Coverage Report - org.apache.commons.configuration.PropertiesConfigurationLayout
 
Classes in this File Line Coverage Branch Coverage Complexity
PropertiesConfigurationLayout
99%
143/145
100%
35/35
2,444
PropertiesConfigurationLayout$PropertyLayoutData
96%
23/24
100%
5/5
2,444
 
 1  
 /*
 2  
  * Licensed to the Apache Software Foundation (ASF) under one or more
 3  
  * contributor license agreements.  See the NOTICE file distributed with
 4  
  * this work for additional information regarding copyright ownership.
 5  
  * The ASF licenses this file to You under the Apache License, Version 2.0
 6  
  * (the "License"); you may not use this file except in compliance with
 7  
  * the License.  You may obtain a copy of the License at
 8  
  *
 9  
  *     http://www.apache.org/licenses/LICENSE-2.0
 10  
  *
 11  
  * Unless required by applicable law or agreed to in writing, software
 12  
  * distributed under the License is distributed on an "AS IS" BASIS,
 13  
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 14  
  * See the License for the specific language governing permissions and
 15  
  * limitations under the License.
 16  
  */
 17  
 package org.apache.commons.configuration;
 18  
 
 19  
 import java.io.IOException;
 20  
 import java.io.Reader;
 21  
 import java.io.Writer;
 22  
 import java.util.Iterator;
 23  
 import java.util.List;
 24  
 import java.util.Map;
 25  
 import java.util.Set;
 26  
 
 27  
 import org.apache.commons.collections.map.LinkedMap;
 28  
 import org.apache.commons.configuration.event.ConfigurationEvent;
 29  
 import org.apache.commons.configuration.event.ConfigurationListener;
 30  
 import org.apache.commons.lang.StringUtils;
 31  
 
 32  
 /**
 33  
  * <p>
 34  
  * A helper class used by <code>{@link PropertiesConfiguration}</code> to keep
 35  
  * the layout of a properties file.
 36  
  * </p>
 37  
  * <p>
 38  
  * Instances of this class are associated with a
 39  
  * <code>PropertiesConfiguration</code> object. They are responsible for
 40  
  * analyzing properties files and for extracting as much information about the
 41  
  * file layout (e.g. empty lines, comments) as possible. When the properties
 42  
  * file is written back again it should be close to the original.
 43  
  * </p>
 44  
  * <p>
 45  
  * The <code>PropertiesConfigurationLayout</code> object associated with a
 46  
  * <code>PropertiesConfiguration</code> object can be obtained using the
 47  
  * <code>getLayout()</code> method of the configuration. Then the methods
 48  
  * provided by this class can be used to alter the properties file's layout.
 49  
  * </p>
 50  
  * <p>
 51  
  * Implementation note: This is a very simple implementation, which is far away
 52  
  * from being perfect, i.e. the original layout of a properties file won't be
 53  
  * reproduced in all cases. One limitation is that comments for multi-valued
 54  
  * property keys are concatenated. Maybe this implementation can later be
 55  
  * improved.
 56  
  * </p>
 57  
  * <p>
 58  
  * To get an impression how this class works consider the following properties
 59  
  * file:
 60  
  * </p>
 61  
  * <p>
 62  
  *
 63  
  * <pre>
 64  
  * # A demo configuration file
 65  
  * # for Demo App 1.42
 66  
  *
 67  
  * # Application name
 68  
  * AppName=Demo App
 69  
  *
 70  
  * # Application vendor
 71  
  * AppVendor=DemoSoft
 72  
  *
 73  
  *
 74  
  * # GUI properties
 75  
  * # Window Color
 76  
  * windowColors=0xFFFFFF,0x000000
 77  
  *
 78  
  * # Include some setting
 79  
  * include=settings.properties
 80  
  * # Another vendor
 81  
  * AppVendor=TestSoft
 82  
  * </pre>
 83  
  *
 84  
  * </p>
 85  
  * <p>
 86  
  * For this example the following points are relevant:
 87  
  * </p>
 88  
  * <p>
 89  
  * <ul>
 90  
  * <li>The first two lines are set as header comment. The header comment is
 91  
  * determined by the last blanc line before the first property definition.</li>
 92  
  * <li>For the property <code>AppName</code> one comment line and one
 93  
  * leading blanc line is stored.</li>
 94  
  * <li>For the property <code>windowColors</code> two comment lines and two
 95  
  * leading blanc lines are stored.</li>
 96  
  * <li>Include files is something this class cannot deal with well. When saving
 97  
  * the properties configuration back, the included properties are simply
 98  
  * contained in the original file. The comment before the include property is
 99  
  * skipped.</li>
 100  
  * <li>For all properties except for <code>AppVendor</code> the &quot;single
 101  
  * line&quot; flag is set. This is relevant only for <code>windowColors</code>,
 102  
  * which has multiple values defined in one line using the separator character.</li>
 103  
  * <li>The <code>AppVendor</code> property appears twice. The comment lines
 104  
  * are concatenated, so that <code>layout.getComment("AppVendor");</code> will
 105  
  * result in <code>Application vendor&lt;CR&gt;Another vendor</code>, whith
 106  
  * <code>&lt;CR&gt;</code> meaning the line separator. In addition the
 107  
  * &quot;single line&quot; flag is set to <b>false</b> for this property. When
 108  
  * the file is saved, two property definitions will be written (in series).</li>
 109  
  * </ul>
 110  
  * </p>
 111  
  *
 112  
  * @author <a
 113  
  * href="http://jakarta.apache.org/commons/configuration/team-list.html">Commons
 114  
  * Configuration team</a>
 115  
  * @version $Id: PropertiesConfigurationLayout.java 439648 2006-09-02 20:42:10Z oheger $
 116  
  * @since 1.3
 117  
  */
 118  813
 public class PropertiesConfigurationLayout implements ConfigurationListener
 119  
 {
 120  
     /** Constant for the line break character. */
 121  20
     private static final String CR = System.getProperty("line.separator");
 122  
 
