    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.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 * <p>Operations on Strings that contain words.</p>
    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 3.6, use commons-text
    034 * <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/WordUtils.html">
    035 * WordUtils</a> instead
    036 */
    037@Deprecated
    038public class WordUtils {
    039
    040    /**
    041     * <p>{@code WordUtils} instances should NOT be constructed in
    042     * standard programming. Instead, the class should be used as
    043     * {@code WordUtils.wrap("foo bar", 20);}.</p>
    044     *
    045     * <p>This constructor is public to permit tools that require a JavaBean
    046     * instance to operate.</p>
    047     */
    048    public WordUtils() {
    049    }
    050
    051    // Wrapping
    052    //--------------------------------------------------------------------------
    053    /**
    054     * <p>Wraps a single line of text, identifying words by {@code ' '}.</p>
    055     *
    056     * <p>New lines will be separated by the system property line separator.
    057     * Very long words, such as URLs will <i>not</i> be wrapped.</p>
    058     *
    059     * <p>Leading spaces on a new line are stripped.
    060     * Trailing spaces are not stripped.</p>
    061     *
    062     * <table border="1">
    063     *  <caption>Examples</caption>
    064     *  <tr>
    065     *   <th>input</th>
    066     *   <th>wrapLength</th>
    067     *   <th>result</th>
    068     *  </tr>
    069     *  <tr>
    070     *   <td>null</td>
    071     *   <td>*</td>
    072     *   <td>null</td>
    073     *  </tr>
    074     *  <tr>
    075     *   <td>""</td>
    076     *   <td>*</td>
    077     *   <td>""</td>
    078     *  </tr>
    079     *  <tr>
    080     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    081     *   <td>20</td>
    082     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
    083     *  </tr>
    084     *  <tr>
    085     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
    086     *   <td>20</td>
    087     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
    088     *  </tr>
    089     *  <tr>
    090     *   <td>"Click here, https://commons.apache.org, to jump to the commons website"</td>
    091     *   <td>20</td>
    092     *   <td>"Click here,\nhttps://commons.apache.org,\nto jump to the\ncommons website"</td>
    093     *  </tr>
    094     * </table>
    095     *
    096     * (assuming that '\n' is the systems line separator)
    097     *
    098     * @param str  the String to be word wrapped, may be null
    099     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
    100     * @return a line with newlines inserted, {@code null} if null input
    101     */
    102    public static String wrap(final String str, final int wrapLength) {
    103        return wrap(str, wrapLength, null, false);
    104    }
    105
    106    /**
    107     * <p>Wraps a single line of text, identifying words by {@code ' '}.</p>
    108     *
    109     * <p>Leading spaces on a new line are stripped.
    110     * Trailing spaces are not stripped.</p>
    111     *
    112     * <table border="1">
    113     *  <caption>Examples</caption>
    114     *  <tr>
    115     *   <th>input</th>
    116     *   <th>wrapLength</th>
    117     *   <th>newLineString</th>
    118     *   <th>wrapLongWords</th>
    119     *   <th>result</th>
    120     *  </tr>
    121     *  <tr>
    122     *   <td>null</td>
    123     *   <td>*</td>
    124     *   <td>*</td>
    125     *   <td>true/false</td>
    126     *   <td>null</td>
    127     *  </tr>
    128     *  <tr>
    129     *   <td>""</td>
    130     *   <td>*</td>
    131     *   <td>*</td>
    132     *   <td>true/false</td>
    133     *   <td>""</td>
    134     *  </tr>
    135     *  <tr>
    136     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    137     *   <td>20</td>
    138     *   <td>"\n"</td>
    139     *   <td>true/false</td>
    140     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
    141     *  </tr>
    142     *  <tr>
    143     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    144     *   <td>20</td>
    145     *   <td>"&lt;br /&gt;"</td>
    146     *   <td>true/false</td>
    147     *   <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>
    148     *  </tr>
    149     *  <tr>
    150     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    151     *   <td>20</td>
    152     *   <td>null</td>
    153     *   <td>true/false</td>
    154     *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
    155     *  </tr>
    156     *  <tr>
    157     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
    158     *   <td>20</td>
    159     *   <td>"\n"</td>
    160     *   <td>false</td>
    161     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
    162     *  </tr>
    163     *  <tr>
    164     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
    165     *   <td>20</td>
    166     *   <td>"\n"</td>
    167     *   <td>true</td>
    168     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"</td>
    169     *  </tr>
    170     * </table>
    171     *
    172     * @param str  the String to be word wrapped, may be null
    173     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
    174     * @param newLineStr  the string to insert for a new line,
    175     *  {@code null} uses the system property line separator
    176     * @param wrapLongWords  true if long words (such as URLs) should be wrapped
    177     * @return a line with newlines inserted, {@code null} if null input
    178     */
    179    public static String wrap(final String str, final int wrapLength, final String newLineStr, final boolean wrapLongWords) {
    180        return wrap(str, wrapLength, newLineStr, wrapLongWords, " ");
    181    }
    182
    183    /**
    184     * <p>Wraps a single line of text, identifying words by {@code wrapOn}.</p>
    185     *
    186     * <p>Leading spaces on a new line are stripped.
