http://commons.apache.org/proper/commons-lang/: Apache Commons Lang, a package of Java utility classes for the classes that are in java.lang's hierarchy, or are considered to be so standard as to justify existence in java.lang. (The Apache Software Foundation)
  • C. Scott Ananian
  • Chris Audley
  • Stephane Bailliez
  • Michael Becke
  • Benjamin Bentmann
  • Ola Berg
  • Nathan Beyer
  • Stefan Bodewig
  • Janek Bogucki
  • Mike Bowler
  • Sean Brown
  • Alexander Day Chaffee
  • Al Chou
  • Greg Coladonato
  • Maarten Coene
  • Justin Couch
  • Michael Davey
  • Norm Deane
  • Morgan Delagrange
  • Ringo De Smet
  • Russel Dittmar
  • Steve Downey
  • Matthias Eichel
  • Christopher Elkins
  • Chris Feldhacker
  • Roland Foerther
  • Pete Gieser
  • Jason Gritman
  • Matthew Hawthorne
  • Michael Heuer
  • Chas Honton
  • Chris Hyzer
  • Paul Jack
  • Marc Johnson
  • Shaun Kalley
  • Tetsuya Kaneuchi
  • Nissim Karpenstein
  • Ed Korthof
  • Holger Krauth
  • Rafal Krupinski
  • Rafal Krzewski
  • David Leppik
  • Eli Lindsey
  • Sven Ludwig
  • Craig R. McClanahan
  • Rand McNeely
  • Hendrik Maryns
  • Dave Meikle
  • Nikolay Metchev
  • Kasper Nielsen
  • Tim O'Brien
  • Brian S O'Neill
  • Andrew C. Oliver
  • Alban Peignier
  • Moritz Petersen
  • Dmitri Plotnikov
  • Neeme Praks
  • Eric Pugh
  • Stephen Putman
  • Travis Reeder
  • Antony Riley
  • Valentin Rocher
  • Scott Sanders
  • James Sawle
  • Ralph Schaer
  • Henning P. Schmiedehausen
  • Sean Schofield
  • Robert Scholte
  • Reuben Sivan
  • Ville Skytta
  • David M. Sledge
  • Michael A. Smith
  • Jan Sorensen
  • Glen Stampoultzis
  • Scott Stanchfield
  • Jon S. Stevens
  • Sean C. Sullivan
  • Ashwin Suresh
  • Helge Tesgaard
  • Arun Mammen Thomas
  • Masato Tezuka
  • Daniel Trebbien
  • Jeff Varszegi
  • Chris Webb
  • Mario Winterer
  • Stepan Koltsov
  • Holger Hoffstatte
  • Derek C. Ashmore
  • Sebastien Riou
  • Allon Mureinik
  • Adam Hooper
  • Chris Karcher
  • Michael Osipov
  • Thiago Andrade
  • Jonathan Baker
  • Mikhail Mazursky
  • Fabian Lange
  • Michał Kordas
  • Felipe Adorno
  • Adrian Ber
  • Mark Dacek
  • Daniel Rall (CollabNet, Inc.)
  • Stephen Colebourne (SITA ATS Ltd)
  • Henri Yandell ()
  • Steven Caswell ()
  • Robert Burrell Donkin ()
  • Gary D. Gregory
  • Fredrik Westermarck ()
  • James Carman (Carman Consulting, Inc.)
  • Niall Pemberton
  • Matt Benson
  • Joerg Schaible
  • Oliver Heger
  • Paul Benedict
  • Benedikt Ritter
  • Duncan Jones
  • Loic Guibert
  • Rob Tompkins 
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.lang3.text;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.StringUtils;


Operations on Strings that contain words.


This class tries to handle null input gracefully.
An exception will not be thrown for a null input.
Each method documents its behaviour in more detail.


