001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.configuration2; 018 019import java.io.IOException; 020import java.io.Reader; 021import java.io.Writer; 022import java.util.LinkedHashMap; 023import java.util.List; 024import java.util.Map; 025import java.util.Set; 026import java.util.concurrent.atomic.AtomicInteger; 027 028import org.apache.commons.configuration2.event.ConfigurationEvent; 029import org.apache.commons.configuration2.event.EventListener; 030import org.apache.commons.configuration2.ex.ConfigurationException; 031import org.apache.commons.configuration2.ex.ConfigurationRuntimeException; 032import org.apache.commons.lang3.StringUtils; 033 034/** 035 * <p> 036 * A helper class used by {@link PropertiesConfiguration} to keep 037 * the layout of a properties file. 038 * </p> 039 * <p> 040 * Instances of this class are associated with a 041 * {@code PropertiesConfiguration} object. They are responsible for 042 * analyzing properties files and for extracting as much information about the 043 * file layout (e.g. empty lines, comments) as possible. When the properties 044 * file is written back again it should be close to the original. 045 * </p> 046 * <p> 047 * The {@code PropertiesConfigurationLayout} object associated with a 048 * {@code PropertiesConfiguration} object can be obtained using the 049 * {@code getLayout()} method of the configuration. Then the methods 050 * provided by this class can be used to alter the properties file's layout. 051 * </p> 052 * <p> 053 * Implementation note: This is a very simple implementation, which is far away 054 * from being perfect, i.e. the original layout of a properties file won't be 055 * reproduced in all cases. One limitation is that comments for multi-valued 056 * property keys are concatenated. Maybe this implementation can later be 057 * improved. 058 * </p> 059 * <p> 060 * To get an impression how this class works consider the following properties 061 * file: 062 * </p> 063 * 064 * <pre> 065 * # A demo configuration file 066 * # for Demo App 1.42 067 * 068 * # Application name 069 * AppName=Demo App 070 * 071 * # Application vendor 072 * AppVendor=DemoSoft 073 * 074 * 075 * # GUI properties 076 * # Window Color 077 * windowColors=0xFFFFFF,0x000000 078 * 079 * # Include some setting 080 * include=settings.properties 081 * # Another vendor 082 * AppVendor=TestSoft 083 * </pre> 084 * 085 * <p> 086 * For this example the following points are relevant: 087 * </p> 088 * <ul> 089 * <li>The first two lines are set as header comment. The header comment is 090 * determined by the last blanc line before the first property definition.</li> 091 * <li>For the property {@code AppName} one comment line and one 092 * leading blanc line is stored.</li> 093 * <li>For the property {@code windowColors} two comment lines and two 094 * leading blanc lines are stored.</li> 095 * <li>Include files is something this class cannot deal with well. When saving 096 * the properties configuration back, the included properties are simply 097 * contained in the original file. The comment before the include property is 098 * skipped.</li> 099 * <li>For all properties except for {@code AppVendor} the "single 100 * line" flag is set. This is relevant only for {@code windowColors}, 101 * which has multiple values defined in one line using the separator character.</li> 102 * <li>The {@code AppVendor} property appears twice. The comment lines 103 * are concatenated, so that {@code layout.getComment("AppVendor");} will 104 * result in <code>Application vendor<CR>Another vendor</code>, with 105 * <code><CR></code> meaning the line separator. In addition the 106 * "single line" flag is set to <b>false</b> for this property. When 107 * the file is saved, two property definitions will be written (in series).</li> 108 * </ul> 109 * 110 * @version $Id: PropertiesConfigurationLayout.java 1842194 2018-09-27 22:24:23Z ggregory $ 111 * @since 1.3 112 */ 113public class PropertiesConfigurationLayout implements EventListener<ConfigurationEvent> 114{ 115 /** Constant for the line break character. */ 116 private static final String CR = "\n"; 117 118 /** Constant for the default comment prefix. */ 119 private static final String COMMENT_PREFIX = "# "; 120 121 /** Stores a map with the contained layout information. */ 122 private final Map<String, PropertyLayoutData> layoutData; 123 124 /** Stores the header comment. */ 125 private String headerComment; 126 127 /** Stores the footer comment. */ 128 private String footerComment; 129 130 /** The global separator that will be used for all properties. */ 131 private String globalSeparator; 132 133 /** The line separator.