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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.lang3.text;
18  
19  import java.util.regex.Matcher;
20  import java.util.regex.Pattern;
21  
22  import org.apache.commons.lang3.ArrayUtils;
23  import org.apache.commons.lang3.StringUtils;
24  
25  /**
26   * Operations on Strings that contain words.
27   *
28   * <p>This class tries to handle {@code null} input gracefully.
29   * An exception will not be thrown for a {@code null} input.
30   * Each method documents its behavior in more detail.</p>
31   *
32   * @since 2.0
33   * @deprecated As of 3.6, use Apache Commons Text
34   * <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/WordUtils.html">
35   * WordUtils</a> instead
36   */
37  @Deprecated
38  public class WordUtils {
39  
40      // Capitalizing
41      /**
42       * Capitalizes all the whitespace separated words in a String.
43       * Only the first character of each word is changed. To convert the
44       * rest of each word to lowercase at the same time,
45       * use {@link #capitalizeFully(String)}.
46       *
47       * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
48       * A {@code null} input String returns {@code null}.
49       * Capitalization uses the Unicode title case, normally equivalent to
50       * upper case.</p>
51       *
52       * <pre>
53       * WordUtils.capitalize(null)        = null
54       * WordUtils.capitalize("")          = ""
55       * WordUtils.capitalize("i am FINE") = "I Am FINE"
56       * </pre>
57       *
58       * @param str  the String to capitalize, may be null
59       * @return capitalized String, {@code null} if null String input
60       * @see #uncapitalize(String)
61       * @see #capitalizeFully(String)
62       */
63      public static String capitalize(final String str) {
64          return capitalize(str, null);
65      }
66  
67      /**
68       * Capitalizes all the delimiter separated words in a String.
69       * Only the first character of each word is changed. To convert the
70       * rest of each word to lowercase at the same time,
71       * use {@link #capitalizeFully(String, char[])}.
72       *
73       * <p>The delimiters represent a set of characters understood to separate words.
74       * The first string character and the first non-delimiter character after a
75       * delimiter will be capitalized.</p>
76       *
77       * <p>A {@code null} input String returns {@code null}.
78       * Capitalization uses the Unicode title case, normally equivalent to
79       * upper case.</p>
80       *
81       * <pre>
82       * WordUtils.capitalize(null, *)            = null
83       * WordUtils.capitalize("", *)              = ""
84       * WordUtils.capitalize(*, new char[0])     = *
85       * WordUtils.capitalize("i am fine", null)  = "I Am Fine"
86       * WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"
87       * </pre>
88       *
89       * @param str  the String to capitalize, may be null
90       * @param delimiters  set of characters to determine capitalization, null means whitespace
91       * @return capitalized String, {@code null} if null String input
92       * @see #uncapitalize(String)
93       * @see #capitalizeFully(String)
94       * @since 2.1
95       */
96      public static String capitalize(final String str, final char... delimiters) {
97          final int delimLen = delimiters == null ? -1 : delimiters.length;
98          if (StringUtils.isEmpty(str) || delimLen == 0) {
99              return str;
100         }
101         final char[] buffer = str.toCharArray();
102         boolean capitalizeNext = true;
103         for (int i = 0; i < buffer.length; i++) {
104             final char ch = buffer[i];
105             if (isDelimiter(ch, delimiters)) {
106                 capitalizeNext = true;
107             } else if (capitalizeNext) {
108                 buffer[i] = Character.toTitleCase(ch);
109                 capitalizeNext = false;
110             }
111         }
112         return new String(buffer);
113     }
114 
115     /**
116      * Converts all the whitespace separated words in a String into capitalized words,
117      * that is each word is made up of a titlecase character and then a series of
118      * lowercase characters.
119      *
120      * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
121      * A {@code null} input String returns {@code null}.
