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37
40
41 import java.applet.Applet  ;
42 import java.awt.*;
43 import java.awt.event.*;
44 import java.io.*;
45 import java.lang.*;
46 import java.net.*;
47
48 public class SpreadSheet
49 extends Applet
50 implements MouseListener, KeyListener {
51 String title;
52 Font titleFont;
53 Color cellColor;
54 Color inputColor;
55 int cellWidth = 100;
56 int cellHeight = 15;
57 int titleHeight = 15;
58 int rowLabelWidth = 15;
59 Font inputFont;
60 boolean isStopped = false;
61 boolean fullUpdate = true;
62 int rows;
63 int columns;
64 int currentKey = -1;
65 int selectedRow = -1;
66 int selectedColumn = -1;
67 SpreadSheetInput inputArea;
68 Cell cells[][];
69 Cell current = null;
70
71 public synchronized void init() {
72 String rs;
73
74 cellColor = Color.white;
75 inputColor = new Color(100, 100, 225);
76 inputFont = new Font("Monospaced", Font.PLAIN, 10);
77 titleFont = new Font("Monospaced", Font.BOLD, 12);
78 title = getParameter("title");
79 if (title == null) {
80 title = "Spreadsheet";
81 }
82 rs = getParameter("rows");
83 if (rs == null) {
84 rows = 9;
85 } else {
86 rows = Integer.parseInt(rs);
87 }
88 rs = getParameter("columns");
89 if (rs == null) {
90 columns = 5;
91 } else {
92 columns = Integer.parseInt(rs);
93 }
94 cells = new Cell[rows][columns];
95 char l[] = new char[1];
96 for (int i=0; i < rows; i++) {
97 for (int j=0; j < columns; j++) {
98
99 cells[i][j] = new Cell(this,
100 Color.lightGray,
101 Color.black,
102 cellColor,
103 cellWidth - 2,
104 cellHeight - 2);
105 l[0] = (char)((int)'a' + j);
106 rs = getParameter("" + new String (l) + (i+1));
107 if (rs != null) {
108 cells[i][j].setUnparsedValue(rs);
109 }
110 }
111 }
112
113 Dimension d = getSize();
114 inputArea = new SpreadSheetInput(null, this, d.width - 2, cellHeight - 1,
115 inputColor, Color.white);
116 resize(columns * cellWidth + rowLabelWidth,
117 (rows + 3) * cellHeight + titleHeight);
118 addMouseListener(this);
119 addKeyListener(this);
120 }
121
122 public void setCurrentValue(float val) {
123 if (selectedRow == -1 || selectedColumn == -1) {
124 return;
125 }
126 cells[selectedRow][selectedColumn].setValue(val);
127 repaint();
128 }
129
130 public void stop() {
131 isStopped = true;
132 }
133
134 public void start() {
135 isStopped = false;
136 }
137
138 public void destroy() {
139 for (int i=0; i < rows; i++) {
140 for (int j=0; j < columns; j++) {
141 if (cells[i][j].type == Cell.URL) {
142 cells[i][j].updaterThread.stop();
143 }
144 }
145 }
146 }
147
148 public void setCurrentValue(int type, String val) {
149 if (selectedRow == -1 || selectedColumn == -1) {
150 return;
151 }
152 cells[selectedRow][selectedColumn].setValue(type, val);
153 repaint();
154 }
155
156 public void update(Graphics g) {
157 if (! fullUpdate) {
158 int cx, cy;
159
160 g.setFont(titleFont);
161 for (int i=0; i < rows; i++) {
162 for (int j=0; j < columns; j++) {
163 if (cells[i][j].needRedisplay) {
164 cx = (j * cellWidth) + 2 + rowLabelWidth;
165 cy = ((i+1) * cellHeight) + 2 + titleHeight;
166 cells[i][j].paint(g, cx, cy);
167 }
168 }
169 }
170 } else {
171 paint(g);
172 fullUpdate = false;
173 }
174 }
175
176 public void recalculate() {
177 int i,j;
178
179 for (i=0; i < rows; i++) {
181 for (j=0; j < columns; j++) {
182 if (cells[i][j] != null && cells[i][j].type == Cell.FORMULA) {
183 cells[i][j].setRawValue(evaluateFormula(cells[i][j].parseRoot));
184 cells[i][j].needRedisplay = true;
185 }
186 }
187 }
188 repaint();
189 }
190
191 public float evaluateFormula(Node n) {
192 float val = 0.0f;
193
194 if (n == null) {
197 return val;
199 }
200 switch (n.type) {
201 case Node.OP:
202 val = evaluateFormula(n.left);
203 switch (n.op) {
204 case '+':
205 val += evaluateFormula(n.right);
206 break;
207 case '*':