 123  
     /** Constant for the default comment prefix. */
 124  
     private static final String COMMENT_PREFIX = "# ";
 125  
 
 126  
     /** Stores the associated configuration object. */
 127  
     private PropertiesConfiguration configuration;
 128  
 
 129  
     /** Stores a map with the contained layout information. */
 130  
     private Map layoutData;
 131  
 
 132  
     /** Stores the header comment. */
 133  
     private String headerComment;
 134  
 
 135  
     /** A counter for determining nested load calls. */
 136  
     private int loadCounter;
 137  
 
 138  
     /** Stores the force single line flag. */
 139  
     private boolean forceSingleLine;
 140  
 
 141  
     /**
 142  
      * Creates a new instance of <code>PropertiesConfigurationLayout</code>
 143  
      * and initializes it with the associated configuration object.
 144  
      *
 145  
      * @param config the configuration (must not be <b>null</b>)
 146  
      */
 147  
     public PropertiesConfigurationLayout(PropertiesConfiguration config)
 148  
     {
 149  417
         this(config, null);
 150  416
     }
 151  
 
 152  
     /**
 153  
      * Creates a new instance of <code>PropertiesConfigurationLayout</code>
 154  
      * and initializes it with the given configuration object. The data of the
 155  
      * specified layout object is copied.
 156  
      *
 157  
      * @param config the configuration (must not be <b>null</b>)
 158  
      * @param c the layout object to be copied
 159  
      */
 160  
     public PropertiesConfigurationLayout(PropertiesConfiguration config,
 161  
             PropertiesConfigurationLayout c)
 162  423
     {
 163  423
         if (config == null)
 164  
         {
 165  1
             throw new IllegalArgumentException(
 166  
                     "Configuration must not be null!");
 167  
         }
 168  422
         configuration = config;
 169  422
         layoutData = new LinkedMap();
 170  422
         config.addConfigurationListener(this);
 171  
 
 172  422
         if (c != null)
 173  
         {
 174  6
             copyFrom(c);
 175  
         }
 176  422
     }
 177  
 
