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 *      https://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.lang3.text;
018
019import java.util.regex.Matcher;
020import java.util.regex.Pattern;
021
022import org.apache.commons.lang3.ArrayUtils;
023import org.apache.commons.lang3.StringUtils;
024
025/**
026 * Operations on Strings that contain words.
027 *
028 * <p>This class tries to handle {@code null} input gracefully.
029 * An exception will not be thrown for a {@code null} input.
030 * Each method documents its behavior in more detail.</p>
031 *
032 * @since 2.0
033 * @deprecated As of <a href="https://commons.apache.org/proper/commons-lang/changes-report.html#a3.6">3.6</a>, use Apache Commons Text
034 * <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/WordUtils.html">
035 * WordUtils</a>.
036 */
037@Deprecated
038public class WordUtils {
039
040    /**
041     * Capitalizes all the whitespace separated words in a String.
042     * Only the first character of each word is changed. To convert the
043     * rest of each word to lowercase at the same time,
044     * use {@link #capitalizeFully(String)}.
045     *
046     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
047     * A {@code null} input String returns {@code null}.
048     * Capitalization uses the Unicode title case, normally equivalent to
049     * upper case.</p>
050     *
051     * <pre>
052     * WordUtils.capitalize(null)        = null
053     * WordUtils.capitalize("")          = ""
054     * WordUtils.capitalize("i am FINE") = "I Am FINE"
055     * </pre>
056     *
057     * @param str  the String to capitalize, may be null
058     * @return capitalized String, {@code null} if null String input
059     * @see #uncapitalize(String)
060     * @see #capitalizeFully(String)
061     */
062    public static String capitalize(final String str) {
063        return capitalize(str, null);
064    }
065
066    /**
067     * Capitalizes all the delimiter separated words in a String.
068     * Only the first character of each word is changed. To convert the
069     * rest of each word to lowercase at the same time,
070     * use {@link #capitalizeFully(String, char[])}.
071     *
072     * <p>The delimiters represent a set of characters understood to separate words.
073     * The first string character and the first non-delimiter character after a
074     * delimiter will be capitalized.</p>
075     *
076     * <p>A {@code null} input String returns {@code null}.
077     * Capitalization uses the Unicode title case, normally equivalent to
078     * upper case.</p>
079     *
080     * <pre>
081     * WordUtils.capitalize(null, *)            = null
082     * WordUtils.capitalize("", *)              = ""
083     * WordUtils.capitalize(*, new char[0])     = *
084     * WordUtils.capitalize("i am fine", null)  = "I Am Fine"
085     * WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"
086     * </pre>
087     *
088     * @param str  the String to capitalize, may be null
089     * @param delimiters  set of characters to determine capitalization, null means whitespace
090     * @return capitalized String, {@code null} if null String input
091     * @see #uncapitalize(String)
092     * @see #capitalizeFully(String)
093     * @since 2.1
094     */
095    public static String capitalize(final String str, final char... delimiters) {
096        final int delimLen = delimiters == null ? -1 : delimiters.length;
097        if (StringUtils.isEmpty(str) || delimLen == 0) {
098            return str;
099        }
100        final char[] buffer = str.toCharArray();
101        boolean capitalizeNext = true;
102        for (int i = 0; i < buffer.length; i++) {
103            final char ch = buffer[i];
104            if (isDelimiter(ch, delimiters)) {
105                capitalizeNext = true;
106            } else if (capitalizeNext) {
107                buffer[i] = Character.toTitleCase(ch);
108                capitalizeNext = false;
109            }
110        }
111        return new String(buffer);
112    }
113
114    /**
115     * Converts all the whitespace separated words in a String into capitalized words,
116     * that is each word is made up of a titlecase character and then a series of
117     * lowercase characters.
118     *
119     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
120     * A {@code null} input String returns {@code null}.