*/ 134 private String lineSeparator; 135 136 /** A counter for determining nested load calls. */ 137 private final AtomicInteger loadCounter; 138 139 /** Stores the force single line flag. */ 140 private boolean forceSingleLine; 141 142 /** 143 * Creates a new, empty instance of {@code PropertiesConfigurationLayout}. 144 */ 145 public PropertiesConfigurationLayout() 146 { 147 this(null); 148 } 149 150 /** 151 * Creates a new instance of {@code PropertiesConfigurationLayout} and 152 * copies the data of the specified layout object. 153 * 154 * @param c the layout object to be copied 155 */ 156 public PropertiesConfigurationLayout(final PropertiesConfigurationLayout c) 157 { 158 loadCounter = new AtomicInteger(); 159 layoutData = new LinkedHashMap<>(); 160 161 if (c != null) 162 { 163 copyFrom(c); 164 } 165 } 166 167 /** 168 * Returns the comment for the specified property key in a canonical form. 169 * "Canonical" means that either all lines start with a comment 170 * character or none. If the {@code commentChar} parameter is <b>false</b>, 171 * all comment characters are removed, so that the result is only the plain 172 * text of the comment. Otherwise it is ensured that each line of the 173 * comment starts with a comment character. Also, line breaks in the comment 174 * are normalized to the line separator "\n". 175 * 176 * @param key the key of the property 177 * @param commentChar determines whether all lines should start with comment 178 * characters or not 179 * @return the canonical comment for this key (can be <b>null</b>) 180 */ 181 public String getCanonicalComment(final String key, final boolean commentChar) 182 { 183 return constructCanonicalComment(getComment(key), commentChar); 184 } 185 186 /** 187 * Returns the comment for the specified property key. The comment is 188 * returned as it was set (either manually by calling 189 * {@code setComment()} or when it was loaded from a properties 190 * file). No modifications are performed. 191 * 192 * @param key the key of the property 193 * @return the comment for this key (can be <b>null</b>) 194 */ 195 public String getComment(final String key) 196 { 197 return fetchLayoutData(key).getComment(); 198 } 199 200 /** 201 * Sets the comment for the specified property key. The comment (or its 202 * single lines if it is a multi-line comment) can start with a comment 203 * character. If this is the case, it will be written without changes. 204 * Otherwise a default comment character is added automatically. 205 * 206 * @param key the key of the property 207 * @param comment the comment for this key (can be <b>null</b>, then the 208 * comment will be removed) 209 */ 210 public void setComment(final String key, final String comment) 211 { 212 fetchLayoutData(key).setComment(comment); 213 } 214 215 /** 216 * Returns the number of blanc lines before this property key. If this key 217 * does not exist, 0 will be returned. 218 * 219 * @param key the property key 220 * @return the number of blanc lines before the property definition for this 221 * key 222 */ 223 public int getBlancLinesBefore(final String key) 224 { 225 return fetchLayoutData(key).getBlancLines(); 226 } 227 228 /** 229 * Sets the number of blanc lines before the given property key. This can be 230 * used for a logical grouping of properties. 231 * 232 * @param key the property key 233 * @param number the number of blanc lines to add before this property 234 * definition 235 */ 236 public void setBlancLinesBefore(final String key, final int number) 237 { 238 fetchLayoutData(key).setBlancLines(number); 239 } 240 241 /** 242 * Returns the header comment of the represented properties file in a 243 * canonical form. With the {@code commentChar} parameter it can be 244 * specified whether comment characters should be stripped or be always 245 * present. 