    187     * Trailing spaces are not stripped.</p>
    188     *
    189     * <table border="1">
    190     *  <caption>Examples</caption>
    191     *  <tr>
    192     *   <th>input</th>
    193     *   <th>wrapLength</th>
    194     *   <th>newLineString</th>
    195     *   <th>wrapLongWords</th>
    196     *   <th>wrapOn</th>
    197     *   <th>result</th>
    198     *  </tr>
    199     *  <tr>
    200     *   <td>null</td>
    201     *   <td>*</td>
    202     *   <td>*</td>
    203     *   <td>true/false</td>
    204     *   <td>*</td>
    205     *   <td>null</td>
    206     *  </tr>
    207     *  <tr>
    208     *   <td>""</td>
    209     *   <td>*</td>
    210     *   <td>*</td>
    211     *   <td>true/false</td>
    212     *   <td>*</td>
    213     *   <td>""</td>
    214     *  </tr>
    215     *  <tr>
    216     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    217     *   <td>20</td>
    218     *   <td>"\n"</td>
    219     *   <td>true/false</td>
    220     *   <td>" "</td>
    221     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
    222     *  </tr>
    223     *  <tr>
    224     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    225     *   <td>20</td>
    226     *   <td>"&lt;br /&gt;"</td>
    227     *   <td>true/false</td>
    228     *   <td>" "</td>
    229     *   <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>
    230     *  </tr>
    231     *  <tr>
    232     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
    233     *   <td>20</td>
    234     *   <td>null</td>
    235     *   <td>true/false</td>
    236     *   <td>" "</td>
    237     *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
    238     *  </tr>
    239     *  <tr>
    240     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
    241     *   <td>20</td>
    242     *   <td>"\n"</td>
    243     *   <td>false</td>
    244     *   <td>" "</td>
    245     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
    246     *  </tr>
    247     *  <tr>
    248     *   <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
    249     *   <td>20</td>
    250     *   <td>"\n"</td>
    251     *   <td>true</td>
    252     *   <td>" "</td>
    253     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"</td>
    254     *  </tr>
    255     *  <tr>
    256     *   <td>"flammable/inflammable"</td>
    257     *   <td>20</td>
    258     *   <td>"\n"</td>
    259     *   <td>true</td>
    260     *   <td>"/"</td>
    261     *   <td>"flammable\ninflammable"</td>
    262     *  </tr>
    263     * </table>
    264     * @param str  the String to be word wrapped, may be null
    265     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
    266     * @param newLineStr  the string to insert for a new line,
    267     *  {@code null} uses the system property line separator
    268     * @param wrapLongWords  true if long words (such as URLs) should be wrapped
    269     * @param wrapOn regex expression to be used as a breakable characters,
    270     *               if blank string is provided a space character will be used
    271     * @return a line with newlines inserted, {@code null} if null input
    272     */
    273    public static String wrap(final String str, int wrapLength, String newLineStr, final boolean wrapLongWords, String wrapOn) {
    274        if (str == null) {
    275            return null;
    276        }
    277        if (newLineStr == null) {
    278            newLineStr = System.lineSeparator();
    279        }
    280        if (wrapLength < 1) {
    281            wrapLength = 1;
    282        }
    283        if (StringUtils.isBlank(wrapOn)) {
    284            wrapOn = " ";
    285        }
    286        final Pattern patternToWrapOn = Pattern.compile(wrapOn);
    287        final int inputLineLength = str.length();
    288        int offset = 0;
    289        final StringBuilder wrappedLine = new StringBuilder(inputLineLength + 32);
    290
    291        while (offset < inputLineLength) {
    292            int spaceToWrapAt = -1;
    293            Matcher matcher = patternToWrapOn.matcher(
    294                str.substring(offset, Math.min((int) Math.min(Integer.MAX_VALUE, offset + wrapLength + 1L), inputLineLength)));