121     * Capitalization uses the Unicode title case, normally equivalent to
122     * upper case.</p>
123     *
124     * <pre>
125     * WordUtils.capitalizeFully(null)        = null
126     * WordUtils.capitalizeFully("")          = ""
127     * WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
128     * </pre>
129     *
130     * @param str  the String to capitalize, may be null
131     * @return capitalized String, {@code null} if null String input
132     */
133    public static String capitalizeFully(final String str) {
134        return capitalizeFully(str, null);
135    }
136
137    /**
138     * Converts all the delimiter separated words in a String into capitalized words,
139     * that is each word is made up of a titlecase character and then a series of
140     * lowercase characters.
141     *
142     * <p>The delimiters represent a set of characters understood to separate words.
143     * The first string character and the first non-delimiter character after a
144     * delimiter will be capitalized.</p>
145     *
146     * <p>A {@code null} input String returns {@code null}.
147     * Capitalization uses the Unicode title case, normally equivalent to
148     * upper case.</p>
149     *
150     * <pre>
151     * WordUtils.capitalizeFully(null, *)            = null
152     * WordUtils.capitalizeFully("", *)              = ""
153     * WordUtils.capitalizeFully(*, null)            = *
154     * WordUtils.capitalizeFully(*, new char[0])     = *
155     * WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"
156     * </pre>
157     *
158     * @param str  the String to capitalize, may be null
159     * @param delimiters  set of characters to determine capitalization, null means whitespace
160     * @return capitalized String, {@code null} if null String input
161     * @since 2.1
162     */
163    public static String capitalizeFully(final String str, final char... delimiters) {
164        final int delimLen = delimiters == null ? -1 : delimiters.length;
165        if (StringUtils.isEmpty(str) || delimLen == 0) {
166            return str;
167        }
168        return capitalize(str.toLowerCase(), delimiters);
169    }
170
171    /**
172     * Checks if the String contains all words in the given array.
173     *
174     * <p>
175     * A {@code null} String will return {@code false}. A {@code null}, zero
176     * length search array or if one element of array is null will return {@code false}.
177     * </p>
178     *
179     * <pre>
180     * WordUtils.containsAllWords(null, *)            = false
181     * WordUtils.containsAllWords("", *)              = false
182     * WordUtils.containsAllWords(*, null)            = false
183     * WordUtils.containsAllWords(*, [])              = false
184     * WordUtils.containsAllWords("abcd", "ab", "cd") = false
185     * WordUtils.containsAllWords("abc def", "def", "abc") = true
186     * </pre>
187     *
188     * @param word The CharSequence to check, may be null
189     * @param words The array of String words to search for, may be null
190     * @return {@code true} if all search words are found, {@code false} otherwise
191     * @since 3.5
192     */
193    public static boolean containsAllWords(final CharSequence word, final CharSequence... words) {
194        if (StringUtils.isEmpty(word) || ArrayUtils.isEmpty(words)) {
195            return false;
196        }
197        for (final CharSequence w : words) {
198            if (StringUtils.isBlank(w)) {
199                return false;
200            }
201            final Pattern p = Pattern.compile(".*\\b" + w + "\\b.*");
202            if (!p.matcher(word).matches()) {
203                return false;
204            }
205        }
206        return true;
207    }
208
209    /**
210     * Extracts the initial characters from each word in the String.
211     *
212     * <p>All first characters after whitespace are returned as a new string.
213     * Their case is not changed.</p>
214     *
215     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
216     * A {@code null} input String returns {@code null}.</p>
217     *
218     * <pre>
219     * WordUtils.initials(null)             = null
220     * WordUtils.initials("")               = ""
221     * WordUtils.initials("Ben John Lee")   = "BJL"
222     * WordUtils.initials("Ben J.Lee")      = "BJ"
223     * </pre>
224     *
225     * @param str  the String to get initials from, may be null
226     * @return String of initial letters, {@code null} if null String input
227     * @see #initials(String,char[])
228     * @since 2.2
229     */
230    public static String initials(final String str) {
231        return initials(str, null);
232    }
233
234    /**
235     * Extracts the initial characters from each word in the String.
236     *
237     * <p>All first characters after the defined delimiters are returned as a new string.
