001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2022, by David Gilbert 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 */
028
029package org.jfree.chart.text;
030
031import java.awt.Font;
032import java.awt.Graphics2D;
033import java.awt.Paint;
034import java.awt.Shape;
035import java.awt.geom.Rectangle2D;
036import java.io.Serializable;
037import java.util.ArrayList;
038import java.util.Collections;
039import java.util.List;
040import org.jfree.chart.api.HorizontalAlignment;
041import org.jfree.chart.block.Size2D;
042import org.jfree.chart.internal.Args;
043import org.jfree.chart.internal.ShapeUtils;
044
045/**
046 * A list of {@link TextLine} objects that form a block of text.
047 * 
048 * @see TextUtils#createTextBlock(String, Font, Paint)
049 */
050public class TextBlock implements Serializable {
051
052    /** For serialization. */
053    private static final long serialVersionUID = -4333175719424385526L;
054    
055    /** Storage for the lines of text. */
056    private List<TextLine> lines;
057    
058    /** The alignment of the lines. */
059    private HorizontalAlignment lineAlignment;
060
061    /**
062     * Creates a new empty text block.
063     */
064    public TextBlock() {
065        this.lines = new ArrayList<>();
066        this.lineAlignment = HorizontalAlignment.CENTER;
067    }
068    
069    /**
070     * Returns the alignment of the lines of text within the block.
071     * 
072     * @return The alignment (never {@code null}).
073     */
074    public HorizontalAlignment getLineAlignment() {
075        return this.lineAlignment;   
076    }
077    
078    /**
079     * Sets the alignment of the lines of text within the block.
080     * 
081     * @param alignment  the alignment ({@code null} not permitted).
082     */
083    public void setLineAlignment(HorizontalAlignment alignment) {
084        Args.nullNotPermitted(alignment, "alignment");
085        this.lineAlignment = alignment;   
086    }
087    
088    /**
089     * Adds a line of text that will be displayed using the specified font and
090     * color.
091     * 
092     * @param text  the text ({@code null} not permitted).
093     * @param font  the font ({@code null} not permitted).
094     * @param paint  the paint ({@code null} not permitted).
095     */
096    public void addLine(String text, Font font, Paint paint) {
097        addLine(new TextLine(text, font, paint));
098    }
099    
100    /**
101     * Adds a {@link TextLine} to the block.
102     * 
103     * @param line  the line.
104     */
105    public void addLine(TextLine line) {
106        this.lines.add(line);    
107    }
108    
109    /**
110     * Returns the last line in the block.
111     * 
112     * @return The last line in the block.
113     */
114    public TextLine getLastLine() {
115        TextLine last = null;
116        final int index = this.lines.size() - 1;
117        if (index >= 0) {
118            last = this.lines.get(index);
119        }
120        return last;
121    }
122    
123    /**
124     * Returns an unmodifiable list containing the lines for the text block.
125     *
126     * @return A list of {@link TextLine} objects.
127     */
128    public List<TextLine> getLines() {
129        return Collections.unmodifiableList(this.lines);
130    }
131    
132    /**
133     * Returns the width and height of the text block.
134     * 
135     * @param g2  the graphics device.
136     * 
137     * @return The width and height.
138     */
139    public Size2D calculateDimensions(Graphics2D g2) {
140        double width = 0.0;
141        double height = 0.0;
142        for (TextLine line : this.lines) {
143            final Size2D dimension = line.calculateDimensions(g2);
144            width = Math.max(width, dimension.getWidth());
145            height = height + dimension.getHeight();
146        }
147        return new Size2D(width, height);
148    }
149    
150    /**
151     * Returns the bounds of the text block.
152     * 
153     * @param g2  the graphics device ({@code null} not permitted).
154     * @param anchorX  the x-coordinate for the anchor point.
155     * @param anchorY  the y-coordinate for the anchor point.
156     * @param anchor  the text block anchor ({@code null} not permitted).
157     * @param rotateX  the x-coordinate for the rotation point.
158     * @param rotateY  the y-coordinate for the rotation point.
159     * @param angle  the rotation angle.
160     * 
161     * @return The bounds.
162     */
163    public Shape calculateBounds(Graphics2D g2, float anchorX, float anchorY, 
164            TextBlockAnchor anchor, float rotateX, float rotateY, double angle) {
165        Size2D d = calculateDimensions(g2);
166        float[] offsets = calculateOffsets(anchor, d.getWidth(), d.getHeight());
167        Rectangle2D bounds = new Rectangle2D.Double(anchorX + offsets[0], 
168                anchorY + offsets[1], d.getWidth(), d.getHeight());
169        Shape rotatedBounds = ShapeUtils.rotateShape(bounds, angle, rotateX, 
170                rotateY);
171        return rotatedBounds;
172    }
173    
174    /**
175     * Draws the text block at a specific location.
176     * 
177     * @param g2  the graphics device.