246 * 247 * @param commentChar determines the presence of comment characters 248 * @return the header comment (can be <b>null</b>) 249 */ 250 public String getCanonicalHeaderComment(final boolean commentChar) 251 { 252 return constructCanonicalComment(getHeaderComment(), commentChar); 253 } 254 255 /** 256 * Returns the header comment of the represented properties file. This 257 * method returns the header comment exactly as it was set using 258 * {@code setHeaderComment()} or extracted from the loaded properties 259 * file. 260 * 261 * @return the header comment (can be <b>null</b>) 262 */ 263 public String getHeaderComment() 264 { 265 return headerComment; 266 } 267 268 /** 269 * Sets the header comment for the represented properties file. This comment 270 * will be output on top of the file. 271 * 272 * @param comment the comment 273 */ 274 public void setHeaderComment(final String comment) 275 { 276 headerComment = comment; 277 } 278 279 /** 280 * Returns the footer comment of the represented properties file in a 281 * canonical form. This method works like 282 * {@code getCanonicalHeaderComment()}, but reads the footer comment. 283 * 284 * @param commentChar determines the presence of comment characters 285 * @return the footer comment (can be <b>null</b>) 286 * @see #getCanonicalHeaderComment(boolean) 287 * @since 2.0 288 */ 289 public String getCanonicalFooterCooment(final boolean commentChar) 290 { 291 return constructCanonicalComment(getFooterComment(), commentChar); 292 } 293 294 /** 295 * Returns the footer comment of the represented properties file. This 296 * method returns the footer comment exactly as it was set using 297 * {@code setFooterComment()} or extracted from the loaded properties 298 * file. 299 * 300 * @return the footer comment (can be <b>null</b>) 301 * @since 2.0 302 */ 303 public String getFooterComment() 304 { 305 return footerComment; 306 } 307 308 /** 309 * Sets the footer comment for the represented properties file. This comment 310 * will be output at the bottom of the file. 311 * 312 * @param footerComment the footer comment 313 * @since 2.0 314 */ 315 public void setFooterComment(final String footerComment) 316 { 317 this.footerComment = footerComment; 318 } 319 320 /** 321 * Returns a flag whether the specified property is defined on a single 322 * line. This is meaningful only if this property has multiple values. 323 * 324 * @param key the property key 325 * @return a flag if this property is defined on a single line 326 */ 327 public boolean isSingleLine(final String key) 328 { 329 return fetchLayoutData(key).isSingleLine(); 330 } 331 332 /** 333 * Sets the "single line flag" for the specified property key. 334 * This flag is evaluated if the property has multiple values (i.e. if it is 335 * a list property). In this case, if the flag is set, all values will be 336 * written in a single property definition using the list delimiter as 337 * separator. Otherwise multiple lines will be written for this property, 338 * each line containing one property value. 339 * 340 * @param key the property key 341 * @param f the single line flag 342 */ 343 public void setSingleLine(final String key, final boolean f) 344 { 345 fetchLayoutData(key).setSingleLine(f); 346 } 347 348 /** 349 * Returns the "force single line" flag. 350 * 351 * @return the force single line flag 352 * @see #setForceSingleLine(boolean) 353 */ 354 public boolean isForceSingleLine() 355 { 356 return forceSingleLine; 357 } 358 359 /** 360 * Sets the "force single line" flag. If this flag is set, all 361 * properties with multiple values are written on single lines. This mode 362 * provides more compatibility with {@code java.lang.Properties}, 363 * which cannot deal with multiple definitions of a single property. This 364 * mode has no effect if the list delimiter parsing is disabled. 365 * 366 * @param f the force single line flag 367 */ 368 public void setForceSingleLine(final boolean f) 369 { 370 forceSingleLine = f; 371 } 372 373 /** 374 * Returns the separator for the property with the given key. 375 * 376 * @param key the property key 377 * @return the property separator for this property 378 * @since 1.7 379 */ 380 public String getSeparator(final String key) 381 { 382 return fetchLayoutData(key).getSeparator(); 383 } 384 385 /** 386 * Sets the separator to be used for the property with the given key. The 387 * separator is the string between the property key and its value. For new 388 * properties " = " is used. When a properties file is read, the 389 * layout tries to determine the separator for each property. With this 390 * method the separator can be changed. To be compatible with the properties 391 * format only the characters {@code =} and {@code :} (with or 392 * without whitespace) should be used, but this method does not enforce this 393 * - it accepts arbitrary strings. If the key refers to a property with 394 * multiple values that are written on multiple lines, this separator will 395 * be used on all lines. 