238     * Their case is not changed.</p>
239     *
240     * <p>If the delimiters array is null, then Whitespace is used.
241     * Whitespace is defined by {@link Character#isWhitespace(char)}.
242     * A {@code null} input String returns {@code null}.
243     * An empty delimiter array returns an empty String.</p>
244     *
245     * <pre>
246     * WordUtils.initials(null, *)                = null
247     * WordUtils.initials("", *)                  = ""
248     * WordUtils.initials("Ben John Lee", null)   = "BJL"
249     * WordUtils.initials("Ben J.Lee", null)      = "BJ"
250     * WordUtils.initials("Ben J.Lee", [' ','.']) = "BJL"
251     * WordUtils.initials(*, new char[0])         = ""
252     * </pre>
253     *
254     * @param str  the String to get initials from, may be null
255     * @param delimiters  set of characters to determine words, null means whitespace
256     * @return String of initial characters, {@code null} if null String input
257     * @see #initials(String)
258     * @since 2.2
259     */
260    public static String initials(final String str, final char... delimiters) {
261        if (StringUtils.isEmpty(str)) {
262            return str;
263        }
264        if (delimiters != null && delimiters.length == 0) {
265            return StringUtils.EMPTY;
266        }
267        final int strLen = str.length();
268        final char[] buf = new char[strLen / 2 + 1];
269        int count = 0;
270        boolean lastWasGap = true;
271        for (int i = 0; i < strLen; i++) {
272            final char ch = str.charAt(i);
273            if (isDelimiter(ch, delimiters)) {
274                lastWasGap = true;
275                continue;  // ignore ch
276            }
277            if (lastWasGap) {
278                buf[count++] = ch;
279                lastWasGap = false;
280            }
281        }
282        return new String(buf, 0, count);
283    }
284
285    /**
286     * Tests if the character is a delimiter.
287     *
288     * @param ch  the character to check
289     * @param delimiters  the delimiters
290     * @return true if it is a delimiter
291     */
292    private static boolean isDelimiter(final char ch, final char[] delimiters) {
293        return delimiters == null ? Character.isWhitespace(ch) : ArrayUtils.contains(delimiters, ch);
294    }
295
296    /**
297     * Swaps the case of a String using a word based algorithm.
298     *
299     * <ul>
300     *  <li>Upper case character converts to Lower case</li>
301     *  <li>Title case character converts to Lower case</li>
302     *  <li>Lower case character after Whitespace or at start converts to Title case</li>
303     *  <li>Other Lower case character converts to Upper case</li>
304     * </ul>
305     *
306     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
307     * A {@code null} input String returns {@code null}.</p>
308     *
309     * <pre>
310     * StringUtils.swapCase(null)                 = null
311     * StringUtils.swapCase("")                   = ""
312     * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
313     * </pre>
314     *
315     * @param str  the String to swap case, may be null
316     * @return the changed String, {@code null} if null String input
317     */
318    public static String swapCase(final String str) {
319        if (StringUtils.isEmpty(str)) {
320            return str;
321        }
322        final char[] buffer = str.toCharArray();
323
324        boolean whitespace = true;
325
326        for (int i = 0; i < buffer.length; i++) {
327            final char ch = buffer[i];
328            if (Character.isUpperCase(ch) || Character.isTitleCase(ch)) {
329                buffer[i] = Character.toLowerCase(ch);
330                whitespace = false;
331            } else if (Character.isLowerCase(ch)) {
332                if (whitespace) {
333                    buffer[i] = Character.toTitleCase(ch);
334                    whitespace = false;
335                } else {
336                    buffer[i] = Character.toUpperCase(ch);
337                }
338            } else {
339                whitespace = Character.isWhitespace(ch);
340            }
341        }
342        return new String(buffer);
343    }
344
345    /**
346     * Uncapitalizes all the whitespace separated words in a String.
347     * Only the first character of each word is changed.