178     * @param x  the x-coordinate for the anchor point.
179     * @param y  the y-coordinate for the anchor point.
180     * @param anchor  the anchor point.
181     */
182    public void draw(Graphics2D g2, float x, float y, TextBlockAnchor anchor) {
183        draw(g2, x, y, anchor, 0.0f, 0.0f, 0.0);
184    }
185    
186    /**
187     * Draws the text block, aligning it with the specified anchor point and 
188     * rotating it about the specified rotation point.
189     * 
190     * @param g2  the graphics device.
191     * @param anchorX  the x-coordinate for the anchor point.
192     * @param anchorY  the y-coordinate for the anchor point.
193     * @param anchor  the point on the text block that is aligned to the 
194     *                anchor point.
195     * @param rotateX  the x-coordinate for the rotation point.
196     * @param rotateY  the x-coordinate for the rotation point.
197     * @param angle  the rotation (in radians).
198     */
199    public void draw(Graphics2D g2, float anchorX, float anchorY, 
200            TextBlockAnchor anchor, float rotateX, float rotateY, double angle) {
201    
202        Size2D d = calculateDimensions(g2);
203        float[] offsets = calculateOffsets(anchor, d.getWidth(), 
204                d.getHeight());
205        float yCursor = 0.0f;
206        for (TextLine line : this.lines) {
207            Size2D dimension = line.calculateDimensions(g2);
208            float lineOffset = 0.0f;
209            if (this.lineAlignment == HorizontalAlignment.CENTER) {
210                lineOffset = (float) (d.getWidth() - dimension.getWidth()) 
211                    / 2.0f;   
212            } else if (this.lineAlignment == HorizontalAlignment.RIGHT) {
213                lineOffset = (float) (d.getWidth() - dimension.getWidth());   
214            }
215            line.draw(g2, anchorX + offsets[0] + lineOffset, 
216                    anchorY + offsets[1] + yCursor, TextAnchor.TOP_LEFT, 
217                    rotateX, rotateY, angle);
218            yCursor = yCursor + (float) dimension.getHeight();
219        }
220        
221    }
222 
223    /**
224     * Calculates the x and y offsets required to align the text block with the
225     * specified anchor point.  This assumes that the top left of the text 
226     * block is at (0.0, 0.0).
227     * 
228     * @param anchor  the anchor position.
229     * @param width  the width of the text block.
230     * @param height  the height of the text block.
231     * 
232     * @return The offsets (float[0] = x offset, float[1] = y offset).
233     */
234    private float[] calculateOffsets(TextBlockAnchor anchor, double width, 
235            double height) {
236        float[] result = new float[2];
237        float xAdj = 0.0f;
238        float yAdj = 0.0f;
239
240        if (anchor == TextBlockAnchor.TOP_CENTER
241                || anchor == TextBlockAnchor.CENTER
242                || anchor == TextBlockAnchor.BOTTOM_CENTER) {
243                    
244            xAdj = (float) -width / 2.0f;
245            
246        } else if (anchor == TextBlockAnchor.TOP_RIGHT
247                || anchor == TextBlockAnchor.CENTER_RIGHT
248                || anchor == TextBlockAnchor.BOTTOM_RIGHT) {
249                    
250            xAdj = (float) -width;
251            
252        }
253
254        if (anchor == TextBlockAnchor.TOP_LEFT
255                || anchor == TextBlockAnchor.TOP_CENTER
256                || anchor == TextBlockAnchor.TOP_RIGHT) {
257                    
258            yAdj = 0.0f;
259            
260        } else if (anchor == TextBlockAnchor.CENTER_LEFT
261                || anchor == TextBlockAnchor.CENTER
262                || anchor == TextBlockAnchor.CENTER_RIGHT) {
263                    
264            yAdj = (float) -height / 2.0f;
265            
266        } else if (anchor == TextBlockAnchor.BOTTOM_LEFT
267                || anchor == TextBlockAnchor.BOTTOM_CENTER
268                || anchor == TextBlockAnchor.BOTTOM_RIGHT) {
269                    
270            yAdj = (float) -height;
271            
272        }
273        result[0] = xAdj;
274        result[1] = yAdj;
275        return result;
276    }   
277    
278    /**
279     * Tests this object for equality with an arbitrary object.
280     * 
281     * @param obj  the object to test against ({@code null} permitted).
282     * 
283     * @return A boolean.
284     */
285    @Override
286    public boolean equals(Object obj) {
287        if (obj == this) {
288            return true;   
289        }
290        if (obj instanceof TextBlock) {
291            TextBlock block = (TextBlock) obj;
292            return this.lines.equals(block.lines);
293        }
294        return false;
295    }
296
297    /**
298     * Returns a hash code for this object.
299     * 
300     * @return A hash code.
301     */
302    @Override
303    public int hashCode() {
304        return (this.lines != null ? this.lines.hashCode() : 0);
305    }
306}
307