001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
006     *
007     * Project Info:  http://www.jfree.org/jfreechart/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it 
010     * under the terms of the GNU Lesser General Public License as published by 
011     * the Free Software Foundation; either version 2.1 of the License, or 
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but 
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022     * USA.  
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025     * in the United States and other countries.]
026     *
027     * -------------------------
028     * CategoryStepRenderer.java
029     * -------------------------
030     *
031     * (C) Copyright 2004-2007, by Brian Cole and Contributors.
032     *
033     * Original Author:  Brian Cole;
034     * Contributor(s):   David Gilbert (for Object Refinery Limited);
035     *
036     * $Id: CategoryStepRenderer.java,v 1.5.2.3 2007/02/22 11:38:18 mungady Exp $
037     *
038     * Changes
039     * -------
040     * 21-Apr-2004 : Version 1, contributed by Brian Cole (DG);
041     * 22-Apr-2004 : Fixed Checkstyle complaints (DG);
042     * 05-Nov-2004 : Modified drawItem() signature (DG);
043     * 08-Mar-2005 : Added equals() method (DG);
044     * ------------- JFREECHART 1.0.x ---------------------------------------------
045     * 30-Nov-2006 : Added checks for series visibility (DG);
046     * 22-Feb-2007 : Use new state object for reusable line, enable chart entities 
047     *               (for tooltips, URLs), added new getLegendItem() override (DG);
048     * 
049     */
050    
051    package org.jfree.chart.renderer.category;
052    
053    import java.awt.Graphics2D;
054    import java.awt.Paint;
055    import java.awt.Shape;
056    import java.awt.geom.Line2D;
057    import java.awt.geom.Rectangle2D;
058    import java.io.Serializable;
059    
060    import org.jfree.chart.LegendItem;
061    import org.jfree.chart.axis.CategoryAxis;
062    import org.jfree.chart.axis.ValueAxis;
063    import org.jfree.chart.entity.EntityCollection;
064    import org.jfree.chart.event.RendererChangeEvent;
065    import org.jfree.chart.plot.CategoryPlot;
066    import org.jfree.chart.plot.PlotOrientation;
067    import org.jfree.chart.plot.PlotRenderingInfo;
068    import org.jfree.chart.renderer.xy.XYStepRenderer;
069    import org.jfree.data.category.CategoryDataset;
070    import org.jfree.util.PublicCloneable;
071    
072    /**
073     * A "step" renderer similar to {@link XYStepRenderer} but
074     * that can be used with the {@link CategoryPlot} class.
075     */
076    public class CategoryStepRenderer extends AbstractCategoryItemRenderer
077                                      implements Cloneable, PublicCloneable, 
078                                                 Serializable {
079    
080        /**
081         * State information for the renderer.
082         */
083        protected static class State extends CategoryItemRendererState {
084    
085            /** 
086             * A working line for re-use to avoid creating large numbers of
087             * objects.
088             */
089            public Line2D line;
090            
091            /**
092             * Creates a new state instance.
093             * 
094             * @param info  collects plot rendering information (<code>null</code> 
095             *              permitted).
096             */
097            public State(PlotRenderingInfo info) {
098                super(info);
099                this.line = new Line2D.Double();
100            }
101            
102        }
103        
104        /** For serialization. */
105        private static final long serialVersionUID = -5121079703118261470L;
106        
107        /** The stagger width. */
108        public static final int STAGGER_WIDTH = 5; // could make this configurable
109      
110        /** 
111         * A flag that controls whether or not the steps for multiple series are 
112         * staggered. 
113         */
114        private boolean stagger = false;
115    
116        /** 
117         * Creates a new renderer (stagger defaults to <code>false</code>).
118         */
119        public CategoryStepRenderer() {
120            this(false);
121        }
122        
123        /**
124         * Creates a new renderer.
125         *  
126         * @param stagger  should the horizontal part of the step be staggered by 
127         *                 series? 
128         */
129        public CategoryStepRenderer(boolean stagger) {
130            this.stagger = stagger;
131        }
132      
133        /**
134         * Returns the flag that controls whether the series steps are staggered.
135         * 
136         * @return A boolean.