396 * 397 * @param key the key for the property 398 * @param sep the separator to be used for this property 399 * @since 1.7 400 */ 401 public void setSeparator(final String key, final String sep) 402 { 403 fetchLayoutData(key).setSeparator(sep); 404 } 405 406 /** 407 * Returns the global separator. 408 * 409 * @return the global properties separator 410 * @since 1.7 411 */ 412 public String getGlobalSeparator() 413 { 414 return globalSeparator; 415 } 416 417 /** 418 * Sets the global separator for properties. With this method a separator 419 * can be set that will be used for all properties when writing the 420 * configuration. This is an easy way of determining the properties 421 * separator globally. To be compatible with the properties format only the 422 * characters {@code =} and {@code :} (with or without whitespace) 423 * should be used, but this method does not enforce this - it accepts 424 * arbitrary strings. If the global separator is set to <b>null</b>, 425 * property separators are not changed. This is the default behavior as it 426 * produces results that are closer to the original properties file. 427 * 428 * @param globalSeparator the separator to be used for all properties 429 * @since 1.7 430 */ 431 public void setGlobalSeparator(final String globalSeparator) 432 { 433 this.globalSeparator = globalSeparator; 434 } 435 436 /** 437 * Returns the line separator. 438 * 439 * @return the line separator 440 * @since 1.7 441 */ 442 public String getLineSeparator() 443 { 444 return lineSeparator; 445 } 446 447 /** 448 * Sets the line separator. When writing the properties configuration, all 449 * lines are terminated with this separator. If no separator was set, the 450 * platform-specific default line separator is used. 451 * 452 * @param lineSeparator the line separator 453 * @since 1.7 454 */ 455 public void setLineSeparator(final String lineSeparator) 456 { 457 this.lineSeparator = lineSeparator; 458 } 459 460 /** 461 * Returns a set with all property keys managed by this object. 462 * 463 * @return a set with all contained property keys 464 */ 465 public Set<String> getKeys() 466 { 467 return layoutData.keySet(); 468 } 469 470 /** 471 * Reads a properties file and stores its internal structure. The found 472 * properties will be added to the specified configuration object. 473 * 474 * @param config the associated configuration object 475 * @param in the reader to the properties file 476 * @throws ConfigurationException if an error occurs 477 */ 478 public void load(final PropertiesConfiguration config, final Reader in) 479 throws ConfigurationException 480 { 481 loadCounter.incrementAndGet(); 482 final PropertiesConfiguration.PropertiesReader reader = 483 config.getIOFactory().createPropertiesReader(in); 484 485 try 486 { 487 while (reader.nextProperty()) 488 { 489 if (config.propertyLoaded(reader.getPropertyName(), 490 reader.getPropertyValue())) 491 { 492 final boolean contained = layoutData.containsKey(reader 493 .getPropertyName()); 494 int blancLines = 0; 495 int idx = checkHeaderComment(reader.getCommentLines()); 496 while (idx < reader.getCommentLines().size() 497 && reader.getCommentLines().get(idx).length() < 1) 498 { 499 idx++; 500 blancLines++; 501 } 502 final String comment = extractComment(reader.getCommentLines(), 503 idx, reader.getCommentLines().size() - 1); 504 final PropertyLayoutData data = fetchLayoutData(reader 505 .getPropertyName()); 506 if (contained) 507 { 508 data.addComment(comment); 509 data.setSingleLine(false); 510 } 511 else 512 { 513 data.setComment(comment); 514 data.setBlancLines(blancLines); 515 data.setSeparator(reader.getPropertySeparator()); 516 } 517 } 518 } 519 520 setFooterComment(extractComment(reader.getCommentLines(), 0, reader 521 .getCommentLines().size() - 1)); 522 } 523 catch (final IOException ioex) 524 { 525 throw new ConfigurationException(ioex); 526 } 527 finally 528 { 529 loadCounter.decrementAndGet(); 530 } 531 } 532 533 /** 534 * Writes the properties file to the given writer, preserving as much of its 535 * structure as possible. 