jfreechart example source code file (LevelRenderer.java)

This example jfreechart source code file (LevelRenderer.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

abstractcategoryitemrenderer, awt, categoryaxis, categoryaxis, categorydataset, categoryitemrendererstate, categoryitemrendererstate, categoryplot, default_item_margin, geometry, io, levelrenderer, levelrenderer, plotorientation, rectangle2d, rectangle2d, rectangleedge

The jfreechart LevelRenderer.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2009, 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.]
 *
 * ------------------
 * LevelRenderer.java
 * ------------------
 * (C) Copyright 2004-2009, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Peter Kolb (patch 2511330);
 *
 * Changes
 * -------
 * 09-Jan-2004 : Version 1 (DG);
 * 05-Nov-2004 : Modified drawItem() signature (DG);
 * 20-Apr-2005 : Renamed CategoryLabelGenerator
 *               --> CategoryItemLabelGenerator (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 23-Jan-2006 : Renamed getMaxItemWidth() --> getMaximumItemWidth() (DG);
 * 13-May-2008 : Code clean-up (DG);
 * 26-Jun-2008 : Added crosshair support (DG);
 * 23-Jan-2009 : Set more appropriate default shape in legend (DG);
 * 23-Jan-2009 : Added support for seriesVisible flags - see patch
 *               2511330 (PK)
 *
 */

package org.jfree.chart.renderer.category;

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Stroke;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.HashUtilities;
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.labels.CategoryItemLabelGenerator;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.data.category.CategoryDataset;
import org.jfree.ui.RectangleEdge;
import org.jfree.util.PublicCloneable;

/**
 * A {@link CategoryItemRenderer} that draws individual data items as
 * horizontal lines, spaced in the same way as bars in a bar chart.  The
 * example shown here is generated by the
 * <code>OverlaidBarChartDemo2.java program included in the JFreeChart
 * Demo Collection:
 * <br>

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

    /** For serialization. */
    private static final long serialVersionUID = -8204856624355025117L;

    /** The default item margin percentage. */
    public static final double DEFAULT_ITEM_MARGIN = 0.20;

    /** The margin between items within a category. */
    private double itemMargin;

    /** The maximum item width as a percentage of the available space. */
    private double maxItemWidth;

    /**
     * Creates a new renderer with default settings.
     */
    public LevelRenderer() {
        super();
        this.itemMargin = DEFAULT_ITEM_MARGIN;
        this.maxItemWidth = 1.0;  // 100 percent, so it will not apply unless
                                  // changed
        setBaseLegendShape(new Rectangle2D.Float(-5.0f, -1.0f, 10.0f, 2.0f));
        // set the outline paint to fully transparent, then the legend shape
        // will just have the same colour as the lines drawn by the renderer
        setBaseOutlinePaint(new Color(0, 0, 0, 0));
    }

    /**
     * Returns the item margin.
     *
     * @return The margin.
     *
     * @see #setItemMargin(double)
     */
    public double getItemMargin() {
        return this.itemMargin;
    }

    /**
     * Sets the item margin and sends a {@link RendererChangeEvent} to all
     * registered listeners.  The value is expressed as a percentage of the
     * available width for plotting all the bars, with the resulting amount to
     * be distributed between all the bars evenly.
     *
     * @param percent  the new margin.
     *
     * @see #getItemMargin()
     */
    public void setItemMargin(double percent) {
        this.itemMargin = percent;
        fireChangeEvent();
    }

    /**
     * Returns the maximum width, as a percentage of the available drawing
     * space.
     *
     * @return The maximum width.
     *
     * @see #setMaximumItemWidth(double)
     */
    public double getMaximumItemWidth() {
        return getMaxItemWidth();
    }

    /**
     * Sets the maximum item width, which is specified as a percentage of the
     * available space for all items, and sends a {@link RendererChangeEvent}
     * to all registered listeners.
     *
     * @param percent  the percent.
     *
     * @see #getMaximumItemWidth()
     */
    public void setMaximumItemWidth(double percent) {
        setMaxItemWidth(percent);
    }