348     *
349     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
350     * A {@code null} input String returns {@code null}.</p>
351     *
352     * <pre>
353     * WordUtils.uncapitalize(null)        = null
354     * WordUtils.uncapitalize("")          = ""
355     * WordUtils.uncapitalize("I Am FINE") = "i am fINE"
356     * </pre>
357     *
358     * @param str  the String to uncapitalize, may be null
359     * @return uncapitalized String, {@code null} if null String input
360     * @see #capitalize(String)
361     */
362    public static String uncapitalize(final String str) {
363        return uncapitalize(str, null);
364    }
365
366    /**
367     * Uncapitalizes all the whitespace separated words in a String.
368     * Only the first character of each word is changed.
369     *
370     * <p>The delimiters represent a set of characters understood to separate words.
371     * The first string character and the first non-delimiter character after a
372     * delimiter will be uncapitalized.</p>
373     *
374     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
375     * A {@code null} input String returns {@code null}.</p>
376     *
377     * <pre>
378     * WordUtils.uncapitalize(null, *)            = null
379     * WordUtils.uncapitalize("", *)              = ""
380     * WordUtils.uncapitalize(*, null)            = *
381     * WordUtils.uncapitalize(*, new char[0])     = *
382     * WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"
383     * </pre>
384     *
385     * @param str  the String to uncapitalize, may be null
386     * @param delimiters  set of characters to determine uncapitalization, null means whitespace
387     * @return uncapitalized String, {@code null} if null String input
388     * @see #capitalize(String)
389     * @since 2.1
390     */
391    public static String uncapitalize(final String str, final char... delimiters) {
392        final int delimLen = delimiters == null ? -1 : delimiters.length;
393        if (StringUtils.isEmpty(str) || delimLen == 0) {
394            return str;
395        }
396        final char[] buffer = str.toCharArray();
397        boolean uncapitalizeNext = true;
398        for (int i = 0; i < buffer.length; i++) {
399            final char ch = buffer[i];
400            if (isDelimiter(ch, delimiters)) {
401                uncapitalizeNext = true;
402            } else if (uncapitalizeNext) {
403                buffer[i] = Character.toLowerCase(ch);
404                uncapitalizeNext = false;
405            }
406        }
407        return new String(buffer);
408    }
409
410    /**
411     * Wraps a single line of text, identifying words by {@code ' '}.
412     *
413     * <p>New lines will be separated by the system property line separator.
414     * Very long words, such as URLs will <em>not</em> be wrapped.</p>
415     *
416     * <p>Leading spaces on a new line are stripped.
417     * Trailing spaces are not stripped.</p>
418     *
419     * <table border="1">
420     *  <caption>Examples</caption>
421     *  <tr>
422     *   <th>input</th>
423     *   <th>wrapLength</th>
424     *   <th>result</th>
425     *  </tr>
426     *  <tr>
427     *   <td>null</td>
428     *   <td>*</td>
429     *   <td>null</td>
430     *  </tr>
431     *  <tr>
432     *   <td>""</td>
433     *   <td>*</td>
434     *   <td>""</td>
435     *  </tr>
436     *  <tr>
437     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
438     *   <td>20</td>
439     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
440     *  </tr>
441     *  <tr>
442     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
443     *   <td>20</td>
444     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
445     *  </tr>
446     *  <tr>
447     *   <td>"Click here, https://commons.apache.org, to jump to the commons website"</td>
448     *   <td>20</td>
449     *   <td>"Click here,\nhttps://commons.apache.org,\nto jump to the\ncommons website"</td>
450     *  </tr>
451     * </table>
452     *
453     * (assuming that '\n' is the systems line separator)
454     *
455     * @param str  the String to be word wrapped, may be null
456     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
457     * @return a line with newlines inserted, {@code null} if null input
458     */
459    public static String wrap(final String str, final int wrapLength) {
460        return wrap(str, wrapLength, null, false);
461    }
462
463    /**
464     * Wraps a single line of text, identifying words by {@code ' '}.
465     *
466     * <p>Leading spaces on a new line are stripped.