208 val *= evaluateFormula(n.right);
209 break;
210 case '-':
211 val -= evaluateFormula(n.right);
212 break;
213 case '/':
214 val /= evaluateFormula(n.right);
215 break;
216 }
217 break;
218 case Node.VALUE:
219 return n.value;
221 case Node.CELL:
222 if (n == null) {
223 } else {
225 if (cells[n.row][n.column] == null) {
226 } else {
228 return cells[n.row][n.column].value;
230 }
231 }
232 }
233
234 return val;
236 }
237
238 public synchronized void paint(Graphics g) {
239 int i, j;
240 int cx, cy;
241 char l[] = new char[1];
242
243
244 Dimension d = getSize();
245
246 g.setFont(titleFont);
247 i = g.getFontMetrics().stringWidth(title);
248 g.drawString((title == null) ? "Spreadsheet" : title,
249 (d.width - i) / 2, 12);
250 g.setColor(inputColor);
251 g.fillRect(0, cellHeight, d.width, cellHeight);
252 g.setFont(titleFont);
253 for (i=0; i < rows+1; i++) {
254 cy = (i+2) * cellHeight;
255 g.setColor(getBackground());
256 g.draw3DRect(0, cy, d.width, 2, true);
257 if (i < rows) {
258 g.setColor(Color.red);
259 g.drawString("" + (i+1), 2, cy + 12);
260 }
261 }
262
263 g.setColor(Color.red);
264 cy = (rows+3) * cellHeight + (cellHeight / 2);
265 for (i=0; i < columns; i++) {
266 cx = i * cellWidth;
267 g.setColor(getBackground());
268 g.draw3DRect(cx + rowLabelWidth,
269 2 * cellHeight, 1, d.height, true);
270 if (i < columns) {
271 g.setColor(Color.red);
272 l[0] = (char)((int)'A' + i);
273 g.drawString(new String (l),
274 cx + rowLabelWidth + (cellWidth / 2),
275 cy);
276 }
277 }
278
279 for (i=0; i < rows; i++) {
280 for (j=0; j < columns; j++) {
281 cx = (j * cellWidth) + 2 + rowLabelWidth;
282 cy = ((i+1) * cellHeight) + 2 + titleHeight;
283 if (cells[i][j] != null) {
284 cells[i][j].paint(g, cx, cy);
285 }
286 }
287 }
288
289 g.setColor(getBackground());
290 g.draw3DRect(0, titleHeight,
291 d.width,
292 d.height - titleHeight,
293 false);
294 inputArea.paint(g, 1, titleHeight + 1);
295 }
296
297
299 public void mouseClicked(MouseEvent e)
300 {}
301
302 public void mousePressed(MouseEvent e)
303 {
304 int x = e.getX();
305 int y = e.getY();
306 Cell cell;
307 if (y < (titleHeight + cellHeight)) {
308 selectedRow = -1;
309 if (y <= titleHeight && current != null) {
310 current.deselect();
311 current = null;
312 }
313 e.consume();
314 }
315 if (x < rowLabelWidth) {
316 selectedRow = -1;
317 if (current != null) {
318 current.deselect();
319 current = null;
320 }
321 e.consume();
322
323 }
324 selectedRow = ((y - cellHeight - titleHeight) / cellHeight);
325 selectedColumn = (x - rowLabelWidth) / cellWidth;
326 if (selectedRow > rows ||
327 selectedColumn >= columns) {
328 selectedRow = -1;
329 if (current != null) {
330 current.deselect();
331 current = null;
332 }
333 } else {
334 if (selectedRow >= rows) {
335 selectedRow = -1;
336 if (current != null) {
337 current.deselect();
338 current = null;
339 }
340 e.consume();
341 }
342 if (selectedRow != -1) {
343 cell = cells[selectedRow][selectedColumn];
344 inputArea.setText(new String (cell.getPrintString()));
345 if (current != null) {
346 current.deselect();
347 }
348 current = cell;
349 current.select();
350 requestFocus();
351 fullUpdate = true;
352 repaint();
353 }
354 e.consume();
355 }
356 }
357
358 public void mouseReleased(MouseEvent e)
359 {}
360
361 public void mouseEntered(MouseEvent e)
362 {}
363
364 public void mouseExited(MouseEvent e)
365 {}
366
367 public void keyPressed(KeyEvent e)
368 {
369 }
370
371 public void keyTyped(KeyEvent e) {
372 fullUpdate=true;
373 inputArea.processKey(e);
374 e.consume();
375 }
376
377 public void keyReleased(KeyEvent e)
378 {}
379
380 public String getAppletInfo() {
381 return "Title: SpreadSheet \nAuthor: Sami Shaio \nA simple spread sheet.";
382 }
383
384 public String [][] getParameterInfo() {
385 String [][] info = {
