gt:                         double previous = previousValue.doubleValue();
context: /* ===========================================================
   * 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.]
   *
   * ---------------------------
   * MinMaxCategoryRenderer.java
   * ---------------------------
   * (C) Copyright 2002-2009, by Object Refinery Limited.
   *
   * Original Author:  Tomer Peretz;
   * Contributor(s):   David Gilbert (for Object Refinery Limited);
   *                   Christian W. Zuckschwerdt;
   *                   Nicolas Brodu (for Astrium and EADS Corporate Research
   *                   Center);
   *
   * Changes:
   * --------
   * 29-May-2002 : Version 1 (TP);
   * 02-Oct-2002 : Fixed errors reported by Checkstyle (DG);
   * 24-Oct-2002 : Amendments for changes in CategoryDataset interface and
   *               CategoryToolTipGenerator interface (DG);
   * 05-Nov-2002 : Base dataset is now TableDataset not CategoryDataset (DG);
   * 17-Jan-2003 : Moved plot classes to a separate package (DG);
   * 10-Apr-2003 : Changed CategoryDataset to KeyedValues2DDataset in drawItem()
   *               method (DG);
   * 30-Jul-2003 : Modified entity constructor (CZ);
   * 08-Sep-2003 : Implemented Serializable (NB);
   * 29-Oct-2003 : Added workaround for font alignment in PDF output (DG);
   * 05-Nov-2004 : Modified drawItem() signature (DG);
   * 17-Nov-2005 : Added change events and argument checks (DG);
   * ------------- JFREECHART 1.0.x ---------------------------------------------
   * 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
   * 09-Mar-2007 : Fixed problem with horizontal rendering (DG);
   * 21-Jun-2007 : Removed JCommon dependencies (DG);
   * 28-Sep-2007 : Added equals() method override (DG);
   *
   */
  
  package org.jfree.chart.renderer.category;
  
  import java.awt.BasicStroke;
  import java.awt.Color;
  import java.awt.Component;
  import java.awt.Graphics;
  import java.awt.Graphics2D;
  import java.awt.Paint;
  import java.awt.Shape;
  import java.awt.Stroke;
  import java.awt.geom.AffineTransform;
  import java.awt.geom.Arc2D;
  import java.awt.geom.GeneralPath;
  import java.awt.geom.Line2D;
  import java.awt.geom.Rectangle2D;
  import java.io.IOException;
  import java.io.ObjectInputStream;
  import java.io.ObjectOutputStream;
  
  import javax.swing.Icon;
  
  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.util.PaintUtilities;
  import org.jfree.chart.util.SerialUtilities;
  import org.jfree.data.category.CategoryDataset;
  
  /**
   * Renderer for drawing min max plot. This renderer draws all the series under
   * the same category in the same x position using <code>objectIcon</code> and
   * a line from the maximum value to the minimum value. For use with the
   * {@link CategoryPlot} class. The example shown here is generated by
   * the <code>MinMaxCategoryPlotDemo1.java</code> program included in the
   * JFreeChart Demo Collection:
   * <br><br>
   * <img src="../../../../../images/MinMaxCategoryRendererSample.png"
   * alt="MinMaxCategoryRendererSample.png" />
   */
  public class MinMaxCategoryRenderer extends AbstractCategoryItemRenderer {
  
      /** For serialization. */
      private static final long serialVersionUID = 2935615937671064911L;
  
      /** A flag indicating whether or not lines are drawn between XY points. */
      private boolean plotLines = false;
  
      /**
       * The paint of the line between the minimum value and the maximum value.
       */
      private transient Paint groupPaint = Color.black;
  
      /**
       * The stroke of the line between the minimum value and the maximum value.
       */
      private transient Stroke groupStroke = new BasicStroke(1.0f);
  
      /** The icon used to indicate the minimum value.*/
      private transient Icon minIcon = getIcon(new Arc2D.Double(-4, -4, 8, 8, 0,
              360, Arc2D.OPEN), null, Color.black);
  
