenerator) {

        super();
        setBaseToolTipGenerator(toolTipGenerator);
        setURLGenerator(urlGenerator);

        if (type == AREA) {
            this.plotArea = true;
        }
        else if (type == SHAPES) {
            this.shapesVisible = true;
        }
        else if (type == AREA_AND_SHAPES) {
            this.plotArea = true;
            this.shapesVisible = true;
        }
        this.showOutline = false;
    }

    /**
     * Returns a flag that controls whether or not outlines of the areas are
     * drawn.
     *
     * @return The flag.
     *
     * @see #setOutline(boolean)
     */
    public boolean isOutline() {
        return this.showOutline;
    }

    /**
     * Sets a flag that controls whether or not outlines of the areas are
     * drawn, and sends a {@link RendererChangeEvent} to all registered
     * listeners.
     *
     * @param show  the flag.
     *
     * @see #isOutline()
     */
    public void setOutline(boolean show) {
        this.showOutline = show;
        fireChangeEvent();
    }

    /**
     * Returns true if shapes are being plotted by the renderer.
     *
     * @return <code>true if shapes are being plotted by the renderer.
     *
     * @see #setShapesVisible(boolean)
     */
    public boolean getShapesVisible() {
        return this.shapesVisible;
    }

    /**
     * Sets the flag that controls whether or not shapes are displayed for each
     * data item, and sends a {@link RendererChangeEvent} to all registered
     * listeners.
     *
     * @param flag  the flag.
     *
     * @see #getShapesVisible()
     */
    public void setShapesVisible(boolean flag) {
        this.shapesVisible = flag;
        fireChangeEvent();
    }

    /**
     * Returns the flag that controls whether or not the shapes are filled.
     *
     * @return A boolean.
     *
     * @see #setShapesFilled(boolean)
     */
    public boolean isShapesFilled() {
        return this.shapesFilled;
    }

    /**
     * Sets the 'shapes filled' for ALL series and sends a
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param filled  the flag.
     *
     * @see #isShapesFilled()
     */
    public void setShapesFilled(boolean filled) {
        this.shapesFilled = filled;
        fireChangeEvent();
    }

    /**
     * Returns true if Area is being plotted by the renderer.
     *
     * @return <code>true if Area is being plotted by the renderer.
     *
     * @see #setPlotArea(boolean)
     */
    public boolean getPlotArea() {
        return this.plotArea;
    }

    /**
     * Sets a flag that controls whether or not areas are drawn for each data
     * item and sends a {@link RendererChangeEvent} to all registered
     * listeners.
     *
     * @param flag  the flag.
     *
     * @see #getPlotArea()
     */
    public void setPlotArea(boolean flag) {
        this.plotArea = flag;
        fireChangeEvent();
    }

    /**
     * Returns the value on the range axis which defines the 'lower' border of
     * the area.
     *
     * @return <code>double the value on the range axis which defines
     *         the 'lower' border of the area.
     *
     * @see #setRangeBase(double)
     */
    public double getRangeBase() {
        return this.rangeBase;
    }

    /**
     * Sets the value on the range axis which defines the default border of the
     * area, and sends a {@link RendererChangeEvent} to all registered
     * listeners.  E.g. setRangeBase(Double.NEGATIVE_INFINITY) lets areas always
     * reach the lower border of the plotArea.
     *
     * @param val  the value on the range axis which defines the default border
     *             of the area.
     *
     * @see #getRangeBase()
     */
    public void setRangeBase(double val) {
        this.rangeBase = val;
        fireChangeEvent();
    }

    /**
     * Initialises the renderer.  Here we calculate the Java2D y-coordinate for
     * zero, since all the bars have their bases fixed at zero.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area inside the axes.
     * @param plot  the plot.
     * @param data  the data.
     * @param info  an optional info collection object to return data back to
     *              the caller.
     *
     * @return The number of passes required by the renderer.
     */
    public XYItemRendererState initialise(Graphics2D g2,
                                          Rectangle2D dataArea,
                                          XYPlot plot,
                                          XYDataset data,
                                          PlotRenderingInfo info) {