122      * Capitalization uses the Unicode title case, normally equivalent to
123      * upper case.</p>
124      *
125      * <pre>
126      * WordUtils.capitalizeFully(null)        = null
127      * WordUtils.capitalizeFully("")          = ""
128      * WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
129      * </pre>
130      *
131      * @param str  the String to capitalize, may be null
132      * @return capitalized String, {@code null} if null String input
133      */
134     public static String capitalizeFully(final String str) {
135         return capitalizeFully(str, null);
136     }
137 
138     /**
139      * Converts all the delimiter separated words in a String into capitalized words,
140      * that is each word is made up of a titlecase character and then a series of
141      * lowercase characters.
142      *
143      * <p>The delimiters represent a set of characters understood to separate words.
144      * The first string character and the first non-delimiter character after a
145      * delimiter will be capitalized.</p>
146      *
147      * <p>A {@code null} input String returns {@code null}.
148      * Capitalization uses the Unicode title case, normally equivalent to
149      * upper case.</p>
150      *
151      * <pre>
152      * WordUtils.capitalizeFully(null, *)            = null
153      * WordUtils.capitalizeFully("", *)              = ""
154      * WordUtils.capitalizeFully(*, null)            = *
155      * WordUtils.capitalizeFully(*, new char[0])     = *
156      * WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"
157      * </pre>
158      *
159      * @param str  the String to capitalize, may be null
160      * @param delimiters  set of characters to determine capitalization, null means whitespace
161      * @return capitalized String, {@code null} if null String input
162      * @since 2.1
163      */
164     public static String capitalizeFully(final String str, final char... delimiters) {
165         final int delimLen = delimiters == null ? -1 : delimiters.length;
166         if (StringUtils.isEmpty(str) || delimLen == 0) {
167             return str;
168         }
169         return capitalize(str.toLowerCase(), delimiters);
170     }
171 
172     /**
173      * Checks if the String contains all words in the given array.
174      *
175      * <p>
176      * A {@code null} String will return {@code false}. A {@code null}, zero
177      * length search array or if one element of array is null will return {@code false}.
178      * </p>
179      *
180      * <pre>
181      * WordUtils.containsAllWords(null, *)            = false
182      * WordUtils.containsAllWords("", *)              = false
183      * WordUtils.containsAllWords(*, null)            = false
184      * WordUtils.containsAllWords(*, [])              = false
185      * WordUtils.containsAllWords("abcd", "ab", "cd") = false
186      * WordUtils.containsAllWords("abc def", "def", "abc") = true
187      * </pre>
188      *
189      * @param word The CharSequence to check, may be null
190      * @param words The array of String words to search for, may be null
191      * @return {@code true} if all search words are found, {@code false} otherwise
192      * @since 3.5
193      */
194     public static boolean containsAllWords(final CharSequence word, final CharSequence... words) {
195         if (StringUtils.isEmpty(word) || ArrayUtils.isEmpty(words)) {
196             return false;
197         }
198         for (final CharSequence w : words) {
199             if (StringUtils.isBlank(w)) {
200                 return false;
201             }
202             final Pattern p = Pattern.compile(".*\\b" + w + "\\b.*");
203             if (!p.matcher(word).matches()) {
204                 return false;
205             }
206         }
207         return true;
208     }
209 
210     /**
211      * Extracts the initial characters from each word in the String.
212      *
213      * <p>All first characters after whitespace are returned as a new string.
214      * Their case is not changed.</p>
215      *
216      * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
217      * A {@code null} input String returns {@code null}.</p>
218      *
219      * <pre>
220      * WordUtils.initials(null)             = null
221      * WordUtils.initials("")               = ""
222      * WordUtils.initials("Ben John Lee")   = "BJL"
223      * WordUtils.initials("Ben J.Lee")      = "BJ"
224      * </pre>
225      *
226      * @param str  the String to get initials from, may be null
227      * @return String of initial letters, {@code null} if null String input
228      * @see #initials(String,char[])
229      * @since 2.2
230      */
231     public static String initials(final String str) {
232         return initials(str, null);
233     }
234 
235     /**
236      * Extracts the initial characters from each word in the String.
237      *
238      * <p>All first characters after the defined delimiters are returned as a new string.
239      * Their case is not changed.</p>
240      *
241      * <p>If the delimiters array is null, then Whitespace is used.