536 * 537 * @param config the associated configuration object 538 * @param out the writer 539 * @throws ConfigurationException if an error occurs 540 */ 541 public void save(final PropertiesConfiguration config, final Writer out) throws ConfigurationException 542 { 543 try 544 { 545 final PropertiesConfiguration.PropertiesWriter writer = 546 config.getIOFactory().createPropertiesWriter(out, 547 config.getListDelimiterHandler()); 548 writer.setGlobalSeparator(getGlobalSeparator()); 549 if (getLineSeparator() != null) 550 { 551 writer.setLineSeparator(getLineSeparator()); 552 } 553 554 if (headerComment != null) 555 { 556 writeComment(writer, getCanonicalHeaderComment(true)); 557 writer.writeln(null); 558 } 559 560 for (final String key : getKeys()) 561 { 562 if (config.containsKeyInternal(key)) 563 { 564 565 // Output blank lines before property 566 for (int i = 0; i < getBlancLinesBefore(key); i++) 567 { 568 writer.writeln(null); 569 } 570 571 // Output the comment 572 writeComment(writer, getCanonicalComment(key, true)); 573 574 // Output the property and its value 575 final boolean singleLine = isForceSingleLine() || isSingleLine(key); 576 writer.setCurrentSeparator(getSeparator(key)); 577 writer.writeProperty(key, config.getPropertyInternal( 578 key), singleLine); 579 } 580 } 581 582 writeComment(writer, getCanonicalFooterCooment(true)); 583 writer.flush(); 584 } 585 catch (final IOException ioex) 586 { 587 throw new ConfigurationException(ioex); 588 } 589 } 590 591 /** 592 * The event listener callback. Here event notifications of the 593 * configuration object are processed to update the layout object properly. 594 * 595 * @param event the event object 596 */ 597 @Override 598 public void onEvent(final ConfigurationEvent event) 599 { 600 if (!event.isBeforeUpdate() && loadCounter.get() == 0) 601 { 602 if (ConfigurationEvent.ADD_PROPERTY.equals(event.getEventType())) 603 { 604 final boolean contained = 605 layoutData.containsKey(event.getPropertyName()); 606 final PropertyLayoutData data = 607 fetchLayoutData(event.getPropertyName()); 608 data.setSingleLine(!contained); 609 } 610 else if (ConfigurationEvent.CLEAR_PROPERTY.equals(event 611 .getEventType())) 612 { 613 layoutData.remove(event.getPropertyName()); 614 } 615 else if (ConfigurationEvent.CLEAR.equals(event.getEventType())) 616 { 617 clear(); 618 } 619 else if (ConfigurationEvent.SET_PROPERTY.equals(event 620 .getEventType())) 621 { 622 fetchLayoutData(event.getPropertyName()); 623 } 624 } 625 } 626 627 /** 628 * Returns a layout data object for the specified key. If this is a new key, 629 * a new object is created and initialized with default values. 630 * 631 * @param key the key 632 * @return the corresponding layout data object 633 */ 634 private PropertyLayoutData fetchLayoutData(final String key) 635 { 636 if (key == null) 637 { 638 throw new IllegalArgumentException("Property key must not be null!"); 639 } 640 641 PropertyLayoutData data = layoutData.get(key); 642 if (data == null) 643 { 644 data = new PropertyLayoutData(); 645 data.setSingleLine(true); 646 layoutData.put(key, data); 647 } 648 649 return data; 650 } 651 652 /** 653 * Removes all content from this layout object. 654 */ 655 private void clear() 656 { 657 layoutData.clear(); 658 setHeaderComment(null); 659 setFooterComment(null); 660 } 661 662 /** 663 * Tests whether a line is a comment, i.e. whether it starts with a comment 664 * character. 665 * 666 * @param line the line 667 * @return a flag if this is a comment line 668 */ 669 static boolean isCommentLine(final String line) 670 { 671 return PropertiesConfiguration.isCommentLine(line); 672 } 673 674 /** 675 * Trims a comment. This method either removes all comment characters from 676 * the given string, leaving only the plain comment text or ensures that 677 * every line starts with a valid comment character. 