jfreechart example source code file (AreaRenderer.java)

This example jfreechart source code file (AreaRenderer.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

arearenderer, arearenderer, arearendererendtype, awt, categorydataset, categoryplot, generalpath, geometry, io, legenditem, legenditem, number, number, paint, rectangleedge, string, string

The jfreechart AreaRenderer.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.]
 *
 * -----------------
 * AreaRenderer.java
 * -----------------
 * (C) Copyright 2002-2008, by Jon Iles and Contributors.
 *
 * Original Author:  Jon Iles;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *                   Christian W. Zuckschwerdt;
 *
 * Changes:
 * --------
 * 21-May-2002 : Version 1, contributed by John Iles (DG);
 * 29-May-2002 : Now extends AbstractCategoryItemRenderer (DG);
 * 11-Jun-2002 : Updated Javadoc comments (DG);
 * 25-Jun-2002 : Removed unnecessary imports (DG);
 * 01-Oct-2002 : Fixed errors reported by Checkstyle (DG);
 * 10-Oct-2002 : Added constructors and basic entity support (DG);
 * 24-Oct-2002 : Amendments for changes in CategoryDataset interface and
 *               CategoryToolTipGenerator interface (DG);
 * 05-Nov-2002 : Replaced references to CategoryDataset with TableDataset (DG);
 * 06-Nov-2002 : Renamed drawCategoryItem() --> drawItem() and now using axis
 *               for category spacing.  Renamed AreaCategoryItemRenderer
 *               --> AreaRenderer (DG);
 * 17-Jan-2003 : Moved plot classes into a separate package (DG);
 * 25-Mar-2003 : Implemented Serializable (DG);
 * 10-Apr-2003 : Changed CategoryDataset to KeyedValues2DDataset in
 *               drawItem() method (DG);
 * 12-May-2003 : Modified to take into account the plot orientation (DG);
 * 30-Jul-2003 : Modified entity constructor (CZ);
 * 13-Aug-2003 : Implemented Cloneable (DG);
 * 07-Oct-2003 : Added renderer state (DG);
 * 05-Nov-2004 : Modified drawItem() signature (DG);
 * 20-Apr-2005 : Apply tooltips and URLs to legend items (DG);
 * 09-Jun-2005 : Use addItemEntity() method from superclass (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 11-Oct-2006 : Fixed bug in equals() method (DG);
 * 30-Nov-2006 : Added checks for series visibility (DG);
 * 20-Apr-2007 : Updated getLegendItem() for renderer change (DG);
 * 17-May-2007 : Set datasetIndex and seriesIndex in getLegendItem() (DG);
 * 18-May-2007 : Set dataset and seriesKey for LegendItem (DG);
 * 17-Jun-2008 : Apply legend shape, font and paint attributes (DG);
 * 26-Jun-2008 : Added crosshair support (DG);
 *
 */

package org.jfree.chart.renderer.category;

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

import org.jfree.chart.LegendItem;
import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.renderer.AreaRendererEndType;
import org.jfree.data.category.CategoryDataset;
import org.jfree.ui.RectangleEdge;
import org.jfree.util.PublicCloneable;

/**
 * A category item renderer that draws area charts.  You can use this renderer
 * with the {@link CategoryPlot} class.  The example shown here is generated
 * by the <code>AreaChartDemo1.java program included in the JFreeChart
 * Demo Collection:
 * <br>

 * <img src="../../../../../images/AreaRendererSample.png"
 * alt="AreaRendererSample.png" />
 */
public class AreaRenderer extends AbstractCategoryItemRenderer
        implements Cloneable, PublicCloneable, Serializable {

    /** For serialization. */
    private static final long serialVersionUID = -4231878281385812757L;

    /** A flag that controls how the ends of the areas are drawn. */
    private AreaRendererEndType endType;

    /**
     * Creates a new renderer.
     */
    public AreaRenderer() {
        super();
        this.endType = AreaRendererEndType.TAPER;
        setBaseLegendShape(new Rectangle2D.Double(-4.0, -4.0, 8.0, 8.0));
    }

    /**
     * Returns a token that controls how the renderer draws the end points.
     * The default value is {@link AreaRendererEndType#TAPER}.
     *
     * @return The end type (never <code>null).
     *
     * @see #setEndType
     */
    public AreaRendererEndType getEndType() {
        return this.endType;
    }

    /**
     * Sets a token that controls how the renderer draws the end points, and
     * sends a {@link RendererChangeEvent} to all registered listeners.
     *
     * @param type  the end type (<code>null not permitted).
     *
     * @see #getEndType()
     */
    public void setEndType(AreaRendererEndType type) {
        if (type == null) {
            throw new IllegalArgumentException("Null 'type' argument.");
        }
        this.endType = type;
        fireChangeEvent();
    }

    /**
     * Returns a legend item for a series.
     *
     * @param datasetIndex  the dataset index (zero-based).
     * @param series  the series index (zero-based).
     *
     * @return The legend item.
     */
    public LegendItem getLegendItem(int datasetIndex, int series) {

        // if there is no plot, there is no dataset to access...
        CategoryPlot cp = getPlot();
        if (cp == null) {
            return null;
        }

        // check that a legend item needs to be displayed...
        if (!isSeriesVisible(series) || !isSeriesVisibleInLegend(series)) {
            return null;
        }