386 {"title", "string", "The title of the spread sheet. Default is 'Spreadsheet'"},
387 {"rows", "int", "The number of rows. Default is 9."},
388 {"columns", "int", "The number of columns. Default is 5."}
389 };
390 return info;
391 }
392
393
394 }
395
396 class CellUpdater extends Thread {
397 Cell target;
398 InputStream dataStream = null;
399 StreamTokenizer tokenStream;
400
401 public CellUpdater(Cell c) {
402 super("cell updater");
403 target = c;
404 }
405
406 public void run() {
407 try {
408 dataStream = new URL(target.app.getDocumentBase(),
409 target.getValueString()).openStream();
410 tokenStream = new StreamTokenizer(new BufferedReader(new InputStreamReader(dataStream)));
411 tokenStream.eolIsSignificant(false);
412
413 while (true) {
414 switch (tokenStream.nextToken()) {
415 case StreamTokenizer.TT_EOF:
416 dataStream.close();
417 return;
418 default:
419 break;
420 case StreamTokenizer.TT_NUMBER:
421 target.setTransientValue((float)tokenStream.nval);
422 if (! target.app.isStopped && ! target.paused) {
423 target.app.repaint();
424 }
425 break;
426 }
427 try {
428 Thread.sleep(2000);
429 } catch (InterruptedException e) {
430 break;
431 }
432 }
433 } catch (IOException e) {
434 return;
435 }
436 }
437 }
438
439 class Cell {
440 public static final int VALUE = 0;
441 public static final int LABEL = 1;
442 public static final int URL = 2;
443 public static final int FORMULA = 3;
444
445 Node parseRoot;
446 boolean needRedisplay;
447 boolean selected = false;
448 boolean transientValue = false;
449 public int type = Cell.VALUE;
450 String valueString = "";
451 String printString = "v";
452 float value;
453 Color bgColor;
454 Color fgColor;
455 Color highlightColor;
456 int width;
457 int height;
458 SpreadSheet app;
459 CellUpdater updaterThread;
460 boolean paused = false;
461
462 public Cell(SpreadSheet app,
463 Color bgColor,
464 Color fgColor,
465 Color highlightColor,
466 int width,
467 int height) {
468 this.app = app;
469 this.bgColor = bgColor;
470 this.fgColor = fgColor;
471 this.highlightColor = highlightColor;
472 this.width = width;
473 this.height = height;
474 needRedisplay = true;
475 }
476
477 public void setRawValue(float f) {
478 valueString = Float.toString(f);
479 value = f;
480 }
481 public void setValue(float f) {
482 setRawValue(f);
483 printString = "v" + valueString;
484 type = Cell.VALUE;
485 paused = false;
486 app.recalculate();
487 needRedisplay = true;
488 }
489
490 public void setTransientValue(float f) {
491 transientValue = true;
492 value = f;
493 needRedisplay = true;
494 app.recalculate();
495 }
496
497 public void setUnparsedValue(String s) {
498 switch (s.charAt(0)) {
499 case 'v':
500 setValue(Cell.VALUE, s.substring(1));
501 break;
502 case 'f':
503 setValue(Cell.FORMULA, s.substring(1));
504 break;
505 case 'l':
506 setValue(Cell.LABEL, s.substring(1));
507 break;
508 case 'u':
509 setValue(Cell.URL, s.substring(1));
510 break;
511 }
512 }
513
514
525 public String parseFormula(String formula, Node node) {
526 String subformula;
527 String restFormula;
528 float value;
529 int length = formula.length();
530 Node left;
531 Node right;
532 char op;
533
534 if (formula == null) {
535 return null;
536 }
537 subformula = parseValue(formula, node);
538 if (subformula == null || subformula.length() == 0) {
540 return null;
542 }
543 if (subformula == formula) {
544 return formula;
546 }
547
548 switch (op = subformula.charAt(0)) {
550 case 0:
551 return null;
553 case ')':
554 return subformula;
556 case '+':
557 case '*':
558 case '-':
559 case '/':
560 restFormula = subformula.substring(1);
561 subformula = parseValue(restFormula, right=new Node());
562 if (subformula != restFormula) {
564 left = new Node(node);
566 node.left = left;
567 node.right = right;
568 node.op = op;
569 node.type = Node.OP;