137         */
138        public boolean getStagger() {
139            return this.stagger;
140        }
141        
142        /**
143         * Sets the flag that controls whether or not the series steps are 
144         * staggered and sends a {@link RendererChangeEvent} to all registered
145         * listeners.
146         * 
147         * @param shouldStagger  a boolean.
148         */
149        public void setStagger(boolean shouldStagger) {
150            this.stagger = shouldStagger;
151            notifyListeners(new RendererChangeEvent(this));
152        }
153    
154        /**
155         * Returns a legend item for a series.
156         *
157         * @param datasetIndex  the dataset index (zero-based).
158         * @param series  the series index (zero-based).
159         *
160         * @return The legend item.
161         */
162        public LegendItem getLegendItem(int datasetIndex, int series) {
163    
164            CategoryPlot p = getPlot();
165            if (p == null) {
166                return null;
167            }
168    
169            // check that a legend item needs to be displayed...
170            if (!isSeriesVisible(series) || !isSeriesVisibleInLegend(series)) {
171                return null;
172            }
173    
174            CategoryDataset dataset;
175            dataset = p.getDataset(datasetIndex);
176            String label = getLegendItemLabelGenerator().generateLabel(dataset, 
177                    series);
178            String description = label;
179            String toolTipText = null; 
180            if (getLegendItemToolTipGenerator() != null) {
181                toolTipText = getLegendItemToolTipGenerator().generateLabel(
182                        dataset, series);   
183            }
184            String urlText = null;
185            if (getLegendItemURLGenerator() != null) {
186                urlText = getLegendItemURLGenerator().generateLabel(dataset, 
187                        series);   
188            }
189            Shape shape = new Rectangle2D.Double(-4.0, -3.0, 8.0, 6.0);
190            Paint paint = getSeriesPaint(series);
191         
192            LegendItem item = new LegendItem(label, description, toolTipText, 
193                    urlText, shape, paint);
194            item.setSeriesIndex(series);
195            item.setDatasetIndex(datasetIndex);
196            return item;
197        }
198    
199        /**
200         * Creates a new state instance.  This method is called from 
201         * {@link #initialise(Graphics2D, Rectangle2D, CategoryPlot, int, 
202         * PlotRenderingInfo)}, and we override it to ensure that the state
203         * contains a working Line2D instance.
204         * 
205         * @param info  the plot rendering info (<code>null</code> is permitted).
206         * 
207         * @return A new state instance.
208         */
209        protected CategoryItemRendererState createState(PlotRenderingInfo info) {
210            return new State(info);
211        }
212    
213        /**
214         * Draws a line taking into account the specified orientation.
215         * <p>
216         * In version 1.0.5, the signature of this method was changed by the 
217         * addition of the 'state' parameter.  This is an incompatible change, but
218         * is considered a low risk because it is unlikely that anyone has 
219         * subclassed this renderer.  If this *does* cause trouble for you, please
220         * report it as a bug.
221         * 
222         * @param g2  the graphics device.
223         * @param state  the renderer state.
224         * @param orientation  the plot orientation.
225         * @param x0  the x-coordinate for the start of the line.
226         * @param y0  the y-coordinate for the start of the line.
227         * @param x1  the x-coordinate for the end of the line.
228         * @param y1  the y-coordinate for the end of the line.
229         */
230        protected void drawLine(Graphics2D g2, State state, 
231                PlotOrientation orientation, double x0, double y0, double x1, 
232                double y1) {
233         
234            if (orientation == PlotOrientation.VERTICAL) {
235                state.line.setLine(x0, y0, x1, y1);
236                g2.draw(state.line);
237            }
238            else if (orientation == PlotOrientation.HORIZONTAL) {
239                state.line.setLine(y0, x0, y1, x1); // switch x and y
240                g2.draw(state.line);
241            }
242    
243        }
244    
245        /**
246         * Draw a single data item.
247         *
248         * @param g2  the graphics device.
249         * @param state  the renderer state.
250         * @param dataArea  the area in which the data is drawn.
251         * @param plot  the plot.
252         * @param domainAxis  the domain axis.
253         * @param rangeAxis  the range axis.
254         * @param dataset  the dataset.
255         * @param row  the row index (zero-based).
