1 /*
2 * Copyright (c) 2003, 2008, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javax.swing;
27
28 import javax.swing.table.*;
29 import java.awt.*;
30 import java.awt.print.*;
31 import java.awt.geom.*;
32 import java.text.MessageFormat;
33
34 /**
35 * An implementation of <code>Printable</code> for printing
36 * <code>JTable</code>s.
37 * <p>
38 * This implementation spreads table rows naturally in sequence
39 * across multiple pages, fitting as many rows as possible per page.
40 * The distribution of columns, on the other hand, is controlled by a
41 * printing mode parameter passed to the constructor. When
42 * <code>JTable.PrintMode.NORMAL</code> is used, the implementation
43 * handles columns in a similar manner to how it handles rows, spreading them
44 * across multiple pages (in an order consistent with the table's
45 * <code>ComponentOrientation</code>).
46 * When <code>JTable.PrintMode.FIT_WIDTH</code> is given, the implementation
47 * scales the output smaller if necessary, to ensure that all columns fit on
48 * the page. (Note that width and height are scaled equally, ensuring that the
49 * aspect ratio remains the same).
50 * <p>
51 * The portion of table printed on each page is headed by the
52 * appropriate section of the table's <code>JTableHeader</code>.
53 * <p>
54 * Header and footer text can be added to the output by providing
55 * <code>MessageFormat</code> instances to the constructor. The
56 * printing code requests Strings from the formats by calling
57 * their <code>format</code> method with a single parameter:
58 * an <code>Object</code> array containing a single element of type
59 * <code>Integer</code>, representing the current page number.
60 * <p>
61 * There are certain circumstances where this <code>Printable</code>
62 * cannot fit items appropriately, resulting in clipped output.
63 * These are:
64 * <ul>
65 * <li>In any mode, when the header or footer text is too wide to
66 * fit completely in the printable area. The implementation
67 * prints as much of the text as possible starting from the beginning,
68 * as determined by the table's <code>ComponentOrientation</code>.
69 * <li>In any mode, when a row is too tall to fit in the
70 * printable area. The upper most portion of the row
71 * is printed and no lower border is shown.
72 * <li>In <code>JTable.PrintMode.NORMAL</code> when a column
73 * is too wide to fit in the printable area. The center of the
74 * column is printed and no left and right borders are shown.
75 * </ul>
76 * <p>
77 * It is entirely valid for a developer to wrap this <code>Printable</code>
78 * inside another in order to create complex reports and documents. They may
79 * even request that different pages be rendered into different sized
80 * printable areas. The implementation was designed to handle this by
81 * performing most of its calculations on the fly. However, providing different
82 * sizes works best when <code>JTable.PrintMode.FIT_WIDTH</code> is used, or
83 * when only the printable width is changed between pages. This is because when
84 * it is printing a set of rows in <code>JTable.PrintMode.NORMAL</code> and the
85 * implementation determines a need to distribute columns across pages,
86 * it assumes that all of those rows will fit on each subsequent page needed
87 * to fit the columns.
88 * <p>
89 * It is the responsibility of the developer to ensure that the table is not
90 * modified in any way after this <code>Printable</code> is created (invalid
91 * modifications include changes in: size, renderers, or underlying data).
92 * The behavior of this <code>Printable</code> is undefined if the table is
93 * changed at any time after creation.