 178  
     /**
 179  
      * Returns the associated configuration object.
 180  
      *
 181  
      * @return the associated configuration
 182  
      */
 183  
     public PropertiesConfiguration getConfiguration()
 184  
     {
 185  21730
         return configuration;
 186  
     }
 187  
 
 188  
     /**
 189  
      * Returns the comment for the specified property key in a cononical form.
 190  
      * &quot;Canonical&quot; means that either all lines start with a comment
 191  
      * character or none. The <code>commentChar</code> parameter is <b>false</b>,
 192  
      * all comment characters are removed, so that the result is only the plain
 193  
      * text of the comment. Otherwise it is ensured that each line of the
 194  
      * comment starts with a comment character.
 195  
      *
 196  
      * @param key the key of the property
 197  
      * @param commentChar determines whether all lines should start with comment
 198  
      * characters or not
 199  
      * @return the canonical comment for this key (can be <b>null</b>)
 200  
      */
 201  
     public String getCanonicalComment(String key, boolean commentChar)
 202  
     {
 203  40
         String comment = getComment(key);
 204  40
         if (comment == null)
 205  
         {
 206  1
             return null;
 207  
         }
 208  
         else
 209  
         {
 210  39
             return trimComment(comment, commentChar);
 211  
         }
 212  
     }
 213  
 
 214  
     /**
 215  
      * Returns the comment for the specified property key. The comment is
 216  
      * returned as it was set (either manually by calling
 217  
      * <code>setComment()</code> or when it was loaded from a properties
 218  
      * file). No modifications are performed.
 219  
      *
 220  
      * @param key the key of the property
 221  
      * @return the comment for this key (can be <b>null</b>)
 222  
      */
 223  
     public String getComment(String key)
 224  
     {
 225  293
         return fetchLayoutData(key).getComment();
 226  
     }
 227  
 
 228  
     /**
 229  
      * Sets the comment for the specified property key. The comment (or its
 230  
      * single lines if it is a multi-line comment) can start with a comment
 231  
      * character. If this is the case, it will be written without changes.
 232  
      * Otherwise a default comment character is added automatically.
 233  
      *
 234  
      * @param key the key of the property
 235  
      * @param comment the comment for this key (can be <b>null</b>, then the
 236  
      * comment will be removed)
 237  
      */
 238  
     public void setComment(String key, String comment)
 239  
     {
 240  7
         fetchLayoutData(key).setComment(comment);
 241  6
     }
 242  
 
 243  
     /**
 244  
      * Returns the number of blanc lines before this property key. If this key
 245  
      * does not exist, 0 will be returned.
 246  
      *
 247  
      * @param key the property key
 248  
      * @return the number of blanc lines before the property definition for this
 249  
      * key
 250  
      */
 251  
     public int getBlancLinesBefore(String key)
 252  
     {
 253  351
         return fetchLayoutData(key).getBlancLines();
 254  
     }
 255  
 
 256  
     /**
 257  
      * Sets the number of blanc lines before the given property key. This can be
 258  
      * used for a logical grouping of properties.
 259  
      *
 260  
      * @param key the property key
 261  
      * @param number the number of blanc lines to add before this property
 262  
      * definition
 263  
      */
 264  
     public void setBlancLinesBefore(String key, int number)
 265  
     {
 266  2
         fetchLayoutData(key).setBlancLines(number);
 267  2
     }
 268  
 
 269  
     /**
 270  
      * Returns the header comment of the represented properties file in a
 271  
      * canonical form. With the <code>commentChar</code> parameter it can be
 272  
      * specified whether comment characters should be stripped or be always
 273  
      * present.
 274  
      *
 275  
      * @param commentChar determines the presence of comment characters
 276  
      * @return the header comment (can be <b>null</b>)
 277  
      */
 278  
     public String getCanonicalHeaderComment(boolean commentChar)
 279  
     {
 280  11
         return (getHeaderComment() == null) ? null : trimComment(
 281  
                 getHeaderComment(), commentChar);
 282  
     }
 283  
 