467     * Trailing spaces are not stripped.</p>
468     *
469     * <table border="1">
470     *  <caption>Examples</caption>
471     *  <tr>
472     *   <th>input</th>
473     *   <th>wrapLength</th>
474     *   <th>newLineString</th>
475     *   <th>wrapLongWords</th>
476     *   <th>result</th>
477     *  </tr>
478     *  <tr>
479     *   <td>null</td>
480     *   <td>*</td>
481     *   <td>*</td>
482     *   <td>true/false</td>
483     *   <td>null</td>
484     *  </tr>
485     *  <tr>
486     *   <td>""</td>
487     *   <td>*</td>
488     *   <td>*</td>
489     *   <td>true/false</td>
490     *   <td>""</td>
491     *  </tr>
492     *  <tr>
493     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
494     *   <td>20</td>
495     *   <td>"\n"</td>
496     *   <td>true/false</td>
497     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
498     *  </tr>
499     *  <tr>
500     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
501     *   <td>20</td>
502     *   <td>"&lt;br /&gt;"</td>
503     *   <td>true/false</td>
504     *   <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>
505     *  </tr>
506     *  <tr>
507     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
508     *   <td>20</td>
509     *   <td>null</td>
510     *   <td>true/false</td>
511     *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
512     *  </tr>
513     *  <tr>
514     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
515     *   <td>20</td>
516     *   <td>"\n"</td>
517     *   <td>false</td>
518     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
519     *  </tr>
520     *  <tr>
521     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
522     *   <td>20</td>
523     *   <td>"\n"</td>
524     *   <td>true</td>
525     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apach\ne.org"</td>
526     *  </tr>
527     * </table>
528     *
529     * @param str  the String to be word wrapped, may be null
530     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
531     * @param newLineStr  the string to insert for a new line,
532     *  {@code null} uses the system property line separator
533     * @param wrapLongWords  true if long words (such as URLs) should be wrapped
534     * @return a line with newlines inserted, {@code null} if null input
535     */
536    public static String wrap(final String str, final int wrapLength, final String newLineStr, final boolean wrapLongWords) {
537        return wrap(str, wrapLength, newLineStr, wrapLongWords, " ");
538    }
539
540    /**
541     * Wraps a single line of text, identifying words by {@code wrapOn}.
542     *
543     * <p>Leading spaces on a new line are stripped.
544     * Trailing spaces are not stripped.</p>
545     *
546     * <table border="1">
547     *  <caption>Examples</caption>
548     *  <tr>
549     *   <th>input</th>
550     *   <th>wrapLength</th>
551     *   <th>newLineString</th>
552     *   <th>wrapLongWords</th>
553     *   <th>wrapOn</th>
554     *   <th>result</th>
555     *  </tr>
556     *  <tr>
557     *   <td>null</td>
558     *   <td>*</td>
559     *   <td>*</td>
560     *   <td>true/false</td>
561     *   <td>*</td>
562     *   <td>null</td>
563     *  </tr>
564     *  <tr>
565     *   <td>""</td>
566     *   <td>*</td>
567     *   <td>*</td>
568     *   <td>true/false</td>
569     *   <td>*</td>
570     *   <td>""</td>
571     *  </tr>
572     *  <tr>
573     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
574     *   <td>20</td>
575     *   <td>"\n"</td>
576     *   <td>true/false</td>
577     *   <td>" "</td>
578     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
579     *  </tr>
580     *  <tr>
581     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
582     *   <td>20</td>
583     *   <td>"&lt;br /&gt;"</td>
584     *   <td>true/false</td>
585     *   <td>" "</td>
586     *   <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>
587     *  </tr>
588     *  <tr>
589     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
590     *   <td>20</td>
591     *   <td>null</td>
592     *   <td>true/false</td>
593     *   <td>" "</td>
594     *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
595     *  </tr>
596     *  <tr>
597     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
598     *   <td>20</td>
599     *   <td>"\n"</td>
600     *   <td>false</td>
601     *   <td>" "</td>
602     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
603     *  </tr>
604     *  <tr>