        XYItemRendererState state = super.initialise(g2, dataArea, plot, data,
                info);
        // disable visible items optimisation - it doesn't work for this
        // renderer...
        state.setProcessVisibleItemsOnly(false);
        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 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) {

        PlotOrientation orientation = plot.getOrientation();

        // Get the item count for the series, so that we can know which is the
        // end of the series.
        int itemCount = dataset.getItemCount(series);

        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);
        double x = x1;
        double y = Double.isNaN(y1) ? getRangeBase() : y1;
        double transX1 = domainAxis.valueToJava2D(x, dataArea,
                plot.getDomainAxisEdge());
        double transY1 = rangeAxis.valueToJava2D(y, dataArea,
                plot.getRangeAxisEdge());

        // avoid possible sun.dc.pr.PRException: endPath: bad path
        transY1 = restrictValueToDataArea(transY1, plot, dataArea);

        if (this.pArea == null && !Double.isNaN(y1)) {

            // Create a new Area for the series
            this.pArea = new Polygon();

            // start from Y = rangeBase
            double transY2 = rangeAxis.valueToJava2D(getRangeBase(), dataArea,
                    plot.getRangeAxisEdge());

            // avoid possible sun.dc.pr.PRException: endPath: bad path
            transY2 = restrictValueToDataArea(transY2, plot, dataArea);

            // The first point is (x, this.baseYValue)
            if (orientation == PlotOrientation.VERTICAL) {
                this.pArea.addPoint((int) transX1, (int) transY2);
            }
            else if (orientation == PlotOrientation.HORIZONTAL) {
                this.pArea.addPoint((int) transY2, (int) transX1);
            }
        }

        double transX0 = 0;
        double transY0 = restrictValueToDataArea(getRangeBase(), plot,
                dataArea);

        double x0;
        double y0;
        if (item > 0) {
            // get the previous data point...
            x0 = dataset.getXValue(series, item - 1);
            y0 = Double.isNaN(y1) ? y1 : dataset.getYValue(series, item - 1);

            x = x0;
            y = Double.isNaN(y0) ? getRangeBase() : y0;
            transX0 = domainAxis.valueToJava2D(x, dataArea,
                    plot.getDomainAxisEdge());
            transY0 = rangeAxis.valueToJava2D(y, dataArea,
                    plot.getRangeAxisEdge());

            // avoid possible sun.dc.pr.PRException: endPath: bad path
            transY0 = restrictValueToDataArea(transY0, plot, dataArea);

            if (Double.isNaN(y1)) {
                // NULL value -> insert point on base line
                // instead of 'step point'
                transX1 = transX0;
                transY0 = transY1;
            }
            if (transY0 != transY1) {
                // not just a horizontal bar but need to perform a 'step'.
                if (orientation == PlotOrientation.VERTICAL) {
                    this.pArea.addPoint((int) transX1, (int) transY0);
                }
                else if (orientation == PlotOrientation.HORIZONTAL) {
                    this.pArea.addPoint((int) transY0, (int) transX1);
                }
            }
        }

        Shape shape = null;
        if (!Double.isNaN(y1)) {
            // Add each point to Area (x, y)
            if (orientation == PlotOrientation.VERTICAL) {
                this.pArea.addPoint((int) transX1, (int) transY1);
            }
            else if (orientation == PlotOrientation.HORIZONTAL) {
                this.pArea.addPoint((int) transY1, (int) transX1);
            }

            if (getShapesVisible()) {
                shape = getItemShape(series, item);
                if (orientation == PlotOrientation.VERTICAL) {
                    shape = ShapeUtilities.createTranslatedShape(shape,
                            transX1, transY1);
                }
                else if (orientation == PlotOrientation.HORIZONTAL) {
                    shape = ShapeUtilities.createTranslatedShape(shape,
                            transY1, transX1);
                }
                if (isShapesFilled()) {
                    g2.fill(shape);
                }
                else {
                    g2.draw(shape);
                }
            }
            else {
                if (orientation == PlotOrientation.VERTICAL) {
                    shape = new Rectangle2D.Double(transX1 - 2, transY1 - 2,
                            4.0, 4.0);
                }
                else if (orientation == PlotOrientation.HORIZONTAL) {
                    shape = new Rectangle2D.Double(transY1 - 2, transX1 - 2,
                            4.0, 4.0);
                }
            }
        }