    295            if (matcher.find()) {
    296                if (matcher.start() == 0) {
    297                    offset += matcher.end();
    298                    continue;
    299                }
    300                spaceToWrapAt = matcher.start() + offset;
    301            }
    302
    303            // only last line without leading spaces is left
    304            if (inputLineLength - offset <= wrapLength) {
    305                break;
    306            }
    307
    308            while (matcher.find()) {
    309                spaceToWrapAt = matcher.start() + offset;
    310            }
    311
    312            if (spaceToWrapAt >= offset) {
    313                // normal case
    314                wrappedLine.append(str, offset, spaceToWrapAt);
    315                wrappedLine.append(newLineStr);
    316                offset = spaceToWrapAt + 1;
    317
    318            } else // really long word or URL
    319            if (wrapLongWords) {
    320                // wrap really long word one line at a time
    321                wrappedLine.append(str, offset, wrapLength + offset);
    322                wrappedLine.append(newLineStr);
    323                offset += wrapLength;
    324            } else {
    325                // do not wrap really long word, just extend beyond limit
    326                matcher = patternToWrapOn.matcher(str.substring(offset + wrapLength));
    327                if (matcher.find()) {
    328                    spaceToWrapAt = matcher.start() + offset + wrapLength;
    329                }
    330
    331                if (spaceToWrapAt >= 0) {
    332                    wrappedLine.append(str, offset, spaceToWrapAt);
    333                    wrappedLine.append(newLineStr);
    334                    offset = spaceToWrapAt + 1;
    335                } else {
    336                    wrappedLine.append(str, offset, str.length());
    337                    offset = inputLineLength;
    338                }
    339            }
    340        }
    341
    342        // Whatever is left in line is short enough to just pass through
    343        wrappedLine.append(str, offset, str.length());
    344
    345        return wrappedLine.toString();
    346    }
    347
    348    // Capitalizing
    349    //-----------------------------------------------------------------------
    350    /**
    351     * <p>Capitalizes all the whitespace separated words in a String.
    352     * Only the first character of each word is changed. To convert the
    353     * rest of each word to lowercase at the same time,
    354     * use {@link #capitalizeFully(String)}.</p>
    355     *
    356     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
    357     * A {@code null} input String returns {@code null}.
    358     * Capitalization uses the Unicode title case, normally equivalent to
    359     * upper case.</p>
    360     *
    361     * <pre>
    362     * WordUtils.capitalize(null)        = null
    363     * WordUtils.capitalize("")          = ""
    364     * WordUtils.capitalize("i am FINE") = "I Am FINE"
    365     * </pre>
    366     *
    367     * @param str  the String to capitalize, may be null
    368     * @return capitalized String, {@code null} if null String input
    369     * @see #uncapitalize(String)
    370     * @see #capitalizeFully(String)
    371     */
    372    public static String capitalize(final String str) {
    373        return capitalize(str, null);
    374    }
    375
    376    /**
    377     * <p>Capitalizes all the delimiter separated words in a String.
    378     * Only the first character of each word is changed. To convert the
    379     * rest of each word to lowercase at the same time,
    380     * use {@link #capitalizeFully(String, char[])}.</p>
    381     *
    382     * <p>The delimiters represent a set of characters understood to separate words.
    383     * The first string character and the first non-delimiter character after a
    384     * delimiter will be capitalized. </p>
    385     *
    386     * <p>A {@code null} input String returns {@code null}.