 284  
     /**
 285  
      * Returns the header comment of the represented properties file. This
 286  
      * method returns the header comment exactly as it was set using
 287  
      * <code>setHeaderComment()</code> or extracted from the loaded properties
 288  
      * file.
 289  
      *
 290  
      * @return the header comment (can be <b>null</b>)
 291  
      */
 292  
     public String getHeaderComment()
 293  
     {
 294  10769
         return headerComment;
 295  
     }
 296  
 
 297  
     /**
 298  
      * Sets the header comment for the represented properties file. This comment
 299  
      * will be output on top of the file.
 300  
      *
 301  
      * @param comment the comment
 302  
      */
 303  
     public void setHeaderComment(String comment)
 304  
     {
 305  333
         headerComment = comment;
 306  333
     }
 307  
 
 308  
     /**
 309  
      * Returns a flag whether the specified property is defined on a single
 310  
      * line. This is meaningful only if this property has multiple values.
 311  
      *
 312  
      * @param key the property key
 313  
      * @return a flag if this property is defined on a single line
 314  
      */
 315  
     public boolean isSingleLine(String key)
 316  
     {
 317  253
         return fetchLayoutData(key).isSingleLine();
 318  
     }
 319  
 
 320  
     /**
 321  
      * Sets the &quot;single line flag&quot; for the specified property key.
 322  
      * This flag is evaluated if the property has multiple values (i.e. if it is
 323  
      * a list property). In this case, if the flag is set, all values will be
 324  
      * written in a single property definition using the list delimiter as
 325  
      * separator. Otherwise multiple lines will be written for this property,
 326  
      * each line containing one property value.
 327  
      *
 328  
      * @param key the property key
 329  
      * @param f the single line flag
 330  
      */
 331  
     public void setSingleLine(String key, boolean f)
 332  
     {
 333  1
         fetchLayoutData(key).setSingleLine(f);
 334  1
     }
 335  
 
 336  
     /**
 337  
      * Returns the &quot;force single line&quot; flag.
 338  
      *
 339  
      * @return the force single line flag
 340  
      * @see #setForceSingleLine(boolean)
 341  
      */
 342  
     public boolean isForceSingleLine()
 343  
     {
 344  249
         return forceSingleLine;
 345  
     }
 346  
 
 347  
     /**
 348  
      * Sets the &quot;force single line&quot; flag. If this flag is set, all
 349  
      * properties with multiple values are written on single lines. This mode
 350  
      * provides more compatibility with <code>java.lang.Properties</code>,
 351  
      * which cannot deal with multiple definitions of a single property.
 352  
      *
 353  
      * @param f the force single line flag
 354  
      */
 355  
     public void setForceSingleLine(boolean f)
 356  
     {
 357  1
         forceSingleLine = f;
 358  1
     }
 359  
 
 360  
     /**
 361  
      * Returns a set with all property keys managed by this object.
 362  
      *
 363  
      * @return a set with all contained property keys
 364  
      */
 365  
     public Set getKeys()
 366  
     {
 367  23
         return layoutData.keySet();
 368  
     }
 369  
 
 370  
     /**
 371  
      * Reads a properties file and stores its internal structure. The found
 372  
      * properties will be added to the associated configuration object.
 373  
      *
 374  
      * @param in the reader to the properties file
 375  
      * @throws ConfigurationException if an error occurs
 376  
      */
 377  
     public void load(Reader in) throws ConfigurationException
 378  
     {
 379  833
         if (++loadCounter == 1)
 380  
         {
 381  320
             getConfiguration().removeConfigurationListener(this);
 382  
         }
 383  833
         PropertiesConfiguration.PropertiesReader reader = new PropertiesConfiguration.PropertiesReader(
 384  
                 in, getConfiguration().getListDelimiter());
 385  
 
