J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1997-2001 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | package javax.swing.text; |
| 26 | |
| 27 | import java.util.Vector; |
| 28 | import java.io.Serializable; |
| 29 | import javax.swing.undo.*; |
| 30 | import javax.swing.SwingUtilities; |
| 31 | |
| 32 | /** |
| 33 | * An implementation of the AbstractDocument.Content interface that is |
| 34 | * a brute force implementation that is useful for relatively small |
| 35 | * documents and/or debugging. It manages the character content |
| 36 | * as a simple character array. It is also quite inefficient. |
| 37 | * <p> |
| 38 | * It is generally recommended that the gap buffer or piece table |
| 39 | * implementations be used instead. This buffer does not scale up |
| 40 | * to large sizes. |
| 41 | * <p> |
| 42 | * <strong>Warning:</strong> |
| 43 | * Serialized objects of this class will not be compatible with |
| 44 | * future Swing releases. The current serialization support is |
| 45 | * appropriate for short term storage or RMI between applications running |
| 46 | * the same version of Swing. As of 1.4, support for long term storage |
| 47 | * of all JavaBeans<sup><font size="-2">TM</font></sup> |
| 48 | * has been added to the <code>java.beans</code> package. |
| 49 | * Please see {@link java.beans.XMLEncoder}. |
| 50 | * |
| 51 | * @author Timothy Prinzing |
| 52 | */ |
| 53 | public final class StringContent implements AbstractDocument.Content, Serializable { |
| 54 | |
| 55 | /** |
| 56 | * Creates a new StringContent object. Initial size defaults to 10. |
| 57 | */ |
| 58 | public StringContent() { |
| 59 | this(10); |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Creates a new StringContent object, with the initial |
| 64 | * size specified. If the length is < 1, a size of 1 is used. |
| 65 | * |
| 66 | * @param initialLength the initial size |
| 67 | */ |
| 68 | public StringContent(int initialLength) { |
| 69 | if (initialLength < 1) { |
| 70 | initialLength = 1; |
| 71 | } |
| 72 | data = new char[initialLength]; |
| 73 | data[0] = '\n'; |
| 74 | count = 1; |
| 75 | } |
| 76 | |
| 77 | /** |
| 78 | * Returns the length of the content. |
| 79 | * |
| 80 | * @return the length >= 1 |
| 81 | * @see AbstractDocument.Content#length |
| 82 | */ |
| 83 | public int length() { |
| 84 | return count; |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Inserts a string into the content. |
| 89 | * |
| 90 | * @param where the starting position >= 0 && < length() |
| 91 | * @param str the non-null string to insert |
| 92 | * @return an UndoableEdit object for undoing |
| 93 | * @exception BadLocationException if the specified position is invalid |
| 94 | * @see AbstractDocument.Content#insertString |
| 95 | */ |
| 96 | public UndoableEdit insertString(int where, String str) throws BadLocationException { |
| 97 | if (where >= count || where < 0) { |
| 98 | throw new BadLocationException("Invalid location", count); |
| 99 | } |
| 100 | char[] chars = str.toCharArray(); |
| 101 | replace(where, 0, chars, 0, chars.length); |
| 102 | if (marks != null) { |
| 103 | updateMarksForInsert(where, str.length()); |
| 104 | } |
| 105 | return new InsertUndo(where, str.length()); |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Removes part of the content. where + nitems must be < length(). |
| 110 | * |
| 111 | * @param where the starting position >= 0 |
| 112 | * @param nitems the number of characters to remove >= 0 |
| 113 | * @return an UndoableEdit object for undoing |
| 114 | * @exception BadLocationException if the specified position is invalid |
| 115 | * @see AbstractDocument.Content#remove |
| 116 | */ |
| 117 | public UndoableEdit remove(int where, int nitems) throws BadLocationException { |
| 118 | if (where + nitems >= count) { |
| 119 | throw new BadLocationException("Invalid range", count); |
| 120 | } |
| 121 | String removedString = getString(where, nitems); |
| 122 | UndoableEdit edit = new RemoveUndo(where, removedString); |
| 123 | replace(where, nitems, empty, 0, 0); |
| 124 | if (marks != null) { |
| 125 | updateMarksForRemove(where, nitems); |
| 126 | } |
| 127 | return edit; |
| 128 | |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Retrieves a portion of the content. where + len must be <= length(). |