242      * Whitespace is defined by {@link Character#isWhitespace(char)}.
243      * A {@code null} input String returns {@code null}.
244      * An empty delimiter array returns an empty String.</p>
245      *
246      * <pre>
247      * WordUtils.initials(null, *)                = null
248      * WordUtils.initials("", *)                  = ""
249      * WordUtils.initials("Ben John Lee", null)   = "BJL"
250      * WordUtils.initials("Ben J.Lee", null)      = "BJ"
251      * WordUtils.initials("Ben J.Lee", [' ','.']) = "BJL"
252      * WordUtils.initials(*, new char[0])         = ""
253      * </pre>
254      *
255      * @param str  the String to get initials from, may be null
256      * @param delimiters  set of characters to determine words, null means whitespace
257      * @return String of initial characters, {@code null} if null String input
258      * @see #initials(String)
259      * @since 2.2
260      */
261     public static String initials(final String str, final char... delimiters) {
262         if (StringUtils.isEmpty(str)) {
263             return str;
264         }
265         if (delimiters != null && delimiters.length == 0) {
266             return StringUtils.EMPTY;
267         }
268         final int strLen = str.length();
269         final char[] buf = new char[strLen / 2 + 1];
270         int count = 0;
271         boolean lastWasGap = true;
272         for (int i = 0; i < strLen; i++) {
273             final char ch = str.charAt(i);
274             if (isDelimiter(ch, delimiters)) {
275                 lastWasGap = true;
276             } else if (lastWasGap) {
277                 buf[count++] = ch;
278                 lastWasGap = false;
279             } else {
280                 continue; // ignore ch
281             }
282         }
283         return new String(buf, 0, count);
284     }
285 
286     /**
287      * Tests if the character is a delimiter.
288      *
289      * @param ch  the character to check
290      * @param delimiters  the delimiters
291      * @return true if it is a delimiter
292      */
293     private static boolean isDelimiter(final char ch, final char[] delimiters) {
294         return delimiters == null ? Character.isWhitespace(ch) : ArrayUtils.contains(delimiters, ch);
295     }
296 
297     /**
298      * Swaps the case of a String using a word based algorithm.
299      *
300      * <ul>
301      *  <li>Upper case character converts to Lower case</li>
302      *  <li>Title case character converts to Lower case</li>
303      *  <li>Lower case character after Whitespace or at start converts to Title case</li>
304      *  <li>Other Lower case character converts to Upper case</li>
305      * </ul>
306      *
307      * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
308      * A {@code null} input String returns {@code null}.</p>
309      *
310      * <pre>
311      * StringUtils.swapCase(null)                 = null
312      * StringUtils.swapCase("")                   = ""
313      * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
314      * </pre>
315      *
316      * @param str  the String to swap case, may be null
317      * @return the changed String, {@code null} if null String input
318      */
319     public static String swapCase(final String str) {
320         if (StringUtils.isEmpty(str)) {
321             return str;
322         }
323         final char[] buffer = str.toCharArray();
324 
325         boolean whitespace = true;
326 
327         for (int i = 0; i < buffer.length; i++) {
328             final char ch = buffer[i];
329             if (Character.isUpperCase(ch) || Character.isTitleCase(ch)) {
330                 buffer[i] = Character.toLowerCase(ch);
331                 whitespace = false;
332             } else if (Character.isLowerCase(ch)) {
333                 if (whitespace) {
334                     buffer[i] = Character.toTitleCase(ch);
335                     whitespace = false;
336                 } else {
337                     buffer[i] = Character.toUpperCase(ch);
338                 }
339             } else {
340                 whitespace = Character.isWhitespace(ch);
341             }
342         }
343         return new String(buffer);
344     }
345 
346     /**
347      * Uncapitalizes all the whitespace separated words in a String.
348      * Only the first character of each word is changed.