      /** The icon used to indicate the maximum value.*/
      private transient Icon maxIcon = getIcon(new Arc2D.Double(-4, -4, 8, 8, 0,
              360, Arc2D.OPEN), null, Color.black);
  
      /** The icon used to indicate the values.*/
      private transient Icon objectIcon = getIcon(new Line2D.Double(-4, 0, 4, 0),
              false, true);
  
      /** The last category. */
      private int lastCategory = -1;
  
      /** The minimum. */
      private double min;
  
      /** The maximum. */
      private double max;
  
      /**
       * Default constructor.
       */
      public MinMaxCategoryRenderer() {
          super();
      }
  
      /**
       * Gets whether or not lines are drawn between category points.
       *
       * @return boolean true if line will be drawn between sequenced categories,
       *         otherwise false.
       *
       * @see #setDrawLines(boolean)
       */
      public boolean isDrawLines() {
          return this.plotLines;
      }
  
      /**
       * Sets the flag that controls whether or not lines are drawn to connect
       * the items within a series and sends a {@link RendererChangeEvent} to
       * all registered listeners.
       *
       * @param draw  the new value of the flag.
       *
       * @see #isDrawLines()
       */
      public void setDrawLines(boolean draw) {
          if (this.plotLines != draw) {
              this.plotLines = draw;
              fireChangeEvent();
          }
  
      }
  
      /**
       * Returns the paint used to draw the line between the minimum and maximum
       * value items in each category.
       *
       * @return The paint (never <code>null</code>).
       *
       * @see #setGroupPaint(Paint)
       */
      public Paint getGroupPaint() {
          return this.groupPaint;
      }
  
      /**
       * Sets the paint used to draw the line between the minimum and maximum
       * value items in each category and sends a {@link RendererChangeEvent} to
       * all registered listeners.
       *
       * @param paint  the paint (<code>null</code> not permitted).
       *
       * @see #getGroupPaint()
       */
      public void setGroupPaint(Paint paint) {
          if (paint == null) {
              throw new IllegalArgumentException("Null 'paint' argument.");
          }
          this.groupPaint = paint;
          fireChangeEvent();
      }
  
      /**
       * Returns the stroke used to draw the line between the minimum and maximum
       * value items in each category.
       *
       * @return The stroke (never <code>null</code>).
       *
       * @see #setGroupStroke(Stroke)
       */
      public Stroke getGroupStroke() {
          return this.groupStroke;
      }
  
      /**
       * Sets the stroke of the line between the minimum value and the maximum
       * value and sends a {@link RendererChangeEvent} to all registered
       * listeners.
       *
       * @param stroke the new stroke (<code>null</code> not permitted).
       */
      public void setGroupStroke(Stroke stroke) {
          if (stroke == null) {
              throw new IllegalArgumentException("Null 'stroke' argument.");
          }
          this.groupStroke = stroke;
          fireChangeEvent();
      }
  
      /**
       * Returns the icon drawn for each data item.
       *
       * @return The icon (never <code>null</code>).
       *
       * @see #setObjectIcon(Icon)
       */
      public Icon getObjectIcon() {
          return this.objectIcon;
      }
  
      /**
       * Sets the icon drawn for each data item and sends a
       * {@link RendererChangeEvent} to all registered listeners.
       *
       * @param icon  the icon.
       *
       * @see #getObjectIcon()
       */
      public void setObjectIcon(Icon icon) {
          if (icon == null) {
              throw new IllegalArgumentException("Null 'icon' argument.");
          }
          this.objectIcon = icon;
          fireChangeEvent();
      }
  
      /**
       * Returns the icon displayed for the maximum value data item within each
       * category.
       *
       * @return The icon (never <code>null</code>).
       *
       * @see #setMaxIcon(Icon)
       */
      public Icon getMaxIcon() {
          return this.maxIcon;
      }
  