 386  
         try
 387  
         {
 388  21393
             while (reader.nextProperty())
 389  
             {
 390  19728
                 if (getConfiguration().propertyLoaded(reader.getPropertyName(),
 391  
                         reader.getPropertyValue()))
 392  
                 {
 393  19376
                     boolean contained = layoutData.containsKey(reader
 394  
                             .getPropertyName());
 395  19376
                     int blancLines = 0;
 396  19376
                     int idx = checkHeaderComment(reader.getCommentLines());
 397  19376
                     while (idx < reader.getCommentLines().size()
 398  
                             && ((String) reader.getCommentLines().get(idx))
 399  26608
                                     .length() < 1)
 400  
                     {
 401  7232
                         idx++;
 402  7232
                         blancLines++;
 403  
                     }
 404  19376
                     String comment = extractComment(reader.getCommentLines(),
 405  
                             idx, reader.getCommentLines().size() - 1);
 406  19376
                     PropertyLayoutData data = fetchLayoutData(reader
 407  
                             .getPropertyName());
 408  19376
                     if (contained)
 409  
                     {
 410  10881
                         data.addComment(comment);
 411  10881
                         data.setSingleLine(false);
 412  
                     }
 413  
                     else
 414  
                     {
 415  8495
                         data.setComment(comment);
 416  8495
                         data.setBlancLines(blancLines);
 417  
                     }
 418  
                 }
 419  
             }
 420  832
         }
 421  
         catch (IOException ioex)
 422  
         {
 423  0
             throw new ConfigurationException(ioex);
 424  
         }
 425  
         finally
 426  
         {
 427  1
             if (--loadCounter == 0)
 428  
             {
 429  320
                 getConfiguration().addConfigurationListener(this);
 430  
             }
 431  
         }
 432  832
     }
 433  
 
 434  
     /**
 435  
      * Writes the properties file to the given writer, preserving as much of its
 436  
      * structure as possible.
 437  
      *
 438  
      * @param out the writer
 439  
      * @throws ConfigurationException if an error occurs
 440  
      */
 441  
     public void save(Writer out) throws ConfigurationException
 442  
     {
 443  
         try
 444  
         {
 445  30
             PropertiesConfiguration.PropertiesWriter writer = new PropertiesConfiguration.PropertiesWriter(
 446  
                     out, getConfiguration().getListDelimiter());
 447  30
             if (headerComment != null)
 448  
             {
 449  5
                 writer.writeln(getCanonicalHeaderComment(true));
 450  5
                 writer.writeln(null);
 451  
             }
 452  
 
 453  310
             for (Iterator it = layoutData.keySet().iterator(); it.hasNext();)
 454  
             {
 455  250
                 String key = (String) it.next();
 456  250
                 if (getConfiguration().containsKey(key))
 457  
                 {
 458  
 
 459  
                     // Output blanc lines before property
 460  343
                     for (int i = 0; i < getBlancLinesBefore(key); i++)
 461  
                     {
 462  95
                         writer.writeln(null);
 463  
                     }
 464  
 
 465  
                     // Output the comment
 466  248
                     if (getComment(key) != null)
 467  
                     {
 468  32
                         writer.writeln(getCanonicalComment(key, true));
 469  
                     }
 470  
 
 471  
                     // Output the property and its value
 472  248
                     writer.writeProperty(key, getConfiguration().getProperty(
 473  
                             key), isForceSingleLine() || isSingleLine(key));
 474  
                 }
 475  
             }
 476  30
             writer.flush();
 477  30
         }
 478  
         catch (IOException ioex)
 479  
         {
 480  0
             throw new ConfigurationException(ioex);
 481  
         }
 482  30
     }
 483  
 
 484  
     /**
 485  
      * The event listener callback. Here event notifications of the
 486  
      * configuration object are processed to update the layout object properly.
 487  
      *
 488  
      * @param event the event object
 489  
      */
 490  
     public void configurationChanged(ConfigurationEvent event)
 491  
     {
 492  249
         if (event.isBeforeUpdate())
 493  
         {
 494  121
             if (AbstractFileConfiguration.EVENT_RELOAD == event.getType())
 495  
             {
 496  6
                 clear();
 497  
             }
 498  
         }
 499  
 