349      *
350      * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
351      * A {@code null} input String returns {@code null}.</p>
352      *
353      * <pre>
354      * WordUtils.uncapitalize(null)        = null
355      * WordUtils.uncapitalize("")          = ""
356      * WordUtils.uncapitalize("I Am FINE") = "i am fINE"
357      * </pre>
358      *
359      * @param str  the String to uncapitalize, may be null
360      * @return uncapitalized String, {@code null} if null String input
361      * @see #capitalize(String)
362      */
363     public static String uncapitalize(final String str) {
364         return uncapitalize(str, null);
365     }
366 
367     /**
368      * Uncapitalizes all the whitespace separated words in a String.
369      * Only the first character of each word is changed.
370      *
371      * <p>The delimiters represent a set of characters understood to separate words.
372      * The first string character and the first non-delimiter character after a
373      * delimiter will be uncapitalized.</p>
374      *
375      * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
376      * A {@code null} input String returns {@code null}.</p>
377      *
378      * <pre>
379      * WordUtils.uncapitalize(null, *)            = null
380      * WordUtils.uncapitalize("", *)              = ""
381      * WordUtils.uncapitalize(*, null)            = *
382      * WordUtils.uncapitalize(*, new char[0])     = *
383      * WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"
384      * </pre>
385      *
386      * @param str  the String to uncapitalize, may be null
387      * @param delimiters  set of characters to determine uncapitalization, null means whitespace
388      * @return uncapitalized String, {@code null} if null String input
389      * @see #capitalize(String)
390      * @since 2.1
391      */
392     public static String uncapitalize(final String str, final char... delimiters) {
393         final int delimLen = delimiters == null ? -1 : delimiters.length;
394         if (StringUtils.isEmpty(str) || delimLen == 0) {
395             return str;
396         }
397         final char[] buffer = str.toCharArray();
398         boolean uncapitalizeNext = true;
399         for (int i = 0; i < buffer.length; i++) {
400             final char ch = buffer[i];
401             if (isDelimiter(ch, delimiters)) {
402                 uncapitalizeNext = true;
403             } else if (uncapitalizeNext) {
404                 buffer[i] = Character.toLowerCase(ch);
405                 uncapitalizeNext = false;
406             }
407         }
408         return new String(buffer);
409     }
410 
411     /**
412      * Wraps a single line of text, identifying words by {@code ' '}.
413      *
414      * <p>New lines will be separated by the system property line separator.
415      * Very long words, such as URLs will <i>not</i> be wrapped.</p>
416      *
417      * <p>Leading spaces on a new line are stripped.
418      * Trailing spaces are not stripped.</p>
419      *
420      * <table border="1">
421      *  <caption>Examples</caption>
422      *  <tr>
423      *   <th>input</th>
424      *   <th>wrapLength</th>
425      *   <th>result</th>
426      *  </tr>
427      *  <tr>
428      *   <td>null</td>
429      *   <td>*</td>
430      *   <td>null</td>
431      *  </tr>
432      *  <tr>
433      *   <td>""</td>
434      *   <td>*</td>
435      *   <td>""</td>
436      *  </tr>
437      *  <tr>
438      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
439      *   <td>20</td>
440      *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
441      *  </tr>
442      *  <tr>
443      *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
444      *   <td>20</td>
445      *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
446      *  </tr>
447      *  <tr>
448      *   <td>"Click here, https://commons.apache.org, to jump to the commons website"</td>
449      *   <td>20</td>
450      *   <td>"Click here,\nhttps://commons.apache.org,\nto jump to the\ncommons website"</td>
451      *  </tr>
452      * </table>
453      *
454      * (assuming that '\n' is the systems line separator)
455      *
456      * @param str  the String to be word wrapped, may be null
457      * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
458      * @return a line with newlines inserted, {@code null} if null input
459      */
460     public static String wrap(final String str, final int wrapLength) {
461         return wrap(str, wrapLength, null, false);
462     }
463 
464     /**
465      * Wraps a single line of text, identifying words by {@code ' '}.
466      *
467      * <p>Leading spaces on a new line are stripped.