      /**
       * Sets the icon displayed for the maximum value data item within each
       * category and sends a {@link RendererChangeEvent} to all registered
       * listeners.
       *
       * @param icon  the icon (<code>null</code> not permitted).
       *
       * @see #getMaxIcon()
       */
      public void setMaxIcon(Icon icon) {
          if (icon == null) {
              throw new IllegalArgumentException("Null 'icon' argument.");
          }
          this.maxIcon = icon;
          fireChangeEvent();
      }
  
      /**
       * Returns the icon displayed for the minimum value data item within each
       * category.
       *
       * @return The icon (never <code>null</code>).
       *
       * @see #setMinIcon(Icon)
       */
      public Icon getMinIcon() {
          return this.minIcon;
      }
  
      /**
       * Sets the icon displayed for the minimum value data item within each
       * category and sends a {@link RendererChangeEvent} to all registered
       * listeners.
       *
       * @param icon  the icon (<code>null</code> not permitted).
       *
       * @see #getMinIcon()
       */
      public void setMinIcon(Icon icon) {
          if (icon == null) {
              throw new IllegalArgumentException("Null 'icon' argument.");
          }
          this.minIcon = icon;
          fireChangeEvent();
      }
  
      /**
       * Draw a single data item.
       *
       * @param g2  the graphics device.
       * @param state  the renderer state.
       * @param dataArea  the area in which the data is drawn.
       * @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,
              boolean selected, int pass) {
  
          // first check the number we are plotting...
          Number value = dataset.getValue(row, column);
          if (value != null) {
              // current data point...
              double x1 = domainAxis.getCategoryMiddle(column, getColumnCount(),
                      dataArea, plot.getDomainAxisEdge());
              double y1 = rangeAxis.valueToJava2D(value.doubleValue(), dataArea,
                      plot.getRangeAxisEdge());
              g2.setPaint(getItemPaint(row, column, selected));
              g2.setStroke(getItemStroke(row, column, selected));
              Shape shape = null;
              shape = new Rectangle2D.Double(x1 - 4, y1 - 4, 8.0, 8.0);
  
              PlotOrientation orient = plot.getOrientation();
              if (orient == PlotOrientation.VERTICAL) {
                  this.objectIcon.paintIcon(null, g2, (int) x1, (int) y1);
              }
              else {
                  this.objectIcon.paintIcon(null, g2, (int) y1, (int) x1);
              }
  
              if (this.lastCategory == column) {
                  if (this.min > value.doubleValue()) {
                      this.min = value.doubleValue();
                  }
                  if (this.max < value.doubleValue()) {
                      this.max = value.doubleValue();
                  }
  
                  // last series, so we are ready to draw the min and max
                  if (dataset.getRowCount() - 1 == row) {
                      g2.setPaint(this.groupPaint);
                      g2.setStroke(this.groupStroke);
                      double minY = rangeAxis.valueToJava2D(this.min, dataArea,
                              plot.getRangeAxisEdge());
                      double maxY = rangeAxis.valueToJava2D(this.max, dataArea,
                              plot.getRangeAxisEdge());
  
                      if (orient == PlotOrientation.VERTICAL) {
                          g2.draw(new Line2D.Double(x1, minY, x1, maxY));
                          this.minIcon.paintIcon(null, g2, (int) x1, (int) minY);
                          this.maxIcon.paintIcon(null, g2, (int) x1, (int) maxY);
                      }
                      else {
                          g2.draw(new Line2D.Double(minY, x1, maxY, x1));
                          this.minIcon.paintIcon(null, g2, (int) minY, (int) x1);
                          this.maxIcon.paintIcon(null, g2, (int) maxY, (int) x1);
                      }
                  }
              }
              else {  // reset the min and max
                  this.lastCategory = column;
                  this.min = value.doubleValue();
                  this.max = value.doubleValue();
              }
  
              // connect to the previous point
              if (this.plotLines) {
                  if (column != 0) {
                      Number previousValue = dataset.getValue(row, column - 1);
                      if (previousValue != null) {
                          // previous data point...
  