678 * 679 * @param s the string to be processed 680 * @param comment if <b>true</b>, a comment character will always be 681 * enforced; if <b>false</b>, it will be removed 682 * @return the trimmed comment 683 */ 684 static String trimComment(final String s, final boolean comment) 685 { 686 final StringBuilder buf = new StringBuilder(s.length()); 687 int lastPos = 0; 688 int pos; 689 690 do 691 { 692 pos = s.indexOf(CR, lastPos); 693 if (pos >= 0) 694 { 695 final String line = s.substring(lastPos, pos); 696 buf.append(stripCommentChar(line, comment)).append(CR); 697 lastPos = pos + CR.length(); 698 } 699 } while (pos >= 0); 700 701 if (lastPos < s.length()) 702 { 703 buf.append(stripCommentChar(s.substring(lastPos), comment)); 704 } 705 return buf.toString(); 706 } 707 708 /** 709 * Either removes the comment character from the given comment line or 710 * ensures that the line starts with a comment character. 711 * 712 * @param s the comment line 713 * @param comment if <b>true</b>, a comment character will always be 714 * enforced; if <b>false</b>, it will be removed 715 * @return the line without comment character 716 */ 717 static String stripCommentChar(final String s, final boolean comment) 718 { 719 if (StringUtils.isBlank(s) || (isCommentLine(s) == comment)) 720 { 721 return s; 722 } 723 if (!comment) 724 { 725 int pos = 0; 726 // find first comment character 727 while (PropertiesConfiguration.COMMENT_CHARS.indexOf(s 728 .charAt(pos)) < 0) 729 { 730 pos++; 731 } 732 733 // Remove leading spaces 734 pos++; 735 while (pos < s.length() 736 && Character.isWhitespace(s.charAt(pos))) 737 { 738 pos++; 739 } 740 741 return (pos < s.length()) ? s.substring(pos) 742 : StringUtils.EMPTY; 743 } 744 return COMMENT_PREFIX + s; 745 } 746 747 /** 748 * Extracts a comment string from the given range of the specified comment 749 * lines. The single lines are added using a line feed as separator. 750 * 751 * @param commentLines a list with comment lines 752 * @param from the start index 753 * @param to the end index (inclusive) 754 * @return the comment string (<b>null</b> if it is undefined) 755 */ 756 private String extractComment(final List<String> commentLines, final int from, final int to) 757 { 758 if (to < from) 759 { 760 return null; 761 } 762 final StringBuilder buf = new StringBuilder(commentLines.get(from)); 763 for (int i = from + 1; i <= to; i++) 764 { 765 buf.append(CR); 766 buf.append(commentLines.get(i)); 767 } 768 return buf.toString(); 769 } 770 771 /** 772 * Checks if parts of the passed in comment can be used as header comment. 773 * This method checks whether a header comment can be defined (i.e. whether 774 * this is the first comment in the loaded file). If this is the case, it is 775 * searched for the latest blanc line. This line will mark the end of the 776 * header comment. The return value is the index of the first line in the 777 * passed in list, which does not belong to the header comment. 778 * 779 * @param commentLines the comment lines 780 * @return the index of the next line after the header comment 781 */ 782 private int checkHeaderComment(final List<String> commentLines) 783 { 784 if (loadCounter.get() == 1 && layoutData.isEmpty()) 785 { 786 // This is the first comment. Search for blanc lines. 787 int index = commentLines.size() - 1; 788 while (index >= 0 789 && commentLines.get(index).length() > 0) 790 { 791 index--; 792 } 793 if (getHeaderComment() == null) 794 { 795 setHeaderComment(extractComment(commentLines, 0, index - 1)); 796 } 797 return index + 1; 798 } 799 return 0; 800 } 801 802 /** 803 * Copies the data from the given layout object. 804 * 805 * @param c the layout object to copy 806 */ 807 private void copyFrom(final PropertiesConfigurationLayout c) 808 { 809 for (final String key : c.getKeys()) 810 { 811 final PropertyLayoutData data = c.layoutData.get(key); 812 layoutData.put(key, data.clone()); 813 } 814 815 setHeaderComment(c.getHeaderComment()); 816 setFooterComment(c.getFooterComment()); 817 } 818 819 /** 820 * Helper method for writing a comment line. This method ensures that the 821 * correct line separator is used if the comment spans multiple lines. 