 500  
         else
 501  
         {
 502  128
             switch (event.getType())
 503  
             {
 504  
             case AbstractConfiguration.EVENT_ADD_PROPERTY:
 505  78
                 boolean contained = layoutData.containsKey(event
 506  
                         .getPropertyName());
 507  78
                 PropertyLayoutData data = fetchLayoutData(event
 508  
                         .getPropertyName());
 509  78
                 data.setSingleLine(!contained);
 510  78
                 break;
 511  
             case AbstractConfiguration.EVENT_CLEAR_PROPERTY:
 512  22
                 layoutData.remove(event.getPropertyName());
 513  22
                 break;
 514  
             case AbstractConfiguration.EVENT_CLEAR:
 515  4
                 clear();
 516  4
                 break;
 517  
             case AbstractConfiguration.EVENT_SET_PROPERTY:
 518  18
                 fetchLayoutData(event.getPropertyName());
 519  
                 break;
 520  
             }
 521  
         }
 522  249
     }
 523  
 
 524  
     /**
 525  
      * Returns a layout data object for the specified key. If this is a new key,
 526  
      * a new object is created and initialized with default values.
 527  
      *
 528  
      * @param key the key
 529  
      * @return the corresponding layout data object
 530  
      */
 531  
     private PropertyLayoutData fetchLayoutData(String key)
 532  
     {
 533  20379
         if (key == null)
 534  
         {
 535  1
             throw new IllegalArgumentException("Property key must not be null!");
 536  
         }
 537  
 
 538  20378
         PropertyLayoutData data = (PropertyLayoutData) layoutData.get(key);
 539  20378
         if (data == null)
 540  
         {
 541  8581
             data = new PropertyLayoutData();
 542  8581
             data.setSingleLine(true);
 543  8581
             layoutData.put(key, data);
 544  
         }
 545  
 
 546  20378
         return data;
 547  
     }
 548  
 
 549  
     /**
 550  
      * Removes all content from this layout object.
 551  
      */
 552  
     private void clear()
 553  
     {
 554  10
         layoutData.clear();
 555  10
         setHeaderComment(null);
 556  10
     }
 557  
 
 558  
     /**
 559  
      * Tests whether a line is a comment, i.e. whether it starts with a comment
 560  
      * character.
 561  
      *
 562  
      * @param line the line
 563  
      * @return a flag if this is a comment line
 564  
      */
 565  
     static boolean isCommentLine(String line)
 566  
     {
 567  144
         return PropertiesConfiguration.isCommentLine(line);
 568  
     }
 569  
 
 570  
     /**
 571  
      * Trims a comment. This method either removes all comment characters from
 572  
      * the given string, leaving only the plain comment text or ensures that
 573  
      * every line starts with a valid comment character.
 574  
      *
 575  
      * @param s the string to be processed
 576  
      * @param comment if <b>true</b>, a comment character will always be
 577  
      * enforced; if <b>false</b>, it will be removed
 578  
      * @return the trimmed comment
 579  
      */
 580  
     static String trimComment(String s, boolean comment)
 581  
     {
 582  51
         StringBuffer buf = new StringBuffer(s.length());
 583  51
         int lastPos = 0;
 584  
         int pos;
 585  
 
 586  
         do
 587  
         {
 588  184
             pos = s.indexOf(CR, lastPos);
 589  184
             if (pos >= 0)
 590  
             {
 591  133
                 String line = s.substring(lastPos, pos);
 592  133
                 buf.append(stripCommentChar(line, comment)).append(CR);
 593  133
                 lastPos = pos + CR.length();
 594  
             }
 595  184
         } while (pos >= 0);
 596  
 
 597  51
         if (lastPos < s.length())
 598  
         {
 599  24
             buf.append(stripCommentChar(s.substring(lastPos), comment));
 600  
         }
 601  51
         return buf.toString();
 602  
     }
 603  
 
 604  
     /**
 605  
      * Either removes the comment character from the given comment line or
 606  
      * ensures that the line starts with a comment character.
 607  
      *
 608  
      * @param s the comment line
 609  
      * @param comment if <b>true</b>, a comment character will always be
 610  
      * enforced; if <b>false</b>, it will be removed
 611  
      * @return the line without comment character
 612  
      */
 613  
     static String stripCommentChar(String s, boolean comment)
 614  
     {
 615  157
         if (s.length() < 1 || (isCommentLine(s) == comment))
 616  
         {
 617  129
             return s;
 618  
         }
 619  
 