    387     * Capitalization uses the Unicode title case, normally equivalent to
    388     * upper case.</p>
    389     *
    390     * <pre>
    391     * WordUtils.capitalize(null, *)            = null
    392     * WordUtils.capitalize("", *)              = ""
    393     * WordUtils.capitalize(*, new char[0])     = *
    394     * WordUtils.capitalize("i am fine", null)  = "I Am Fine"
    395     * WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"
    396     * </pre>
    397     *
    398     * @param str  the String to capitalize, may be null
    399     * @param delimiters  set of characters to determine capitalization, null means whitespace
    400     * @return capitalized String, {@code null} if null String input
    401     * @see #uncapitalize(String)
    402     * @see #capitalizeFully(String)
    403     * @since 2.1
    404     */
    405    public static String capitalize(final String str, final char... delimiters) {
    406        final int delimLen = delimiters == null ? -1 : delimiters.length;
    407        if (StringUtils.isEmpty(str) || delimLen == 0) {
    408            return str;
    409        }
    410        final char[] buffer = str.toCharArray();
    411        boolean capitalizeNext = true;
    412        for (int i = 0; i < buffer.length; i++) {
    413            final char ch = buffer[i];
    414            if (isDelimiter(ch, delimiters)) {
    415                capitalizeNext = true;
    416            } else if (capitalizeNext) {
    417                buffer[i] = Character.toTitleCase(ch);
    418                capitalizeNext = false;
    419            }
    420        }
    421        return new String(buffer);
    422    }
    423
    424    //-----------------------------------------------------------------------
    425    /**
    426     * <p>Converts all the whitespace separated words in a String into capitalized words,
    427     * that is each word is made up of a titlecase character and then a series of
    428     * lowercase characters.  </p>
    429     *
    430     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
    431     * A {@code null} input String returns {@code null}.
    432     * Capitalization uses the Unicode title case, normally equivalent to
    433     * upper case.</p>
    434     *
    435     * <pre>
    436     * WordUtils.capitalizeFully(null)        = null
    437     * WordUtils.capitalizeFully("")          = ""
    438     * WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
    439     * </pre>
    440     *
    441     * @param str  the String to capitalize, may be null
    442     * @return capitalized String, {@code null} if null String input
    443     */
    444    public static String capitalizeFully(final String str) {
    445        return capitalizeFully(str, null);
    446    }
    447
    448    /**
    449     * <p>Converts all the delimiter separated words in a String into capitalized words,
    450     * that is each word is made up of a titlecase character and then a series of
    451     * lowercase characters. </p>
    452     *
    453     * <p>The delimiters represent a set of characters understood to separate words.
    454     * The first string character and the first non-delimiter character after a
    455     * delimiter will be capitalized. </p>
    456     *
    457     * <p>A {@code null} input String returns {@code null}.
    458     * Capitalization uses the Unicode title case, normally equivalent to
    459     * upper case.</p>
    460     *
    461     * <pre>
    462     * WordUtils.capitalizeFully(null, *)            = null
    463     * WordUtils.capitalizeFully("", *)              = ""
    464     * WordUtils.capitalizeFully(*, null)            = *
    465     * WordUtils.capitalizeFully(*, new char[0])     = *
    466     * WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"
    467     * </pre>
    468     *
    469     * @param str  the String to capitalize, may be null
    470     * @param delimiters  set of characters to determine capitalization, null means whitespace
    471     * @return capitalized String, {@code null} if null String input
    472     * @since 2.1
    473     */
    474    public static String capitalizeFully(String str, final char... delimiters) {
    475        final int delimLen = delimiters == null ? -1 : delimiters.length;
    476        if (StringUtils.isEmpty(str) || delimLen == 0) {
    477            return str;
    478        }
    479        str = str.toLowerCase();
    480        return capitalize(str, delimiters);
    481    }
    482
    483    //-----------------------------------------------------------------------
    484    /**
    485     * <p>Uncapitalizes all the whitespace separated words in a String.
    486     * Only the first character of each word is changed.</p>
    487     *
    488     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
    489     * A {@code null} input String returns {@code null}.</p>
    490     *
    491     * <pre>
    492     * WordUtils.uncapitalize(null)        = null
    493     * WordUtils.uncapitalize("")          = ""
    494     * WordUtils.uncapitalize("I Am FINE") = "i am fINE"
    495     * </pre>
    496     *
    497     * @param str  the String to uncapitalize, may be null
    498     * @return uncapitalized String, {@code null} if null String input
    499     * @see #capitalize(String)
    500     */
    501    public static String uncapitalize(final String str) {
    502        return uncapitalize(str, null);
    503    }
    504
    505    /**
    506     * <p>Uncapitalizes all the whitespace separated words in a String.