| 133 | * |
| 134 | * @param where the starting position >= 0 |
| 135 | * @param len the length to retrieve >= 0 |
| 136 | * @return a string representing the content; may be empty |
| 137 | * @exception BadLocationException if the specified position is invalid |
| 138 | * @see AbstractDocument.Content#getString |
| 139 | */ |
| 140 | public String getString(int where, int len) throws BadLocationException { |
| 141 | if (where + len > count) { |
| 142 | throw new BadLocationException("Invalid range", count); |
| 143 | } |
| 144 | return new String(data, where, len); |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Retrieves a portion of the content. where + len must be <= length() |
| 149 | * |
| 150 | * @param where the starting position >= 0 |
| 151 | * @param len the number of characters to retrieve >= 0 |
| 152 | * @param chars the Segment object to return the characters in |
| 153 | * @exception BadLocationException if the specified position is invalid |
| 154 | * @see AbstractDocument.Content#getChars |
| 155 | */ |
| 156 | public void getChars(int where, int len, Segment chars) throws BadLocationException { |
| 157 | if (where + len > count) { |
| 158 | throw new BadLocationException("Invalid location", count); |
| 159 | } |
| 160 | chars.array = data; |
| 161 | chars.offset = where; |
| 162 | chars.count = len; |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * Creates a position within the content that will |
| 167 | * track change as the content is mutated. |
| 168 | * |
| 169 | * @param offset the offset to create a position for >= 0 |
| 170 | * @return the position |
| 171 | * @exception BadLocationException if the specified position is invalid |
| 172 | */ |
| 173 | public Position createPosition(int offset) throws BadLocationException { |
| 174 | // some small documents won't have any sticky positions |
| 175 | // at all, so the buffer is created lazily. |
| 176 | if (marks == null) { |
| 177 | marks = new Vector(); |
| 178 | } |
| 179 | return new StickyPosition(offset); |
| 180 | } |
| 181 | |
| 182 | // --- local methods --------------------------------------- |
| 183 | |
| 184 | /** |
| 185 | * Replaces some of the characters in the array |
| 186 | * @param offset offset into the array to start the replace |
| 187 | * @param length number of characters to remove |
| 188 | * @param replArray replacement array |
| 189 | * @param replOffset offset into the replacement array |
| 190 | * @param replLength number of character to use from the |
| 191 | * replacement array. |
| 192 | */ |
| 193 | void replace(int offset, int length, |
| 194 | char[] replArray, int replOffset, int replLength) { |
| 195 | int delta = replLength - length; |
| 196 | int src = offset + length; |
| 197 | int nmove = count - src; |
| 198 | int dest = src + delta; |
| 199 | if ((count + delta) >= data.length) { |
| 200 | // need to grow the array |
| 201 | int newLength = Math.max(2*data.length, count + delta); |
| 202 | char[] newData = new char[newLength]; |
| 203 | System.arraycopy(data, 0, newData, 0, offset); |
| 204 | System.arraycopy(replArray, replOffset, newData, offset, replLength); |
| 205 | System.arraycopy(data, src, newData, dest, nmove); |
| 206 | data = newData; |
| 207 | } else { |
| 208 | // patch the existing array |
| 209 | System.arraycopy(data, src, data, dest, nmove); |
| 210 | System.arraycopy(replArray, replOffset, data, offset, replLength); |
| 211 | } |
| 212 | count = count + delta; |
| 213 | } |
| 214 | |
| 215 | void resize(int ncount) { |
| 216 | char[] ndata = new char[ncount]; |
| 217 | System.arraycopy(data, 0, ndata, 0, Math.min(ncount, count)); |
| 218 | data = ndata; |
| 219 | } |
| 220 | |
| 221 | synchronized void updateMarksForInsert(int offset, int length) { |
| 222 | if (offset == 0) { |
| 223 | // zero is a special case where we update only |
| 224 | // marks after it. |
| 225 | offset = 1; |
| 226 | } |
| 227 | int n = marks.size(); |
| 228 | for (int i = 0; i < n; i++) { |
| 229 | PosRec mark = (PosRec) marks.elementAt(i); |
| 230 | if (mark.unused) { |
| 231 | // this record is no longer used, get rid of it |
| 232 | marks.removeElementAt(i); |
| 233 | i -= 1; |
| 234 | n -= 1; |
| 235 | } else if (mark.offset >= offset) { |
| 236 | mark.offset += length; |
| 237 | } |
| 238 | } |
| 239 | } |
| 240 | |