256         * @param column  the column index (zero-based).
257         * @param pass  the pass index.
258         */
259        public void drawItem(Graphics2D g2,
260                             CategoryItemRendererState state,
261                             Rectangle2D dataArea,
262                             CategoryPlot plot,
263                             CategoryAxis domainAxis,
264                             ValueAxis rangeAxis,
265                             CategoryDataset dataset,
266                             int row,
267                             int column,
268                             int pass) {
269    
270            // do nothing if item is not visible
271            if (!getItemVisible(row, column)) {
272                return;   
273            }
274            
275            Number value = dataset.getValue(row, column);
276            if (value == null) {
277                return;
278            }
279            PlotOrientation orientation = plot.getOrientation();
280    
281            // current data point...
282            double x1s = domainAxis.getCategoryStart(column, getColumnCount(), 
283                    dataArea, plot.getDomainAxisEdge());
284            double x1 = domainAxis.getCategoryMiddle(column, getColumnCount(), 
285                    dataArea, plot.getDomainAxisEdge());
286            double x1e = 2 * x1 - x1s; // or: x1s + 2*(x1-x1s)
287            double y1 = rangeAxis.valueToJava2D(value.doubleValue(), dataArea, 
288                    plot.getRangeAxisEdge());
289            g2.setPaint(getItemPaint(row, column));
290            g2.setStroke(getItemStroke(row, column));
291    
292            if (column != 0) {
293                Number previousValue = dataset.getValue(row, column - 1);
294                if (previousValue != null) {
295                    // previous data point...
296                    double previous = previousValue.doubleValue();
297                    double x0s = domainAxis.getCategoryStart(column - 1, 
298                            getColumnCount(), dataArea, plot.getDomainAxisEdge());
299                    double x0 = domainAxis.getCategoryMiddle(column - 1, 
300                            getColumnCount(), dataArea, plot.getDomainAxisEdge());
301                    double x0e = 2 * x0 - x0s; // or: x0s + 2*(x0-x0s)
302                    double y0 = rangeAxis.valueToJava2D(previous, dataArea, 
303                            plot.getRangeAxisEdge());
304                    if (getStagger()) {
305                        int xStagger = row * STAGGER_WIDTH;
306                        if (xStagger > (x1s - x0e)) {
307                            xStagger = (int) (x1s - x0e);
308                        }
309                        x1s = x0e + xStagger;
310                    }
311                    drawLine(g2, (State) state, orientation, x0e, y0, x1s, y0); 
312                    // extend x0's flat bar
313    
314                    drawLine(g2, (State) state, orientation, x1s, y0, x1s, y1); 
315                    // upright bar
316               }
317           }
318           drawLine(g2, (State) state, orientation, x1s, y1, x1e, y1); 
319           // x1's flat bar
320    
321           // draw the item labels if there are any...
322           if (isItemLabelVisible(row, column)) {
323                drawItemLabel(g2, orientation, dataset, row, column, x1, y1, 
324                        (value.doubleValue() < 0.0));
325           }
326    
327           // add an item entity, if this information is being collected
328           EntityCollection entities = state.getEntityCollection();
329           if (entities != null) {
330               Rectangle2D hotspot = new Rectangle2D.Double();
331               if (orientation == PlotOrientation.VERTICAL) {
332                   hotspot.setRect(x1s, y1, x1e - x1s, 4.0);
333               }
334               else {
335                   hotspot.setRect(y1 - 2.0, x1s, 4.0, x1e - x1s);
336               }
337               addItemEntity(entities, dataset, row, column, hotspot);
338           }
339    
340        }
341        
342        /**
343         * Tests this renderer for equality with an arbitrary object.
344         * 
345         * @param obj  the object (<code>null</code> permitted).
346         * 
347         * @return A boolean.
348         */
349        public boolean equals(Object obj) {
350            if (obj == this) {
351                return true;   
352            }
353            if (!(obj instanceof CategoryStepRenderer)) {
354                return false;   
355            }
356            CategoryStepRenderer that = (CategoryStepRenderer) obj;
357            if (this.stagger != that.stagger) {
358                return false;   
359            }
360            return super.equals(obj);
361        }
362    
363    }