categorysteprenderer.java

这是一个segy数据显示程序

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2004, 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., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 *
 * -------------------------
 * CategoryStepRenderer.java
 * -------------------------
 *
 * (C) Copyright 2004, by Brian Cole and Contributors.
 *
 * Original Author:  Brian Cole;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * $Id: CategoryStepRenderer.java,v 1.3 2004/06/07 14:48:06 mungady Exp $
 *
 * Changes
 * -------
 * 21-Apr-2004 : Version 1, contributed by Brian Cole (DG);
 * 22-Apr-2004 : Fixed Checkstyle complaints (DG);
 * 
 */

package org.jfree.chart.renderer;

import java.awt.Graphics2D;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.CategoryDataset;
import org.jfree.util.PublicCloneable;

/**
 * A "step" renderer similar to {@link XYStepRenderer} but
 * that can be used with the {@link CategoryPlot} class.
 *
 * @author Brian Cole
 */
public class CategoryStepRenderer extends AbstractCategoryItemRenderer
                                  implements Cloneable, PublicCloneable, Serializable {

    /** The stagger width. */
    public static final int STAGGER_WIDTH = 5; // could make this configurable...
  
    /** A flag that controls whether or not the steps for multiple series are staggered. */
    private boolean stagger = false;
    
    /** A working line - need to remove this. */
    private transient Line2D line = new Line2D.Double(0.0, 0.0, 0.0, 0.0);

    /** 
     * Creates a new renderer (stagger defaults to false).
     */
    public CategoryStepRenderer() {
        this(false);
    }
    
    /**
     * Creates a new renderer.
     *  
     * @param stagger  should the horizontal part of the step be staggered by series? 
     */
    public CategoryStepRenderer(boolean stagger) {
        this.stagger = stagger;
    }
  
    /**
     * Returns the flag that controls whether the series steps are staggered.
     * 
     * @return A boolean.
     */
    public boolean getStagger() {
        return stagger;
    }
    
    /**
     * Sets the flag that controls whether or not the series steps are staggered.
     * 
     * @param shouldStagger  a boolean.
     */
    public void setStagger(boolean shouldStagger) {
        stagger = shouldStagger;
    }
   
    /**
     * Draws the line.
     * 
     * @param g2  the graphics device.
     * @param orientation  the plot orientation.
     * @param x0  the x-coordinate for the start of the line.
     * @param y0  the y-coordinate for the start of the line.
     * @param x1  the x-coordinate for the end of the line.
     * @param y1  the y-coordinate for the end of the line.
     */
    protected void drawLine(Graphics2D g2, PlotOrientation orientation,
                            double x0, double y0, double x1, double y1) {
     
        if (orientation == PlotOrientation.VERTICAL) {
            line.setLine(x0, y0, x1, y1);
            g2.draw(line);
        }
        else if (orientation == PlotOrientation.HORIZONTAL) {
            line.setLine(y0, x0, y1, x1); // switch x and y
            g2.draw(line);
        }
        // else unknown orientation (complain?)
    }

    /**
     * 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).
     */
    public void drawItem(Graphics2D g2,
                         CategoryItemRendererState state,
                         Rectangle2D dataArea,
                         CategoryPlot plot,
                         CategoryAxis domainAxis,
                         ValueAxis rangeAxis,
                         CategoryDataset dataset,
                         int row,
                         int column) {

        Number value = dataset.getValue(row, column);
        if (value == null) {
            return;
        }
        PlotOrientation orientation = plot.getOrientation();

        // current data point...
        double x1s = domainAxis.getCategoryStart(
            column, getColumnCount(), dataArea, plot.getDomainAxisEdge()
        );
        double x1 = domainAxis.getCategoryMiddle(
            column, getColumnCount(), dataArea, plot.getDomainAxisEdge()
        );
        double x1e = 2 * x1 - x1s; // or: x1s + 2*(x1-x1s)
        double y1 = rangeAxis.valueToJava2D(value.doubleValue(), dataArea, plot.getRangeAxisEdge());
        g2.setPaint(getItemPaint(row, column));
        g2.setStroke(getItemStroke(row, column));

        if (column != 0) {
            Number previousValue = dataset.getValue(row, column - 1);
            if (previousValue != null) {
                // previous data point...
                double previous = previousValue.doubleValue();
                double x0s = domainAxis.getCategoryStart(
                    column - 1, getColumnCount(), dataArea, plot.getDomainAxisEdge()
                );
                double x0 = domainAxis.getCategoryMiddle(
                    column - 1, getColumnCount(), dataArea, plot.getDomainAxisEdge()
                );
                double x0e = 2 * x0 - x0s; // or: x0s + 2*(x0-x0s)
                double y0 = rangeAxis.valueToJava2D(previous, dataArea, plot.getRangeAxisEdge());
                if (getStagger()) {
                    int xStagger = row * STAGGER_WIDTH;
                    if (xStagger > (x1s - x0e)) {
                        xStagger = (int) (x1s - x0e);
                    }
                    x1s = x0e + xStagger;
                }
                drawLine(g2, orientation, x0e, y0, x1s, y0); // extend x0's flat bar

                drawLine(g2, orientation, x1s, y0, x1s, y1); // upright bar
           }
       }
       drawLine(g2, orientation, x1s, y1, x1e, y1); // x1's flat bar

       // draw the item labels if there are any...
       if (isItemLabelVisible(row, column)) {
            drawItemLabel(
                g2, orientation, dataset, row, column, x1, y1, (value.doubleValue() < 0.0)
            );
       }
    /* This is how LineAndShapeRenderer.drawItem() handles tips and URLs, but
       I omit it due to time pressure. It shouldn't be hard to put back
 in.

       // collect entity and tool tip information...
       if (state.getInfo() != null) {
           EntityCollection entities =
 state.getInfo().getOwner().getEntityCollection();
           if (entities != null && shape != null) {
               String tip = null;
               CategoryItemLabelGenerator generator =
 getItemLabelGenerator(row, column);
               if (generator != null) {
                   tip = generator.generateToolTip(dataset, row, column);
               }
               String url = null;
               if (getItemURLGenerator(row, column) != null)                    
               url = getItemURLGenerator(row, column).generateURL(dataset, row, column);
               }
               CategoryItemEntity entity = new CategoryItemEntity(
                   shape, tip, url, dataset, row,
 dataset.getColumnKey(column), column);
               entities.addEntity(entity);
           }
       }
    */

    }

}