 620  
         else
 621  
         {
 622  28
             if (!comment)
 623  
             {
 624  20
                 int pos = 0;
 625  
                 // find first comment character
 626  20
                 while (PropertiesConfiguration.COMMENT_CHARS.indexOf(s
 627  23
                         .charAt(pos)) < 0)
 628  
                 {
 629  3
                     pos++;
 630  
                 }
 631  
 
 632  
                 // Remove leading spaces
 633  20
                 pos++;
 634  20
                 while (pos < s.length()
 635  39
                         && Character.isWhitespace(s.charAt(pos)))
 636  
                 {
 637  19
                     pos++;
 638  
                 }
 639  
 
 640  20
                 return (pos < s.length()) ? s.substring(pos)
 641  
                         : StringUtils.EMPTY;
 642  
             }
 643  
             else
 644  
             {
 645  8
                 return COMMENT_PREFIX + s;
 646  
             }
 647  
         }
 648  
     }
 649  
 
 650  
     /**
 651  
      * Extracts a comment string from the given range of the specified comment
 652  
      * lines. The single lines are added using a line feed as separator.
 653  
      *
 654  
      * @param commentLines a list with comment lines
 655  
      * @param from the start index
 656  
      * @param to the end index (inclusive)
 657  
      * @return the comment string (<b>null</b> if it is undefined)
 658  
      */
 659  
     private String extractComment(List commentLines, int from, int to)
 660  
     {
 661  19685
         if (to < from)
 662  
         {
 663  17785
             return null;
 664  
         }
 665  
 
 666  
         else
 667  
         {
 668  1900
             StringBuffer buf = new StringBuffer((String) commentLines.get(from));
 669  9883
             for (int i = from + 1; i <= to; i++)
 670  
             {
 671  7983
                 buf.append(CR);
 672  7983
                 buf.append(commentLines.get(i));
 673  
             }
 674  1900
             return buf.toString();
 675  
         }
 676  
     }
 677  
 
 678  
     /**
 679  
      * Checks if parts of the passed in comment can be used as header comment.
 680  
      * This method checks whether a header comment can be defined (i.e. whether
 681  
      * this is the first comment in the loaded file). If this is the case, it is
 682  
      * searched for the lates blanc line. This line will mark the end of the
 683  
      * header comment. The return value is the index of the first line in the
 684  
      * passed in list, which does not belong to the header comment.
 685  
      *
 686  
      * @param commentLines the comment lines
 687  
      * @return the index of the next line after the header comment
 688  
      */
 689  
     private int checkHeaderComment(List commentLines)
 690  
     {
 691  19376
         if (loadCounter == 1 && getHeaderComment() == null
 692  
                 && layoutData.isEmpty())
 693  
         {
 694  
             // This is the first comment. Search for blanc lines.
 695  309
             int index = commentLines.size() - 1;
 696  309
             while (index >= 0
 697  317
                     && ((String) commentLines.get(index)).length() > 0)
 698  
             {
 699  8
                 index--;
 700  
             }
 701  309
             setHeaderComment(extractComment(commentLines, 0, index - 1));
 702  309
             return index + 1;
 703  
         }
 704  
         else
 705  
         {
 706  19067
             return 0;
 707  
         }
 708  
     }
 709  
 
 710  
     /**
 711  
      * Copies the data from the given layout object.
 712  
      *
 713  
      * @param c the layout object to copy
 714  
      */
 715  
     private void copyFrom(PropertiesConfigurationLayout c)
 716  
     {
 717  59
         for (Iterator it = c.getKeys().iterator(); it.hasNext();)
 718  
         {
 719  47
             String key = (String) it.next();
 720  47
             PropertyLayoutData data = (PropertyLayoutData) c.layoutData
 721  
                     .get(key);
 722  47
             layoutData.put(key, data.clone());
 723  
         }
 724  6
     }
 725  
 