94 *
95 * @author Shannon Hickey
96 */
97 class TablePrintable implements Printable {
98
99 /** The table to print. */
100 private JTable table;
101
102 /** For quick reference to the table's header. */
103 private JTableHeader header;
104
105 /** For quick reference to the table's column model. */
106 private TableColumnModel colModel;
107
108 /** To save multiple calculations of total column width. */
109 private int totalColWidth;
110
111 /** The printing mode of this printable. */
112 private JTable.PrintMode printMode;
113
114 /** Provides the header text for the table. */
115 private MessageFormat headerFormat;
116
117 /** Provides the footer text for the table. */
118 private MessageFormat footerFormat;
119
120 /** The most recent page index asked to print. */
121 private int last = -1;
122
123 /** The next row to print. */
124 private int row = 0;
125
126 /** The next column to print. */
127 private int col = 0;
128
129 /** Used to store an area of the table to be printed. */
130 private final Rectangle clip = new Rectangle(0, 0, 0, 0);
131
132 /** Used to store an area of the table's header to be printed. */
133 private final Rectangle hclip = new Rectangle(0, 0, 0, 0);
134
135 /** Saves the creation of multiple rectangles. */
136 private final Rectangle tempRect = new Rectangle(0, 0, 0, 0);
137
138 /** Vertical space to leave between table and header/footer text. */
139 private static final int H_F_SPACE = 8;
140
141 /** Font size for the header text. */
142 private static final float HEADER_FONT_SIZE = 18.0f;
143
144 /** Font size for the footer text. */
145 private static final float FOOTER_FONT_SIZE = 12.0f;
146
147 /** The font to use in rendering header text. */
148 private Font headerFont;
149
150 /** The font to use in rendering footer text. */
151 private Font footerFont;
152
153 /**
154 * Create a new <code>TablePrintable</code> for the given
155 * <code>JTable</code>. Header and footer text can be specified using the
156 * two <code>MessageFormat</code> parameters. When called upon to provide
157 * a String, each format is given the current page number.
158 *
159 * @param table the table to print
160 * @param printMode the printing mode for this printable
161 * @param headerFormat a <code>MessageFormat</code> specifying the text to
162 * be used in printing a header, or null for none
163 * @param footerFormat a <code>MessageFormat</code> specifying the text to
164 * be used in printing a footer, or null for none
165 * @throws IllegalArgumentException if passed an invalid print mode
166 */
167 public TablePrintable(JTable table,
168 JTable.PrintMode printMode,
169 MessageFormat headerFormat,
170 MessageFormat footerFormat) {
171
172 this.table = table;
173
174 header = table.getTableHeader();
175 colModel = table.getColumnModel();
176 totalColWidth = colModel.getTotalColumnWidth();
177
178 if (header != null) {
179 // the header clip height can be set once since it's unchanging
180 hclip.height = header.getHeight();
181 }
182
183 this.printMode = printMode;
184
185 this.headerFormat = headerFormat;
186 this.footerFormat = footerFormat;
187
188 // derive the header and footer font from the table's font
189 headerFont = table.getFont().deriveFont(Font.BOLD,
190 HEADER_FONT_SIZE);
191 footerFont = table.getFont().deriveFont(Font.PLAIN,
192 FOOTER_FONT_SIZE);
193 }
194
195 /**
196 * Prints the specified page of the table into the given {@link Graphics}
197 * context, in the specified format.
198 *
199 * @param graphics the context into which the page is drawn
200 * @param pageFormat the size and orientation of the page being drawn
201 * @param pageIndex the zero based index of the page to be drawn
202 * @return PAGE_EXISTS if the page is rendered successfully, or
203 * NO_SUCH_PAGE if a non-existent page index is specified
204 * @throws PrinterException if an error causes printing to be aborted
205 */
206 public int print(Graphics graphics, PageFormat pageFormat, int pageIndex)
207 throws PrinterException {
208
209 // for easy access to these values
210 final int imgWidth = (int)pageFormat.getImageableWidth();
211 final int imgHeight = (int)pageFormat.getImageableHeight();
212
213 if (imgWidth <= 0) {
214 throw new PrinterException("Width of printable area is too small.");
215 }
216
217 // to pass the page number when formatting the header and footer text
218 Object[] pageNumber = new Object[]{Integer.valueOf(pageIndex + 1)};
219
220 // fetch the formatted header text, if any
221 String headerText = null;
222 if (headerFormat != null) {
223 headerText = headerFormat.format(pageNumber);
224 }
225
226 // fetch the formatted footer text, if any
227 String footerText = null;
228 if (footerFormat != null) {
229 footerText = footerFormat.format(pageNumber);
230 }
231
232 // to store the bounds of the header and footer text
233 Rectangle2D hRect = null;
234 Rectangle2D fRect = null;
235
236 // the amount of vertical space needed for the header and footer text
237 int headerTextSpace = 0;
238 int footerTextSpace = 0;
239
240 // the amount of vertical space available for printing the table