822 * 823 * @param writer the writer 824 * @param comment the comment to write 825 * @throws IOException if an IO error occurs 826 */ 827 private static void writeComment( 828 final PropertiesConfiguration.PropertiesWriter writer, final String comment) 829 throws IOException 830 { 831 if (comment != null) 832 { 833 writer.writeln(StringUtils.replace(comment, CR, writer 834 .getLineSeparator())); 835 } 836 } 837 838 /** 839 * Helper method for generating a comment string. Depending on the boolean 840 * argument the resulting string either has no comment characters or a 841 * leading comment character at each line. 842 * 843 * @param comment the comment string to be processed 844 * @param commentChar determines the presence of comment characters 845 * @return the canonical comment string (can be <b>null</b>) 846 */ 847 private static String constructCanonicalComment(final String comment, 848 final boolean commentChar) 849 { 850 return (comment == null) ? null : trimComment(comment, commentChar); 851 } 852 853 /** 854 * A helper class for storing all layout related information for a 855 * configuration property. 856 */ 857 static class PropertyLayoutData implements Cloneable 858 { 859 /** Stores the comment for the property. */ 860 private StringBuffer comment; 861 862 /** The separator to be used for this property. */ 863 private String separator; 864 865 /** Stores the number of blanc lines before this property. */ 866 private int blancLines; 867 868 /** Stores the single line property. */ 869 private boolean singleLine; 870 871 /** 872 * Creates a new instance of {@code PropertyLayoutData}. 873 */ 874 public PropertyLayoutData() 875 { 876 singleLine = true; 877 separator = PropertiesConfiguration.DEFAULT_SEPARATOR; 878 } 879 880 /** 881 * Returns the number of blanc lines before this property. 882 * 883 * @return the number of blanc lines before this property 884 */ 885 public int getBlancLines() 886 { 887 return blancLines; 888 } 889 890 /** 891 * Sets the number of properties before this property. 892 * 893 * @param blancLines the number of properties before this property 894 */ 895 public void setBlancLines(final int blancLines) 896 { 897 this.blancLines = blancLines; 898 } 899 900 /** 901 * Returns the single line flag. 902 * 903 * @return the single line flag 904 */ 905 public boolean isSingleLine() 906 { 907 return singleLine; 908 } 909 910 /** 911 * Sets the single line flag. 912 * 913 * @param singleLine the single line flag 914 */ 915 public void setSingleLine(final boolean singleLine) 916 { 917 this.singleLine = singleLine; 918 } 919 920 /** 921 * Adds a comment for this property. If already a comment exists, the 922 * new comment is added (separated by a newline). 923 * 924 * @param s the comment to add 925 */ 926 public void addComment(final String s) 927 { 928 if (s != null) 929 { 930 if (comment == null) 931 { 932 comment = new StringBuffer(s); 933 } 934 else 935 { 936 comment.append(CR).append(s); 937 } 938 } 939 } 940 941 /** 942 * Sets the comment for this property. 943 * 944 * @param s the new comment (can be <b>null</b>) 945 */ 946 public void setComment(final String s) 947 { 948 if (s == null) 949 { 950 comment = null; 951 } 952 else 953 { 954 comment = new StringBuffer(s); 955 } 956 } 957 958 /** 959 * Returns the comment for this property. The comment is returned as it 960 * is, without processing of comment characters. 961 * 962 * @return the comment (can be <b>null</b>) 963 */ 964 public String getComment() 965 { 966 return (comment == null) ? null : comment.toString(); 967 } 968 969 /** 970 * Returns the separator that was used for this property. 971 * 972 * @return the property separator 973 */ 974 public String getSeparator() 975 { 976 return separator; 977 } 978 979 /** 980 * Sets the separator to be used for the represented property. 981 * 982 * @param separator the property separator 983 */ 984 public void setSeparator(final String separator) 985 { 986 this.separator = separator; 987 } 988 989 /** 990 * Creates a copy of this object. 991 * 992 * @return the copy 993 */ 994 @Override 995 public PropertyLayoutData clone() 996 { 997 try 998 { 999 final PropertyLayoutData copy = (PropertyLayoutData) super.clone(); 1000 if (comment != null) 1001 { 1002 // must copy string buffer, too 1003 copy.comment = new StringBuffer(getComment()); 1004 } 1005 return copy; 1006 } 1007 catch (final CloneNotSupportedException cnex) 1008 { 1009 // This cannot happen! 1010 throw new ConfigurationRuntimeException(cnex); 1011 } 1012 } 1013 } 1014}