570 return subformula;
572 } else {
573 return formula;
575 }
576 default:
577 return formula;
579 }
580 }
581
582 public String parseValue(String formula, Node node) {
583 char c = formula.charAt(0);
584 String subformula;
585 String restFormula;
586 float value;
587 int row;
588 int column;
589
590 restFormula = formula;
592 if (c == '(') {
593 restFormula = formula.substring(1);
595 subformula = parseFormula(restFormula, node);
596 if (subformula == null ||
598 subformula.length() == restFormula.length()) {
599 return formula;
601 } else if (! (subformula.charAt(0) == ')')) {
602 return formula;
604 }
605 restFormula = subformula;
606 } else if (c >= '0' && c <= '9') {
607 int i;
608
609 for (i=0; i < formula.length(); i++) {
611 c = formula.charAt(i);
612 if ((c < '0' || c > '9') && c != '.') {
613 break;
614 }
615 }
616 try {
617 value = Float.valueOf(formula.substring(0, i)).floatValue();
618 } catch (NumberFormatException e) {
619 return formula;
621 }
622 node.type = Node.VALUE;
623 node.value = value;
624 restFormula = formula.substring(i);
626 return restFormula;
629 } else if (c >= 'A' && c <= 'Z') {
630 int i;
631
632 column = c - 'A';
633 restFormula = formula.substring(1);
634 for (i=0; i < restFormula.length(); i++) {
635 c = restFormula.charAt(i);
636 if (c < '0' || c > '9') {
637 break;
638 }
639 }
640 row = Float.valueOf(restFormula.substring(0, i)).intValue();
641 node.row = row - 1;
643 node.column = column;
644 node.type = Node.CELL;
645 if (i == restFormula.length()) {
647 restFormula = null;
648 } else {
649 restFormula = restFormula.substring(i);
650 if (restFormula.charAt(0) == 0) {
651 return null;
652 }
653 }
654 }
655
656 return restFormula;
657 }
658
659
660 public void setValue(int type, String s) {
661 paused = false;
662 if (this.type == Cell.URL) {
663 updaterThread.stop();
664 updaterThread = null;
665 }
666
667 valueString = new String (s);
668 this.type = type;
669 needRedisplay = true;
670 switch (type) {
671 case Cell.VALUE:
672 setValue(Float.valueOf(s).floatValue());
673 break;
674 case Cell.LABEL:
675 printString = "l" + valueString;
676 break;
677 case Cell.URL:
678 printString = "u" + valueString;
679 updaterThread = new CellUpdater(this);
680 updaterThread.start();
681 break;
682 case Cell.FORMULA:
683 parseFormula(valueString, parseRoot = new Node());
684 printString = "f" + valueString;
685 break;
686 }
687 app.recalculate();
688 }
689
690 public String getValueString() {
691 return valueString;
692 }
693
694 public String getPrintString() {
695 return printString;
696 }
697
698 public void select() {
699 selected = true;
700 paused = true;
701 }
702 public void deselect() {
703 selected = false;
704 paused = false;
705 needRedisplay = true;
706 app.repaint();
707 }
708 public void paint(Graphics g, int x, int y) {
709 if (selected) {
710 g.setColor(highlightColor);
711 } else {
712 g.setColor(bgColor);
713 }
714 g.fillRect(x, y, width - 1, height);
715 if (valueString != null) {
716 switch (type) {
717 case Cell.VALUE:
718 case Cell.LABEL:
719 g.setColor(fgColor);
720 break;
721 case Cell.FORMULA:
722 g.setColor(Color.red);
723 break;
724 case Cell.URL:
725 g.setColor(Color.blue);
726 break;
727 }
728 if (transientValue){
729 g.drawString("" + value, x, y + (height / 2) + 5);
730 } else {
731 if (valueString.length() > 14) {
732 g.drawString(valueString.substring(0, 14),
733 x, y + (height / 2) + 5);
734 } else {
735 g.drawString(valueString, x, y + (height / 2) + 5);
736 }
737 }
738 }
739 needRedisplay = false;
740 }
741 }
742
743 class Node {
744 public static final int OP = 0;
745 public static final int VALUE = 1;
746 public static final int CELL = 2;
747
748 int type;
749 Node left;
750 Node right;
751 int row;
752 int column;
753 float value;
754 char op;
755
756 public Node() {