    /**
     * Initialises the renderer and returns a state object that will be passed
     * to subsequent calls to the drawItem method.
     * <p>
     * This method gets called once at the start of the process of drawing a
     * chart.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area in which the data is to be plotted.
     * @param plot  the plot.
     * @param rendererIndex  the renderer index.
     * @param info  collects chart rendering information for return to caller.
     *
     * @return The renderer state.
     */
    public CategoryItemRendererState initialise(Graphics2D g2,
            Rectangle2D dataArea, CategoryPlot plot, int rendererIndex,
            PlotRenderingInfo info) {

        CategoryItemRendererState state = super.initialise(g2, dataArea, plot,
                rendererIndex, info);
        calculateItemWidth(plot, dataArea, rendererIndex, state);
        return state;

    }

    /**
     * Calculates the bar width and stores it in the renderer state.
     *
     * @param plot  the plot.
     * @param dataArea  the data area.
     * @param rendererIndex  the renderer index.
     * @param state  the renderer state.
     */
    protected void calculateItemWidth(CategoryPlot plot,
            Rectangle2D dataArea, int rendererIndex,
            CategoryItemRendererState state) {

        CategoryAxis domainAxis = getDomainAxis(plot, rendererIndex);
        CategoryDataset dataset = plot.getDataset(rendererIndex);
        if (dataset != null) {
            int columns = dataset.getColumnCount();
            int rows = state.getVisibleSeriesCount() >= 0
                    ? state.getVisibleSeriesCount() : dataset.getRowCount();
            double space = 0.0;
            PlotOrientation orientation = plot.getOrientation();
            if (orientation == PlotOrientation.HORIZONTAL) {
                space = dataArea.getHeight();
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                space = dataArea.getWidth();
            }
            double maxWidth = space * getMaximumItemWidth();
            double categoryMargin = 0.0;
            double currentItemMargin = 0.0;
            if (columns > 1) {
                categoryMargin = domainAxis.getCategoryMargin();
            }
            if (rows > 1) {
                currentItemMargin = getItemMargin();
            }
            double used = space * (1 - domainAxis.getLowerMargin()
                                     - domainAxis.getUpperMargin()
                                     - categoryMargin - currentItemMargin);
            if ((rows * columns) > 0) {
                state.setBarWidth(Math.min(used / (rows * columns), maxWidth));
            }
            else {
                state.setBarWidth(Math.min(used, maxWidth));
            }
        }
    }

    /**
     * Calculates the coordinate of the first "side" of a bar.  This will be
     * the minimum x-coordinate for a vertical bar, and the minimum
     * y-coordinate for a horizontal bar.
     *
     * @param plot  the plot.
     * @param orientation  the plot orientation.
     * @param dataArea  the data area.
     * @param domainAxis  the domain axis.
     * @param state  the renderer state (has the bar width precalculated).
     * @param row  the row index.
     * @param column  the column index.
     *
     * @return The coordinate.
     */
    protected double calculateBarW0(CategoryPlot plot,
                                    PlotOrientation orientation,
                                    Rectangle2D dataArea,
                                    CategoryAxis domainAxis,
                                    CategoryItemRendererState state,
                                    int row,
                                    int column) {
        // calculate bar width...
        double space = 0.0;
        if (orientation == PlotOrientation.HORIZONTAL) {
            space = dataArea.getHeight();
        }
        else {
            space = dataArea.getWidth();
        }
        double barW0 = domainAxis.getCategoryStart(column, getColumnCount(),
                dataArea, plot.getDomainAxisEdge());
        int seriesCount = state.getVisibleSeriesCount();
        if (seriesCount < 0) {
            seriesCount = getRowCount();
        }
        int categoryCount = getColumnCount();
        if (seriesCount > 1) {
            double seriesGap = space * getItemMargin()
                    / (categoryCount * (seriesCount - 1));
            double seriesW = calculateSeriesWidth(space, domainAxis,
                    categoryCount, seriesCount);
            barW0 = barW0 + row * (seriesW + seriesGap)
                          + (seriesW / 2.0) - (state.getBarWidth() / 2.0);
        }
        else {
            barW0 = domainAxis.getCategoryMiddle(column, getColumnCount(),
                    dataArea, plot.getDomainAxisEdge()) - state.getBarWidth()
                    / 2.0;
        }
        return barW0;
    }

    /**
     * Draws the bar for a single (series, category) data item.
     *
     * @param g2  the graphics device.
     * @param state  the renderer state.
     * @param dataArea  the data 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) {