| 241 | synchronized void updateMarksForRemove(int offset, int length) { |
| 242 | int n = marks.size(); |
| 243 | for (int i = 0; i < n; i++) { |
| 244 | PosRec mark = (PosRec) marks.elementAt(i); |
| 245 | if (mark.unused) { |
| 246 | // this record is no longer used, get rid of it |
| 247 | marks.removeElementAt(i); |
| 248 | i -= 1; |
| 249 | n -= 1; |
| 250 | } else if (mark.offset >= (offset + length)) { |
| 251 | mark.offset -= length; |
| 252 | } else if (mark.offset >= offset) { |
| 253 | mark.offset = offset; |
| 254 | } |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * Returns a Vector containing instances of UndoPosRef for the |
| 260 | * Positions in the range |
| 261 | * <code>offset</code> to <code>offset</code> + <code>length</code>. |
| 262 | * If <code>v</code> is not null the matching Positions are placed in |
| 263 | * there. The vector with the resulting Positions are returned. |
| 264 | * <p> |
| 265 | * This is meant for internal usage, and is generally not of interest |
| 266 | * to subclasses. |
| 267 | * |
| 268 | * @param v the Vector to use, with a new one created on null |
| 269 | * @param offset the starting offset >= 0 |
| 270 | * @param length the length >= 0 |
| 271 | * @return the set of instances |
| 272 | */ |
| 273 | protected Vector getPositionsInRange(Vector v, int offset, |
| 274 | int length) { |
| 275 | int n = marks.size(); |
| 276 | int end = offset + length; |
| 277 | Vector placeIn = (v == null) ? new Vector() : v; |
| 278 | for (int i = 0; i < n; i++) { |
| 279 | PosRec mark = (PosRec) marks.elementAt(i); |
| 280 | if (mark.unused) { |
| 281 | // this record is no longer used, get rid of it |
| 282 | marks.removeElementAt(i); |
| 283 | i -= 1; |
| 284 | n -= 1; |
| 285 | } else if(mark.offset >= offset && mark.offset <= end) |
| 286 | placeIn.addElement(new UndoPosRef(mark)); |
| 287 | } |
| 288 | return placeIn; |
| 289 | } |
| 290 | |
| 291 | /** |
| 292 | * Resets the location for all the UndoPosRef instances |
| 293 | * in <code>positions</code>. |
| 294 | * <p> |
| 295 | * This is meant for internal usage, and is generally not of interest |
| 296 | * to subclasses. |
| 297 | * |
| 298 | * @param positions the positions of the instances |
| 299 | */ |
| 300 | protected void updateUndoPositions(Vector positions) { |
| 301 | for(int counter = positions.size() - 1; counter >= 0; counter--) { |
| 302 | UndoPosRef ref = (UndoPosRef)positions.elementAt(counter); |
| 303 | // Check if the Position is still valid. |
| 304 | if(ref.rec.unused) { |
| 305 | positions.removeElementAt(counter); |
| 306 | } |
| 307 | else |
| 308 | ref.resetLocation(); |
| 309 | } |
| 310 | } |
| 311 | |
| 312 | private static final char[] empty = new char[0]; |
| 313 | private char[] data; |
| 314 | private int count; |
| 315 | transient Vector marks; |
| 316 | |
| 317 | /** |
| 318 | * holds the data for a mark... separately from |
| 319 | * the real mark so that the real mark can be |
| 320 | * collected if there are no more references to |
| 321 | * it.... the update table holds only a reference |
| 322 | * to this grungy thing. |
| 323 | */ |
| 324 | final class PosRec { |
| 325 | |
| 326 | PosRec(int offset) { |
| 327 | this.offset = offset; |
| 328 | } |
| 329 | |
| 330 | int offset; |
| 331 | boolean unused; |
| 332 | } |
| 333 | |
| 334 | /** |
| 335 | * This really wants to be a weak reference but |
| 336 | * in 1.1 we don't have a 100% pure solution for |
| 337 | * this... so this class trys to hack a solution |
| 338 | * to causing the marks to be collected. |
| 339 | */ |
| 340 | final class StickyPosition implements Position { |
| 341 | |
| 342 | StickyPosition(int offset) { |
| 343 | rec = new PosRec(offset); |
| 344 | marks.addElement(rec); |
| 345 | } |
| 346 | |
| 347 | public int getOffset() { |
| 348 | return rec.offset; |
| 349 | } |
| 350 | |
| 351 | protected void finalize() throws Throwable { |
| 352 | // schedule the record to be removed later |
| 353 | // on another thread. |
| 354 | rec.unused = true; |
| 355 | } |
| 356 | |
| 357 | public String toString() { |
| 358 | return Integer.toString(getOffset()); |
| 359 | } |
| 360 | |
| 361 | PosRec rec; |
| 362 | } |
| 363 | |
| 364 | /** |
| 365 | * Used to hold a reference to a Position that is being reset as the |
| 366 | * result of removing from the content. |