468      * Trailing spaces are not stripped.</p>
469      *
470      * <table border="1">
471      *  <caption>Examples</caption>
472      *  <tr>
473      *   <th>input</th>
474      *   <th>wrapLength</th>
475      *   <th>newLineString</th>
476      *   <th>wrapLongWords</th>
477      *   <th>result</th>
478      *  </tr>
479      *  <tr>
480      *   <td>null</td>
481      *   <td>*</td>
482      *   <td>*</td>
483      *   <td>true/false</td>
484      *   <td>null</td>
485      *  </tr>
486      *  <tr>
487      *   <td>""</td>
488      *   <td>*</td>
489      *   <td>*</td>
490      *   <td>true/false</td>
491      *   <td>""</td>
492      *  </tr>
493      *  <tr>
494      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
495      *   <td>20</td>
496      *   <td>"\n"</td>
497      *   <td>true/false</td>
498      *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
499      *  </tr>
500      *  <tr>
501      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
502      *   <td>20</td>
503      *   <td>"&lt;br /&gt;"</td>
504      *   <td>true/false</td>
505      *   <td>"Here is one line of&lt;br /&gt;text that is going&lt;br /&gt;to be wrapped after&lt;br /&gt;20 columns."</td>
506      *  </tr>
507      *  <tr>
508      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
509      *   <td>20</td>
510      *   <td>null</td>
511      *   <td>true/false</td>
512      *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
513      *  </tr>
514      *  <tr>
515      *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
516      *   <td>20</td>
517      *   <td>"\n"</td>
518      *   <td>false</td>
519      *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
520      *  </tr>
521      *  <tr>
522      *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
523      *   <td>20</td>
524      *   <td>"\n"</td>
525      *   <td>true</td>
526      *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"</td>
527      *  </tr>
528      * </table>
529      *
530      * @param str  the String to be word wrapped, may be null
531      * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
532      * @param newLineStr  the string to insert for a new line,
533      *  {@code null} uses the system property line separator
534      * @param wrapLongWords  true if long words (such as URLs) should be wrapped
535      * @return a line with newlines inserted, {@code null} if null input
536      */
537     public static String wrap(final String str, final int wrapLength, final String newLineStr, final boolean wrapLongWords) {
538         return wrap(str, wrapLength, newLineStr, wrapLongWords, " ");
539     }
540 
541     /**
542      * Wraps a single line of text, identifying words by {@code wrapOn}.
543      *
544      * <p>Leading spaces on a new line are stripped.
545      * Trailing spaces are not stripped.</p>
546      *
547      * <table border="1">
548      *  <caption>Examples</caption>
549      *  <tr>
550      *   <th>input</th>
551      *   <th>wrapLength</th>
552      *   <th>newLineString</th>
553      *   <th>wrapLongWords</th>
554      *   <th>wrapOn</th>
555      *   <th>result</th>
556      *  </tr>
557      *  <tr>
558      *   <td>null</td>
559      *   <td>*</td>
560      *   <td>*</td>
561      *   <td>true/false</td>
562      *   <td>*</td>
563      *   <td>null</td>
564      *  </tr>
565      *  <tr>
566      *   <td>""</td>
567      *   <td>*</td>
568      *   <td>*</td>
569      *   <td>true/false</td>
570      *   <td>*</td>
571      *   <td>""</td>
572      *  </tr>
573      *  <tr>
574      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
575      *   <td>20</td>
576      *   <td>"\n"</td>
577      *   <td>true/false</td>
578      *   <td>" "</td>
579      *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
580      *  </tr>
581      *  <tr>
582      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
583      *   <td>20</td>
584      *   <td>"&lt;br /&gt;"</td>
585      *   <td>true/false</td>
586      *   <td>" "</td>
587      *   <td>"Here is one line of&lt;br /&gt;text that is going&lt;br /&gt;to be wrapped after&lt;br /&gt;20 columns."</td>
588      *  </tr>
589      *  <tr>
590      *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
591      *   <td>20</td>
592      *   <td>null</td>
593      *   <td>true/false</td>
594      *   <td>" "</td>
595      *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
596      *  </tr>
597      *  <tr>
598      *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
599      *   <td>20</td>
600      *   <td>"\n"</td>
601      *   <td>false</td>
602      *   <td>" "</td>
603      *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