    507     * Only the first character of each word is changed.</p>
    508     *
    509     * <p>The delimiters represent a set of characters understood to separate words.
    510     * The first string character and the first non-delimiter character after a
    511     * delimiter will be uncapitalized. </p>
    512     *
    513     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
    514     * A {@code null} input String returns {@code null}.</p>
    515     *
    516     * <pre>
    517     * WordUtils.uncapitalize(null, *)            = null
    518     * WordUtils.uncapitalize("", *)              = ""
    519     * WordUtils.uncapitalize(*, null)            = *
    520     * WordUtils.uncapitalize(*, new char[0])     = *
    521     * WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"
    522     * </pre>
    523     *
    524     * @param str  the String to uncapitalize, may be null
    525     * @param delimiters  set of characters to determine uncapitalization, null means whitespace
    526     * @return uncapitalized String, {@code null} if null String input
    527     * @see #capitalize(String)
    528     * @since 2.1
    529     */
    530    public static String uncapitalize(final String str, final char... delimiters) {
    531        final int delimLen = delimiters == null ? -1 : delimiters.length;
    532        if (StringUtils.isEmpty(str) || delimLen == 0) {
    533            return str;
    534        }
    535        final char[] buffer = str.toCharArray();
    536        boolean uncapitalizeNext = true;
    537        for (int i = 0; i < buffer.length; i++) {
    538            final char ch = buffer[i];
    539            if (isDelimiter(ch, delimiters)) {
    540                uncapitalizeNext = true;
    541            } else if (uncapitalizeNext) {
    542                buffer[i] = Character.toLowerCase(ch);
    543                uncapitalizeNext = false;
    544            }
    545        }
    546        return new String(buffer);
    547    }
    548
    549    //-----------------------------------------------------------------------
    550    /**
    551     * <p>Swaps the case of a String using a word based algorithm.</p>
    552     *
    553     * <ul>
    554     *  <li>Upper case character converts to Lower case</li>
    555     *  <li>Title case character converts to Lower case</li>
    556     *  <li>Lower case character after Whitespace or at start converts to Title case</li>
    557     *  <li>Other Lower case character converts to Upper case</li>
    558     * </ul>
    559     *
    560     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
    561     * A {@code null} input String returns {@code null}.</p>
    562     *
    563     * <pre>
    564     * StringUtils.swapCase(null)                 = null
    565     * StringUtils.swapCase("")                   = ""
    566     * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
    567     * </pre>
    568     *
    569     * @param str  the String to swap case, may be null
    570     * @return the changed String, {@code null} if null String input
    571     */
    572    public static String swapCase(final String str) {
    573        if (StringUtils.isEmpty(str)) {
    574            return str;
    575        }
    576        final char[] buffer = str.toCharArray();
    577
    578        boolean whitespace = true;
    579
    580        for (int i = 0; i < buffer.length; i++) {
    581            final char ch = buffer[i];
    582            if (Character.isUpperCase(ch) || Character.isTitleCase(ch)) {
    583                buffer[i] = Character.toLowerCase(ch);
    584                whitespace = false;
    585            } else if (Character.isLowerCase(ch)) {
    586                if (whitespace) {
    587                    buffer[i] = Character.toTitleCase(ch);
    588                    whitespace = false;
    589                } else {
    590                    buffer[i] = Character.toUpperCase(ch);
    591                }
    592            } else {
    593                whitespace = Character.isWhitespace(ch);
    594            }
    595        }
    596        return new String(buffer);
    597    }
    598
    599    //-----------------------------------------------------------------------
    600    /**
    601     * <p>Extracts the initial characters from each word in the String.</p>
    602     *
    603     * <p>All first characters after whitespace are returned as a new string.
    604     * Their case is not changed.</p>
    605     *
    606     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
    607     * A {@code null} input String returns {@code null}.</p>
    608     *
    609     * <pre>
    610     * WordUtils.initials(null)             = null
    611     * WordUtils.initials("")               = ""
    612     * WordUtils.initials("Ben John Lee")   = "BJL"
    613     * WordUtils.initials("Ben J.Lee")      = "BJ"
    614     * </pre>
    615     *
    616     * @param str  the String to get initials from, may be null
    617     * @return String of initial letters, {@code null} if null String input
    618     * @see #initials(String,char[])
    619     * @since 2.2
    620     */
    621    public static String initials(final String str) {
    622        return initials(str, null);
    623    }
    624
    625    /**
    626     * <p>Extracts the initial characters from each word in the String.</p>
    627     *
    628     * <p>All first characters after the defined delimiters are returned as a new string.