241 int availableSpace = imgHeight;
242
243 // if there's header text, find out how much space is needed for it
244 // and subtract that from the available space
245 if (headerText != null) {
246 graphics.setFont(headerFont);
247 hRect = graphics.getFontMetrics().getStringBounds(headerText,
248 graphics);
249
250 headerTextSpace = (int)Math.ceil(hRect.getHeight());
251 availableSpace -= headerTextSpace + H_F_SPACE;
252 }
253
254 // if there's footer text, find out how much space is needed for it
255 // and subtract that from the available space
256 if (footerText != null) {
257 graphics.setFont(footerFont);
258 fRect = graphics.getFontMetrics().getStringBounds(footerText,
259 graphics);
260
261 footerTextSpace = (int)Math.ceil(fRect.getHeight());
262 availableSpace -= footerTextSpace + H_F_SPACE;
263 }
264
265 if (availableSpace <= 0) {
266 throw new PrinterException("Height of printable area is too small.");
267 }
268
269 // depending on the print mode, we may need a scale factor to
270 // fit the table's entire width on the page
271 double sf = 1.0D;
272 if (printMode == JTable.PrintMode.FIT_WIDTH &&
273 totalColWidth > imgWidth) {
274
275 // if not, we would have thrown an acception previously
276 assert imgWidth > 0;
277
278 // it must be, according to the if-condition, since imgWidth > 0
279 assert totalColWidth > 1;
280
281 sf = (double)imgWidth / (double)totalColWidth;
282 }
283
284 // dictated by the previous two assertions
285 assert sf > 0;
286
287 // This is in a loop for two reasons:
288 // First, it allows us to catch up in case we're called starting
289 // with a non-zero pageIndex. Second, we know that we can be called
290 // for the same page multiple times. The condition of this while
291 // loop acts as a check, ensuring that we don't attempt to do the
292 // calculations again when we are called subsequent times for the
293 // same page.
294 while (last < pageIndex) {
295 // if we are finished all columns in all rows
296 if (row >= table.getRowCount() && col == 0) {
297 return NO_SUCH_PAGE;
298 }
299
300 // rather than multiplying every row and column by the scale factor
301 // in findNextClip, just pass a width and height that have already
302 // been divided by it
303 int scaledWidth = (int)(imgWidth / sf);
304 int scaledHeight = (int)((availableSpace - hclip.height) / sf);
305
306 // calculate the area of the table to be printed for this page
307 findNextClip(scaledWidth, scaledHeight);
308
309 last++;
310 }
311
312 // create a copy of the graphics so we don't affect the one given to us
313 Graphics2D g2d = (Graphics2D)graphics.create();
314
315 // translate into the co-ordinate system of the pageFormat
316 g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
317
318 // to save and store the transform
319 AffineTransform oldTrans;
320
321 // if there's footer text, print it at the bottom of the imageable area
322 if (footerText != null) {
323 oldTrans = g2d.getTransform();
324
325 g2d.translate(0, imgHeight - footerTextSpace);
326
327 printText(g2d, footerText, fRect, footerFont, imgWidth);
328
329 g2d.setTransform(oldTrans);
330 }
331
332 // if there's header text, print it at the top of the imageable area
333 // and then translate downwards
334 if (headerText != null) {
335 printText(g2d, headerText, hRect, headerFont, imgWidth);
336
337 g2d.translate(0, headerTextSpace + H_F_SPACE);
338 }
339
340 // constrain the table output to the available space
341 tempRect.x = 0;
342 tempRect.y = 0;
343 tempRect.width = imgWidth;
344 tempRect.height = availableSpace;
345 g2d.clip(tempRect);
346
347 // if we have a scale factor, scale the graphics object to fit
348 // the entire width
349 if (sf != 1.0D) {
350 g2d.scale(sf, sf);
351
352 // otherwise, ensure that the current portion of the table is
353 // centered horizontally
354 } else {
355 int diff = (imgWidth - clip.width) / 2;
356 g2d.translate(diff, 0);
357 }
358
359 // store the old transform and clip for later restoration
360 oldTrans = g2d.getTransform();
361 Shape oldClip = g2d.getClip();
362
363 // if there's a table header, print the current section and
364 // then translate downwards
365 if (header != null) {
366 hclip.x = clip.x;
367 hclip.width = clip.width;
368
369 g2d.translate(-hclip.x, 0);
370 g2d.clip(hclip);
371 header.print(g2d);
372
373 // restore the original transform and clip
374 g2d.setTransform(oldTrans);
375 g2d.setClip(oldClip);
376
377 // translate downwards
378 g2d.translate(0, hclip.height);
379 }
380
381 // print the current section of the table
382 g2d.translate(-clip.x, -clip.y);
383 g2d.clip(clip);
384 table.print(g2d);
385
386 // restore the original transform and clip
387 g2d.setTransform(oldTrans);
388 g2d.setClip(oldClip);
389
390 // draw a box around the table
391 g2d.setColor(Color.BLACK);
392 g2d.drawRect(0, 0, clip.width, hclip.height + clip.height);
393
394 // dispose the graphics copy
395 g2d.dispose();
396
397 return PAGE_EXISTS;
398 }
399
400 /**
401 * A helper method that encapsulates common code for rendering the
402 * header and footer text.