        CategoryDataset dataset = cp.getDataset(datasetIndex);
        String label = getLegendItemLabelGenerator().generateLabel(dataset,
                series);
        String description = label;
        String toolTipText = null;
        if (getLegendItemToolTipGenerator() != null) {
            toolTipText = getLegendItemToolTipGenerator().generateLabel(
                    dataset, series);
        }
        String urlText = null;
        if (getLegendItemURLGenerator() != null) {
            urlText = getLegendItemURLGenerator().generateLabel(dataset,
                    series);
        }
        Shape shape = lookupLegendShape(series);
        Paint paint = lookupSeriesPaint(series);
        Paint outlinePaint = lookupSeriesOutlinePaint(series);
        Stroke outlineStroke = lookupSeriesOutlineStroke(series);

        LegendItem result = new LegendItem(label, description, toolTipText,
                urlText, shape, paint, outlineStroke, outlinePaint);
        result.setLabelFont(lookupLegendTextFont(series));
        Paint labelPaint = lookupLegendTextPaint(series);
        if (labelPaint != null) {
            result.setLabelPaint(labelPaint);
        }
        result.setDataset(dataset);
        result.setDatasetIndex(datasetIndex);
        result.setSeriesKey(dataset.getRowKey(series));
        result.setSeriesIndex(series);
        return result;

    }

    /**
     * Draw a single data item.
     *
     * @param g2  the graphics device.
     * @param state  the renderer state.
     * @param dataArea  the data plot area.
     * @param plot  the plot.
     * @param domainAxis  the domain axis.
     * @param rangeAxis  the range axis.
     * @param dataset  the dataset.
     * @param row  the row index (zero-based).
     * @param column  the column index (zero-based).
     * @param pass  the pass index.
     */
    public void drawItem(Graphics2D g2,
                         CategoryItemRendererState state,
                         Rectangle2D dataArea,
                         CategoryPlot plot,
                         CategoryAxis domainAxis,
                         ValueAxis rangeAxis,
                         CategoryDataset dataset,
                         int row,
                         int column,
                         int pass) {

        // do nothing if item is not visible
        if (!getItemVisible(row, column)) {
            return;
        }

        // plot non-null values only...
        Number value = dataset.getValue(row, column);
        if (value != null) {
            PlotOrientation orientation = plot.getOrientation();
            RectangleEdge axisEdge = plot.getDomainAxisEdge();
            int count = dataset.getColumnCount();
            float x0 = (float) domainAxis.getCategoryStart(column, count,
                    dataArea, axisEdge);
            float x1 = (float) domainAxis.getCategoryMiddle(column, count,
                    dataArea, axisEdge);
            float x2 = (float) domainAxis.getCategoryEnd(column, count,
                    dataArea, axisEdge);

            x0 = Math.round(x0);
            x1 = Math.round(x1);
            x2 = Math.round(x2);

            if (this.endType == AreaRendererEndType.TRUNCATE) {
                if (column == 0) {
                    x0 = x1;
                }
                else if (column == getColumnCount() - 1) {
                    x2 = x1;
                }
            }

            double yy1 = value.doubleValue();

            double yy0 = 0.0;
            if (column > 0) {
                Number n0 = dataset.getValue(row, column - 1);
                if (n0 != null) {
                    yy0 = (n0.doubleValue() + yy1) / 2.0;
                }
            }

            double yy2 = 0.0;
            if (column < dataset.getColumnCount() - 1) {
                Number n2 = dataset.getValue(row, column + 1);
                if (n2 != null) {
                    yy2 = (n2.doubleValue() + yy1) / 2.0;
                }
            }

            RectangleEdge edge = plot.getRangeAxisEdge();
            float y0 = (float) rangeAxis.valueToJava2D(yy0, dataArea, edge);
            float y1 = (float) rangeAxis.valueToJava2D(yy1, dataArea, edge);
            float y2 = (float) rangeAxis.valueToJava2D(yy2, dataArea, edge);
            float yz = (float) rangeAxis.valueToJava2D(0.0, dataArea, edge);

            g2.setPaint(getItemPaint(row, column));
            g2.setStroke(getItemStroke(row, column));

            GeneralPath area = new GeneralPath();

            if (orientation == PlotOrientation.VERTICAL) {
                area.moveTo(x0, yz);
                area.lineTo(x0, y0);
                area.lineTo(x1, y1);
                area.lineTo(x2, y2);
                area.lineTo(x2, yz);
            }
            else if (orientation == PlotOrientation.HORIZONTAL) {
                area.moveTo(yz, x0);
                area.lineTo(y0, x0);
                area.lineTo(y1, x1);
                area.lineTo(y2, x2);
                area.lineTo(yz, x2);
            }
            area.closePath();

            g2.setPaint(getItemPaint(row, column));
            g2.fill(area);

            // draw the item labels if there are any...
            if (isItemLabelVisible(row, column)) {
                drawItemLabel(g2, orientation, dataset, row, column, x1, y1,
                        (value.doubleValue() < 0.0));
            }

            // submit the current data point as a crosshair candidate
            int datasetIndex = plot.indexOf(dataset);
            updateCrosshairValues(state.getCrosshairState(),
                    dataset.getRowKey(row), dataset.getColumnKey(column),
                    yy1, datasetIndex, x1, y1, orientation);

            // add an item entity, if this information is being collected
            EntityCollection entities = state.getEntityCollection();
            if (entities != null) {
                addItemEntity(entities, dataset, row, column, area);
            }
        }

    }

    /**
     * Tests this instance for equality with an arbitrary object.
     *
     * @param obj  the object to test (<code>null permitted).
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof AreaRenderer)) {
            return false;
        }
        AreaRenderer that = (AreaRenderer) obj;
        if (!this.endType.equals(that.endType)) {
            return false;
        }
        return super.equals(obj);
    }

    /**
     * Returns an independent copy of the renderer.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException  should not happen.
     */
    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

}