| 367 | */ |
| 368 | final class UndoPosRef { |
| 369 | UndoPosRef(PosRec rec) { |
| 370 | this.rec = rec; |
| 371 | this.undoLocation = rec.offset; |
| 372 | } |
| 373 | |
| 374 | /** |
| 375 | * Resets the location of the Position to the offset when the |
| 376 | * receiver was instantiated. |
| 377 | */ |
| 378 | protected void resetLocation() { |
| 379 | rec.offset = undoLocation; |
| 380 | } |
| 381 | |
| 382 | /** Location to reset to when resetLocatino is invoked. */ |
| 383 | protected int undoLocation; |
| 384 | /** Position to reset offset. */ |
| 385 | protected PosRec rec; |
| 386 | } |
| 387 | |
| 388 | /** |
| 389 | * UnoableEdit created for inserts. |
| 390 | */ |
| 391 | class InsertUndo extends AbstractUndoableEdit { |
| 392 | protected InsertUndo(int offset, int length) { |
| 393 | super(); |
| 394 | this.offset = offset; |
| 395 | this.length = length; |
| 396 | } |
| 397 | |
| 398 | public void undo() throws CannotUndoException { |
| 399 | super.undo(); |
| 400 | try { |
| 401 | synchronized(StringContent.this) { |
| 402 | // Get the Positions in the range being removed. |
| 403 | if(marks != null) |
| 404 | posRefs = getPositionsInRange(null, offset, length); |
| 405 | string = getString(offset, length); |
| 406 | remove(offset, length); |
| 407 | } |
| 408 | } catch (BadLocationException bl) { |
| 409 | throw new CannotUndoException(); |
| 410 | } |
| 411 | } |
| 412 | |
| 413 | public void redo() throws CannotRedoException { |
| 414 | super.redo(); |
| 415 | try { |
| 416 | synchronized(StringContent.this) { |
| 417 | insertString(offset, string); |
| 418 | string = null; |
| 419 | // Update the Positions that were in the range removed. |
| 420 | if(posRefs != null) { |
| 421 | updateUndoPositions(posRefs); |
| 422 | posRefs = null; |
| 423 | } |
| 424 | } |
| 425 | } catch (BadLocationException bl) { |
| 426 | throw new CannotRedoException(); |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | // Where the string goes. |
| 431 | protected int offset; |
| 432 | // Length of the string. |
| 433 | protected int length; |
| 434 | // The string that was inserted. To cut down on space needed this |
| 435 | // will only be valid after an undo. |
| 436 | protected String string; |
| 437 | // An array of instances of UndoPosRef for the Positions in the |
| 438 | // range that was removed, valid after undo. |
| 439 | protected Vector posRefs; |
| 440 | } |
| 441 | |
| 442 | |
| 443 | /** |
| 444 | * UndoableEdit created for removes. |
| 445 | */ |
| 446 | class RemoveUndo extends AbstractUndoableEdit { |
| 447 | protected RemoveUndo(int offset, String string) { |
| 448 | super(); |
| 449 | this.offset = offset; |
| 450 | this.string = string; |
| 451 | this.length = string.length(); |
| 452 | if(marks != null) |
| 453 | posRefs = getPositionsInRange(null, offset, length); |
| 454 | } |
| 455 | |
| 456 | public void undo() throws CannotUndoException { |
| 457 | super.undo(); |
| 458 | try { |
| 459 | synchronized(StringContent.this) { |
| 460 | insertString(offset, string); |
| 461 | // Update the Positions that were in the range removed. |
| 462 | if(posRefs != null) { |
| 463 | updateUndoPositions(posRefs); |
| 464 | posRefs = null; |
| 465 | } |
| 466 | string = null; |
| 467 | } |
| 468 | } catch (BadLocationException bl) { |
| 469 | throw new CannotUndoException(); |
| 470 | } |
| 471 | } |
| 472 | |
| 473 | public void redo() throws CannotRedoException { |
| 474 | super.redo(); |
| 475 | try { |
| 476 | synchronized(StringContent.this) { |
| 477 | string = getString(offset, length); |
| 478 | // Get the Positions in the range being removed. |
| 479 | if(marks != null) |
| 480 | posRefs = getPositionsInRange(null, offset, length); |
| 481 | remove(offset, length); |
| 482 | } |
| 483 | } catch (BadLocationException bl) { |
| 484 | throw new CannotRedoException(); |
| 485 | } |
| 486 | } |
| 487 | |
| 488 | // Where the string goes. |
| 489 | protected int offset; |
| 490 | // Length of the string. |
| 491 | protected int length; |
| 492 | // The string that was inserted. This will be null after an undo. |
| 493 | protected String string; |
| 494 | // An array of instances of UndoPosRef for the Positions in the |
| 495 | // range that was removed, valid before undo. |
| 496 | protected Vector posRefs; |
| 497 | } |
| 498 | } |