 726  
     /**
 727  
      * A helper class for storing all layout related information for a
 728  
      * configuration property.
 729  
      */
 730  
     static class PropertyLayoutData implements Cloneable
 731  
     {
 732  
         /** Stores the comment for the property. */
 733  
         private StringBuffer comment;
 734  
 
 735  
         /** Stores the number of blanc lines before this property. */
 736  
         private int blancLines;
 737  
 
 738  
         /** Stores the single line property. */
 739  
         private boolean singleLine;
 740  
 
 741  
         /**
 742  
          * Creates a new instance of <code>PropertyLayoutData</code>.
 743  
          */
 744  
         public PropertyLayoutData()
 745  8581
         {
 746  8581
             singleLine = true;
 747  8581
         }
 748  
 
 749  
         /**
 750  
          * Returns the number of blanc lines before this property.
 751  
          *
 752  
          * @return the number of blanc lines before this property
 753  
          */
 754  
         public int getBlancLines()
 755  
         {
 756  351
             return blancLines;
 757  
         }
 758  
 
 759  
         /**
 760  
          * Sets the number of properties before this property.
 761  
          *
 762  
          * @param blancLines the number of properties before this property
 763  
          */
 764  
         public void setBlancLines(int blancLines)
 765  
         {
 766  8497
             this.blancLines = blancLines;
 767  8497
         }
 768  
 
 769  
         /**
 770  
          * Returns the single line flag.
 771  
          *
 772  
          * @return the single line flag
 773  
          */
 774  
         public boolean isSingleLine()
 775  
         {
 776  253
             return singleLine;
 777  
         }
 778  
 
 779  
         /**
 780  
          * Sets the single line flag.
 781  
          *
 782  
          * @param singleLine the single line flag
 783  
          */
 784  
         public void setSingleLine(boolean singleLine)
 785  
         {
 786  19541
             this.singleLine = singleLine;
 787  19541
         }
 788  
 
 789  
         /**
 790  
          * Adds a comment for this property. If already a comment exists, the
 791  
          * new comment is added (separated by a newline).
 792  
          *
 793  
          * @param s the comment to add
 794  
          */
 795  
         public void addComment(String s)
 796  
         {
 797  10881
             if (s != null)
 798  
             {
 799  829
                 if (comment == null)
 800  
                 {
 801  16
                     comment = new StringBuffer(s);
 802  
                 }
 803  
                 else
 804  
                 {
 805  813
                     comment.append(CR).append(s);
 806  
                 }
 807  
             }
 808  10881
         }
 809  
 
 810  
         /**
 811  
          * Sets the comment for this property.
 812  
          *
 813  
          * @param s the new comment (can be <b>null</b>)
 814  
          */
 815  
         public void setComment(String s)
 816  
         {
 817  8501
             if (s == null)
 818  
             {
 819  7450
                 comment = null;
 820  
             }
 821  
             else
 822  
             {
 823  1051
                 comment = new StringBuffer(s);
 824  
             }
 825  8501
         }
 826  
 
 827  
         /**
 828  
          * Returns the comment for this property. The comment is returned as it
 829  
          * is, without processing of comment characters.
 830  
          *
 831  
          * @return the comment (can be <b>null</b>)
 832  
          */
 833  
         public String getComment()
 834  
         {
 835  300
             return (comment == null) ? null : comment.toString();
 836  
         }
 837  
 
 838  
         /**
 839  
          * Creates a copy of this object.
 840  
          *
 841  
          * @return the copy
 842  
          */
 843  
         public Object clone()
 844  
         {
 845  
             try
 846  
             {
 847  47
                 PropertyLayoutData copy = (PropertyLayoutData) super.clone();
 848  47
                 if (comment != null)
 849  
                 {
 850  
                     // must copy string buffer, too
 851  7
                     copy.comment = new StringBuffer(getComment());
 852  
                 }
 853  47
                 return copy;
 854  
             }
 855  
             catch (CloneNotSupportedException cnex)
 856  
             {
 857  
                 // This cannot happen!
 858  0
                 throw new ConfigurationRuntimeException(cnex);
 859  
             }
 860  
         }
 861  
     }
 862  
 }