        // Check if the item is the last item for the series or if it
        // is a NULL value and number of items > 0.  We can't draw an area for
        // a single point.
        if (getPlotArea() && item > 0 && this.pArea != null
                          && (item == (itemCount - 1) || Double.isNaN(y1))) {

            double transY2 = rangeAxis.valueToJava2D(getRangeBase(), dataArea,
                    plot.getRangeAxisEdge());

            // avoid possible sun.dc.pr.PRException: endPath: bad path
            transY2 = restrictValueToDataArea(transY2, plot, dataArea);

            if (orientation == PlotOrientation.VERTICAL) {
                // Add the last point (x,0)
                this.pArea.addPoint((int) transX1, (int) transY2);
            }
            else if (orientation == PlotOrientation.HORIZONTAL) {
                // Add the last point (x,0)
                this.pArea.addPoint((int) transY2, (int) transX1);
            }

            // fill the polygon
            g2.fill(this.pArea);

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

            // start new area when needed (see above)
            this.pArea = null;
        }

        // do we need to update the crosshair values?
        if (!Double.isNaN(y1)) {
            int domainAxisIndex = plot.getDomainAxisIndex(domainAxis);
            int rangeAxisIndex = plot.getRangeAxisIndex(rangeAxis);
            updateCrosshairValues(crosshairState, x1, y1, domainAxisIndex,
                    rangeAxisIndex, transX1, transY1, orientation);
        }

        // collect entity and tool tip information...
        EntityCollection entities = state.getEntityCollection();
        if (entities != null) {
            addEntity(entities, shape, dataset, series, item, transX1, transY1);
        }
    }

    /**
     * Tests this renderer for equality with an arbitrary object.
     *
     * @param obj  the object (<code>null permitted).
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof XYStepAreaRenderer)) {
            return false;
        }
        XYStepAreaRenderer that = (XYStepAreaRenderer) obj;
        if (this.showOutline != that.showOutline) {
            return false;
        }
        if (this.shapesVisible != that.shapesVisible) {
            return false;
        }
        if (this.shapesFilled != that.shapesFilled) {
            return false;
        }
        if (this.plotArea != that.plotArea) {
            return false;
        }
        if (this.rangeBase != that.rangeBase) {
            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 {
        return super.clone();
    }

    /**
     * Helper method which returns a value if it lies
     * inside the visible dataArea and otherwise the corresponding
     * coordinate on the border of the dataArea. The PlotOrientation
     * is taken into account.
     * Useful to avoid possible sun.dc.pr.PRException: endPath: bad path
     * which occurs when trying to draw lines/shapes which in large part
     * lie outside of the visible dataArea.
     *
     * @param value the value which shall be
     * @param dataArea  the area within which the data is being drawn.
     * @param plot  the plot (can be used to obtain standard color
     *              information etc).
     * @return <code>double value inside the data area.
     */
    protected static double restrictValueToDataArea(double value,
                                                    XYPlot plot,
                                                    Rectangle2D dataArea) {
        double min = 0;
        double max = 0;
        if (plot.getOrientation() == PlotOrientation.VERTICAL) {
            min = dataArea.getMinY();
            max = dataArea.getMaxY();
        }
        else if (plot.getOrientation() ==  PlotOrientation.HORIZONTAL) {
            min = dataArea.getMinX();
            max = dataArea.getMaxX();
        }
        if (value < min) {
            value = min;
        }
        else if (value > max) {
            value = max;
        }
        return value;
    }

}