        // nothing is drawn if the row index is not included in the list with
        // the indices of the visible rows...
        int visibleRow = state.getVisibleSeriesIndex(row);
        if (visibleRow < 0) {
            return;
        }

        // nothing is drawn for null values...
        Number dataValue = dataset.getValue(row, column);
        if (dataValue == null) {
            return;
        }

        double value = dataValue.doubleValue();

        PlotOrientation orientation = plot.getOrientation();
        double barW0 = calculateBarW0(plot, orientation, dataArea, domainAxis,
                state, visibleRow, column);
        RectangleEdge edge = plot.getRangeAxisEdge();
        double barL = rangeAxis.valueToJava2D(value, dataArea, edge);

        // draw the bar...
        Line2D line = null;
        double x = 0.0;
        double y = 0.0;
        if (orientation == PlotOrientation.HORIZONTAL) {
            x = barL;
            y = barW0 + state.getBarWidth() / 2.0;
            line = new Line2D.Double(barL, barW0, barL,
                    barW0 + state.getBarWidth());
        }
        else {
            x = barW0 + state.getBarWidth() / 2.0;
            y = barL;
            line = new Line2D.Double(barW0, barL, barW0 + state.getBarWidth(),
                    barL);
        }
        Stroke itemStroke = getItemStroke(row, column);
        Paint itemPaint = getItemPaint(row, column);
        g2.setStroke(itemStroke);
        g2.setPaint(itemPaint);
        g2.draw(line);

        CategoryItemLabelGenerator generator = getItemLabelGenerator(row,
                column);
        if (generator != null && isItemLabelVisible(row, column)) {
            drawItemLabel(g2, orientation, dataset, row, column, x, y,
                    (value < 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), value,
                datasetIndex, barW0, barL, orientation);

        // collect entity and tool tip information...
        EntityCollection entities = state.getEntityCollection();
        if (entities != null) {
            addItemEntity(entities, dataset, row, column, line.getBounds());
        }

    }

    /**
     * Calculates the available space for each series.
     *
     * @param space  the space along the entire axis (in Java2D units).
     * @param axis  the category axis.
     * @param categories  the number of categories.
     * @param series  the number of series.
     *
     * @return The width of one series.
     */
    protected double calculateSeriesWidth(double space, CategoryAxis axis,
                                          int categories, int series) {
        double factor = 1.0 - getItemMargin() - axis.getLowerMargin()
                        - axis.getUpperMargin();
        if (categories > 1) {
            factor = factor - axis.getCategoryMargin();
        }
        return (space * factor) / (categories * series);
    }

    /**
     * Returns the Java2D coordinate for the middle of the specified data item.
     *
     * @param rowKey  the row key.
     * @param columnKey  the column key.
     * @param dataset  the dataset.
     * @param axis  the axis.
     * @param area  the drawing area.
     * @param edge  the edge along which the axis lies.
     *
     * @return The Java2D coordinate.
     *
     * @since 1.0.11
     */
    public double getItemMiddle(Comparable rowKey, Comparable columnKey,
            CategoryDataset dataset, CategoryAxis axis, Rectangle2D area,
            RectangleEdge edge) {
        return axis.getCategorySeriesMiddle(columnKey, rowKey, dataset,
                this.itemMargin, area, edge);
    }

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

    /**
     * Returns a hash code for this instance.
     *
     * @return A hash code.
     */
    public int hashCode() {
        int hash = super.hashCode();
        hash = HashUtilities.hashCode(hash, this.itemMargin);
        hash = HashUtilities.hashCode(hash, this.maxItemWidth);
        return hash;
    }

    /**
     * Returns the maximum width, as a percentage of the available drawing
     * space.
     *
     * @return The maximum width.
     *
     * @deprecated Use {@link #getMaximumItemWidth()} instead.
     */
    public double getMaxItemWidth() {
        return this.maxItemWidth;
    }

    /**
     * Sets the maximum item width, which is specified as a percentage of the
     * available space for all items, and sends a {@link RendererChangeEvent}
     * to all registered listeners.
     *
     * @param percent  the percent.
     *
     * @deprecated Use {@link #setMaximumItemWidth(double)} instead.
     */
    public void setMaxItemWidth(double percent) {
        this.maxItemWidth = percent;
        fireChangeEvent();
    }

}