    629     * Their case is not changed.</p>
    630     *
    631     * <p>If the delimiters array is null, then Whitespace is used.
    632     * Whitespace is defined by {@link Character#isWhitespace(char)}.
    633     * A {@code null} input String returns {@code null}.
    634     * An empty delimiter array returns an empty String.</p>
    635     *
    636     * <pre>
    637     * WordUtils.initials(null, *)                = null
    638     * WordUtils.initials("", *)                  = ""
    639     * WordUtils.initials("Ben John Lee", null)   = "BJL"
    640     * WordUtils.initials("Ben J.Lee", null)      = "BJ"
    641     * WordUtils.initials("Ben J.Lee", [' ','.']) = "BJL"
    642     * WordUtils.initials(*, new char[0])         = ""
    643     * </pre>
    644     *
    645     * @param str  the String to get initials from, may be null
    646     * @param delimiters  set of characters to determine words, null means whitespace
    647     * @return String of initial characters, {@code null} if null String input
    648     * @see #initials(String)
    649     * @since 2.2
    650     */
    651    public static String initials(final String str, final char... delimiters) {
    652        if (StringUtils.isEmpty(str)) {
    653            return str;
    654        }
    655        if (delimiters != null && delimiters.length == 0) {
    656            return StringUtils.EMPTY;
    657        }
    658        final int strLen = str.length();
    659        final char[] buf = new char[strLen / 2 + 1];
    660        int count = 0;
    661        boolean lastWasGap = true;
    662        for (int i = 0; i < strLen; i++) {
    663            final char ch = str.charAt(i);
    664
    665            if (isDelimiter(ch, delimiters)) {
    666                lastWasGap = true;
    667            } else if (lastWasGap) {
    668                buf[count++] = ch;
    669                lastWasGap = false;
    670            } else {
    671                continue; // ignore ch
    672            }
    673        }
    674        return new String(buf, 0, count);
    675    }
    676
    677    //-----------------------------------------------------------------------
    678    /**
    679     * <p>Checks if the String contains all words in the given array.</p>
    680     *
    681     * <p>
    682     * A {@code null} String will return {@code false}. A {@code null}, zero
    683     * length search array or if one element of array is null will return {@code false}.
    684     * </p>
    685     *
    686     * <pre>
    687     * WordUtils.containsAllWords(null, *)            = false
    688     * WordUtils.containsAllWords("", *)              = false
    689     * WordUtils.containsAllWords(*, null)            = false
    690     * WordUtils.containsAllWords(*, [])              = false
    691     * WordUtils.containsAllWords("abcd", "ab", "cd") = false
    692     * WordUtils.containsAllWords("abc def", "def", "abc") = true
    693     * </pre>
    694     *
    695     *
    696     * @param word The CharSequence to check, may be null
    697     * @param words The array of String words to search for, may be null
    698     * @return {@code true} if all search words are found, {@code false} otherwise
    699     * @since 3.5
    700     */
    701    public static boolean containsAllWords(final CharSequence word, final CharSequence... words) {
    702        if (StringUtils.isEmpty(word) || ArrayUtils.isEmpty(words)) {
    703            return false;
    704        }
    705        for (final CharSequence w : words) {
    706            if (StringUtils.isBlank(w)) {
    707                return false;
    708            }
    709            final Pattern p = Pattern.compile(".*\\b" + w + "\\b.*");
    710            if (!p.matcher(word).matches()) {
    711                return false;
    712            }
    713        }
    714        return true;
    715    }
    716
    717    //-----------------------------------------------------------------------
    718    /**
    719     * Is the character a delimiter.
    720     *
    721     * @param ch  the character to check
    722     * @param delimiters  the delimiters
    723     * @return true if it is a delimiter
    724     */
    725    private static boolean isDelimiter(final char ch, final char[] delimiters) {
    726        if (delimiters == null) {
    727            return Character.isWhitespace(ch);
    728        }
    729        for (final char delimiter : delimiters) {
    730            if (ch == delimiter) {
    731                return true;
    732            }
    733        }
    734        return false;
    735    }
    736
    737}