403 *
404 * @param g2d the graphics to draw into
405 * @param text the text to draw, non null
406 * @param rect the bounding rectangle for this text,
407 * as calculated at the given font, non null
408 * @param font the font to draw the text in, non null
409 * @param imgWidth the width of the area to draw into
410 */
411 private void printText(Graphics2D g2d,
412 String text,
413 Rectangle2D rect,
414 Font font,
415 int imgWidth) {
416
417 int tx;
418
419 // if the text is small enough to fit, center it
420 if (rect.getWidth() < imgWidth) {
421 tx = (int)((imgWidth - rect.getWidth()) / 2);
422
423 // otherwise, if the table is LTR, ensure the left side of
424 // the text shows; the right can be clipped
425 } else if (table.getComponentOrientation().isLeftToRight()) {
426 tx = 0;
427
428 // otherwise, ensure the right side of the text shows
429 } else {
430 tx = -(int)(Math.ceil(rect.getWidth()) - imgWidth);
431 }
432
433 int ty = (int)Math.ceil(Math.abs(rect.getY()));
434 g2d.setColor(Color.BLACK);
435 g2d.setFont(font);
436 g2d.drawString(text, tx, ty);
437 }
438
439 /**
440 * Calculate the area of the table to be printed for
441 * the next page. This should only be called if there
442 * are rows and columns left to print.
443 *
444 * To avoid an infinite loop in printing, this will
445 * always put at least one cell on each page.
446 *
447 * @param pw the width of the area to print in
448 * @param ph the height of the area to print in
449 */
450 private void findNextClip(int pw, int ph) {
451 final boolean ltr = table.getComponentOrientation().isLeftToRight();
452
453 // if we're ready to start a new set of rows
454 if (col == 0) {
455 if (ltr) {
456 // adjust clip to the left of the first column
457 clip.x = 0;
458 } else {
459 // adjust clip to the right of the first column
460 clip.x = totalColWidth;
461 }
462
463 // adjust clip to the top of the next set of rows
464 clip.y += clip.height;
465
466 // adjust clip width and height to be zero
467 clip.width = 0;
468 clip.height = 0;
469
470 // fit as many rows as possible, and at least one
471 int rowCount = table.getRowCount();
472 int rowHeight = table.getRowHeight(row);
473 do {
474 clip.height += rowHeight;
475
476 if (++row >= rowCount) {
477 break;
478 }
479
480 rowHeight = table.getRowHeight(row);
481 } while (clip.height + rowHeight <= ph);
482 }
483
484 // we can short-circuit for JTable.PrintMode.FIT_WIDTH since
485 // we'll always fit all columns on the page
486 if (printMode == JTable.PrintMode.FIT_WIDTH) {
487 clip.x = 0;
488 clip.width = totalColWidth;
489 return;
490 }
491
492 if (ltr) {
493 // adjust clip to the left of the next set of columns
494 clip.x += clip.width;
495 }
496
497 // adjust clip width to be zero
498 clip.width = 0;
499
500 // fit as many columns as possible, and at least one
501 int colCount = table.getColumnCount();
502 int colWidth = colModel.getColumn(col).getWidth();
503 do {
504 clip.width += colWidth;
505 if (!ltr) {
506 clip.x -= colWidth;
507 }
508
509 if (++col >= colCount) {
510 // reset col to 0 to indicate we're finished all columns
511 col = 0;
512
513 break;
514 }
515
516 colWidth = colModel.getColumn(col).getWidth();
517 } while (clip.width + colWidth <= pw);
518
519 }
520
521 }