605     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
606     *   <td>20</td>
607     *   <td>"\n"</td>
608     *   <td>true</td>
609     *   <td>" "</td>
610     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apach\ne.org"</td>
611     *  </tr>
612     *  <tr>
613     *   <td>"flammable/inflammable"</td>
614     *   <td>20</td>
615     *   <td>"\n"</td>
616     *   <td>true</td>
617     *   <td>"/"</td>
618     *   <td>"flammable\ninflammable"</td>
619     *  </tr>
620     * </table>
621     * @param str  the String to be word wrapped, may be null
622     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
623     * @param newLineStr  the string to insert for a new line,
624     *  {@code null} uses the system property line separator
625     * @param wrapLongWords  true if long words (such as URLs) should be wrapped
626     * @param wrapOn regex expression to be used as a breakable characters,
627     *               if blank string is provided a space character will be used
628     * @return a line with newlines inserted, {@code null} if null input
629     */
630    public static String wrap(final String str, int wrapLength, String newLineStr, final boolean wrapLongWords, String wrapOn) {
631        if (str == null) {
632            return null;
633        }
634        if (newLineStr == null) {
635            newLineStr = System.lineSeparator();
636        }
637        if (wrapLength < 1) {
638            wrapLength = 1;
639        }
640        if (StringUtils.isBlank(wrapOn)) {
641            wrapOn = " ";
642        }
643        final Pattern patternToWrapOn = Pattern.compile(wrapOn);
644        final int inputLineLength = str.length();
645        int offset = 0;
646        final StringBuilder wrappedLine = new StringBuilder(inputLineLength + 32);
647
648        while (offset < inputLineLength) {
649            int spaceToWrapAt = -1;
650            Matcher matcher = patternToWrapOn.matcher(
651                str.substring(offset, Math.min((int) Math.min(Integer.MAX_VALUE, offset + wrapLength + 1L), inputLineLength)));
652            if (matcher.find()) {
653                if (matcher.start() == 0) {
654                    offset += matcher.end();
655                    continue;
656                }
657                spaceToWrapAt = matcher.start() + offset;
658            }
659
660            // only last line without leading spaces is left
661            if (inputLineLength - offset <= wrapLength) {
662                break;
663            }
664
665            while (matcher.find()) {
666                spaceToWrapAt = matcher.start() + offset;
667            }
668
669            if (spaceToWrapAt >= offset) {
670                // normal case
671                wrappedLine.append(str, offset, spaceToWrapAt);
672                wrappedLine.append(newLineStr);
673                offset = spaceToWrapAt + 1;
674
675            } else // really long word or URL
676            if (wrapLongWords) {
677                // wrap really long word one line at a time
678                wrappedLine.append(str, offset, wrapLength + offset);
679                wrappedLine.append(newLineStr);
680                offset += wrapLength;
681            } else {
682                // do not wrap really long word, just extend beyond limit
683                matcher = patternToWrapOn.matcher(str.substring(offset + wrapLength));
684                if (matcher.find()) {
685                    spaceToWrapAt = matcher.start() + offset + wrapLength;
686                }
687
688                if (spaceToWrapAt >= 0) {
689                    wrappedLine.append(str, offset, spaceToWrapAt);
690                    wrappedLine.append(newLineStr);
691                    offset = spaceToWrapAt + 1;
692                } else {
693                    wrappedLine.append(str, offset, str.length());
694                    offset = inputLineLength;
695                }
696            }
697        }
698
699        // Whatever is left in line is short enough to just pass through
700        wrappedLine.append(str, offset, str.length());
701
702        return wrappedLine.toString();
703    }
704
705    /**
706     * {@link WordUtils} instances should NOT be constructed in
707     * standard programming. Instead, the class should be used as
708     * {@code WordUtils.wrap("foo bar", 20);}.
709     *
710     * <p>This constructor is public to permit tools that require a JavaBean
711     * instance to operate.</p>
712     */
713    public WordUtils() {
714    }
715
716}