757 left = null;
758 right = null;
759 value = 0;
760 row = -1;
761 column = -1;
762 op = 0;
763 type = Node.VALUE;
764 }
765 public Node(Node n) {
766 left = n.left;
767 right = n.right;
768 value = n.value;
769 row = n.row;
770 column = n.column;
771 op = n.op;
772 type = n.type;
773 }
774 public void indent(int ind) {
775 for (int i = 0; i < ind; i++) {
776 System.out.print(" ");
777 }
778 }
779 public void print(int indentLevel) {
780 char l[] = new char[1];
781 indent(indentLevel);
782 System.out.println("NODE type=" + type);
783 indent(indentLevel);
784 switch (type) {
785 case Node.VALUE:
786 System.out.println(" value=" + value);
787 break;
788 case Node.CELL:
789 l[0] = (char)((int)'A' + column);
790 System.out.println(" cell=" + new String (l) + (row+1));
791 break;
792 case Node.OP:
793 System.out.println(" op=" + op);
794 left.print(indentLevel + 3);
795 right.print(indentLevel + 3);
796 break;
797 }
798 }
799 }
800
801 class InputField {
802 int maxchars = 50;
803 int cursorPos = 0;
804 Applet app;
805 String sval;
806 char buffer[];
807 int nChars;
808 int width;
809 int height;
810 Color bgColor;
811 Color fgColor;
812
813 public InputField(String initValue, Applet app, int width, int height,
814 Color bgColor, Color fgColor) {
815 this.width = width;
816 this.height = height;
817 this.bgColor = bgColor;
818 this.fgColor = fgColor;
819 this.app = app;
820 buffer = new char[maxchars];
821 nChars = 0;
822 if (initValue != null) {
823 initValue.getChars(0, initValue.length(), this.buffer, 0);
824 nChars = initValue.length();
825 }
826 sval = initValue;
827 }
828
829 public void setText(String val) {
830 int i;
831
832 for (i=0; i < maxchars; i++) {
833 buffer[i] = 0;
834 }
835 if (val == null) {
836 sval = "";
837 } else {
838 sval = val;
839 }
840 nChars = sval.length();
841 sval.getChars(0, sval.length(), buffer, 0);
842 }
843
844 public String getValue() {
845 return sval;
846 }
847
848 public void paint(Graphics g, int x, int y) {
849 g.setColor(bgColor);
850 g.fillRect(x, y, width, height);
851 if (sval != null) {
852 g.setColor(fgColor);
853 g.drawString(sval, x, y + (height / 2) + 3);
854 }
855 }
856
857 public void processKey(KeyEvent e) {
858 char ch = e.getKeyChar();
859 switch (ch) {
860 case '\b': if (nChars > 0) {
862 nChars--;
863 sval = new String (buffer, 0, nChars);
864 }
865 break;
866 case '\n': selected();
868 break;
869 default:
870 if (nChars < maxchars && ch >= '0') {
871 buffer[nChars++] = ch;
872 sval = new String (buffer, 0, nChars);
873 }
874 }
875 app.repaint();
876 }
877
878 public void keyReleased(KeyEvent e) {
879 }
880
881 public void selected() {
882 }
883 }
884
885 class SpreadSheetInput
886 extends InputField {
887
888 public SpreadSheetInput(String initValue,
889 SpreadSheet app,
890 int width,
891 int height,
892 Color bgColor,
893 Color fgColor) {
894 super(initValue, app, width, height, bgColor, fgColor);
895 }
896
897 public void selected() {
898 float f;
899 sval = ("".equals(sval)) ? "v":sval;
900 switch (sval.charAt(0)) {
901 case 'v':
902 String s= sval.substring(1);
903 try {
904 int i;
905 for (i = 0; i < s.length(); i++) {
906 char c = s.charAt(i);
907 if (c < '0' || c > '9')
908 break;
909 }
910 s = s.substring(0, i);
911 f = Float.valueOf(s).floatValue();
912 ((SpreadSheet)app).setCurrentValue(f);
913 } catch (NumberFormatException e) {
914 System.out.println("Not a float: '" + s + "'");
915 }
916 break;
917 case 'l':
918 ((SpreadSheet)app).setCurrentValue(Cell.LABEL, sval.substring(1));
919 break;
920 case 'u':
921 ((SpreadSheet)app).setCurrentValue(Cell.URL, sval.substring(1));
922 break;
923 case 'f':
924 ((SpreadSheet)app).setCurrentValue(Cell.FORMULA, sval.substring(1));
925 break;
926 }
927 }
928 }
929 |
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