604      *  </tr>
605      *  <tr>
606      *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
607      *   <td>20</td>
608      *   <td>"\n"</td>
609      *   <td>true</td>
610      *   <td>" "</td>
611      *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"</td>
612      *  </tr>
613      *  <tr>
614      *   <td>"flammable/inflammable"</td>
615      *   <td>20</td>
616      *   <td>"\n"</td>
617      *   <td>true</td>
618      *   <td>"/"</td>
619      *   <td>"flammable\ninflammable"</td>
620      *  </tr>
621      * </table>
622      * @param str  the String to be word wrapped, may be null
623      * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
624      * @param newLineStr  the string to insert for a new line,
625      *  {@code null} uses the system property line separator
626      * @param wrapLongWords  true if long words (such as URLs) should be wrapped
627      * @param wrapOn regex expression to be used as a breakable characters,
628      *               if blank string is provided a space character will be used
629      * @return a line with newlines inserted, {@code null} if null input
630      */
631     public static String wrap(final String str, int wrapLength, String newLineStr, final boolean wrapLongWords, String wrapOn) {
632         if (str == null) {
633             return null;
634         }
635         if (newLineStr == null) {
636             newLineStr = System.lineSeparator();
637         }
638         if (wrapLength < 1) {
639             wrapLength = 1;
640         }
641         if (StringUtils.isBlank(wrapOn)) {
642             wrapOn = " ";
643         }
644         final Pattern patternToWrapOn = Pattern.compile(wrapOn);
645         final int inputLineLength = str.length();
646         int offset = 0;
647         final StringBuilder wrappedLine = new StringBuilder(inputLineLength + 32);
648 
649         while (offset < inputLineLength) {
650             int spaceToWrapAt = -1;
651             Matcher matcher = patternToWrapOn.matcher(
652                 str.substring(offset, Math.min((int) Math.min(Integer.MAX_VALUE, offset + wrapLength + 1L), inputLineLength)));
653             if (matcher.find()) {
654                 if (matcher.start() == 0) {
655                     offset += matcher.end();
656                     continue;
657                 }
658                 spaceToWrapAt = matcher.start() + offset;
659             }
660 
661             // only last line without leading spaces is left
662             if (inputLineLength - offset <= wrapLength) {
663                 break;
664             }
665 
666             while (matcher.find()) {
667                 spaceToWrapAt = matcher.start() + offset;
668             }
669 
670             if (spaceToWrapAt >= offset) {
671                 // normal case
672                 wrappedLine.append(str, offset, spaceToWrapAt);
673                 wrappedLine.append(newLineStr);
674                 offset = spaceToWrapAt + 1;
675 
676             } else // really long word or URL
677             if (wrapLongWords) {
678                 // wrap really long word one line at a time
679                 wrappedLine.append(str, offset, wrapLength + offset);
680                 wrappedLine.append(newLineStr);
681                 offset += wrapLength;
682             } else {
683                 // do not wrap really long word, just extend beyond limit
684                 matcher = patternToWrapOn.matcher(str.substring(offset + wrapLength));
685                 if (matcher.find()) {
686                     spaceToWrapAt = matcher.start() + offset + wrapLength;
687                 }
688 
689                 if (spaceToWrapAt >= 0) {
690                     wrappedLine.append(str, offset, spaceToWrapAt);
691                     wrappedLine.append(newLineStr);
692                     offset = spaceToWrapAt + 1;
693                 } else {
694                     wrappedLine.append(str, offset, str.length());
695                     offset = inputLineLength;
696                 }
697             }
698         }
699 
700         // Whatever is left in line is short enough to just pass through
701         wrappedLine.append(str, offset, str.length());
702 
703         return wrappedLine.toString();
704     }
705 
706     /**
707      * {@link WordUtils} instances should NOT be constructed in
708      * standard programming. Instead, the class should be used as
709      * {@code WordUtils.wrap("foo bar", 20);}.
710      *
711      * <p>This constructor is public to permit tools that require a JavaBean
712      * instance to operate.</p>
713      */
714     public WordUtils() {
715     }
716 
717 }