Since:2.0
Deprecated:as of 3.6, use commons-text

WordUtils instead
/**
 * <p>Operations on Strings that contain words.</p>
 *
 * <p>This class tries to handle <code>null</code> input gracefully.
 * An exception will not be thrown for a <code>null</code> input.
 * Each method documents its behaviour in more detail.</p>
 *
 * @since 2.0
 * @deprecated as of 3.6, use commons-text
 * <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/WordUtils.html">
 * WordUtils</a> instead
 */
@Deprecated
public class WordUtils {

    
WordUtils instances should NOT be constructed in
standard programming. Instead, the class should be used as
WordUtils.wrap("foo bar", 20);.


This constructor is public to permit tools that require a JavaBean
instance to operate.


/**
     * <p><code>WordUtils</code> instances should NOT be constructed in
     * standard programming. Instead, the class should be used as
     * <code>WordUtils.wrap("foo bar", 20);</code>.</p>
     *
     * <p>This constructor is public to permit tools that require a JavaBean
     * instance to operate.</p>
     */
    public WordUtils() {
      super();
    }

    // Wrapping
    //--------------------------------------------------------------------------
    
Wraps a single line of text, identifying words by ' '.


New lines will be separated by the system property line separator.
Very long words, such as URLs will not be wrapped.


Leading spaces on a new line are stripped.
Trailing spaces are not stripped.



 

  input
  wrapLength
  result
 

 

  null
  *
  null
 

 

  ""
  *
  ""
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  "Here is one line of\ntext that is going\nto be wrapped after\n20 columns."
 

 

  "Click here to jump to the commons website - http://commons.apache.org"
  20
  "Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"
 

 

  "Click here, http://commons.apache.org, to jump to the commons website"
  20
  "Click here,\nhttp://commons.apache.org,\nto jump to the\ncommons website"
 



(assuming that '\n' is the systems line separator)

Params:
  • str –  the String to be word wrapped, may be null
  • wrapLength –  the column to wrap the words at, less than 1 is treated as 1
Returns:a line with newlines inserted, null if null input
/**
     * <p>Wraps a single line of text, identifying words by <code>' '</code>.</p>
     *
     * <p>New lines will be separated by the system property line separator.
     * Very long words, such as URLs will <i>not</i> be wrapped.</p>
     *
     * <p>Leading spaces on a new line are stripped.
     * Trailing spaces are not stripped.</p>
     *
     * <table border="1" summary="Wrap Results">
     *  <tr>
     *   <th>input</th>
     *   <th>wrapLength</th>
     *   <th>result</th>
     *  </tr>
     *  <tr>
     *   <td>null</td>
     *   <td>*</td>
     *   <td>null</td>
     *  </tr>
     *  <tr>
     *   <td>""</td>
     *   <td>*</td>
     *   <td>""</td>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
     *  </tr>
     *  <tr>
     *   <td>"Click here to jump to the commons website - http://commons.apache.org"</td>
     *   <td>20</td>
     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"</td>
     *  </tr>
     *  <tr>
     *   <td>"Click here, http://commons.apache.org, to jump to the commons website"</td>
     *   <td>20</td>
     *   <td>"Click here,\nhttp://commons.apache.org,\nto jump to the\ncommons website"</td>
     *  </tr>
     * </table>
     *
     * (assuming that '\n' is the systems line separator)
     *
     * @param str  the String to be word wrapped, may be null
     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
     * @return a line with newlines inserted, <code>null</code> if null input
     */
    public static String wrap(final String str, final int wrapLength) {
        return wrap(str, wrapLength, null, false);
    }

    
Wraps a single line of text, identifying words by ' '.


Leading spaces on a new line are stripped.
Trailing spaces are not stripped.



 

  input
  wrapLength
  newLineString
  wrapLongWords
  result
 

 

  null
  *
  *
  true/false
  null
 

 

  ""
  *
  *
  true/false
  ""
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  "\n"
  true/false
  "Here is one line of\ntext that is going\nto be wrapped after\n20 columns."
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  "<br />"
  true/false
  "Here is one line of<br />text that is going<br />to be wrapped after<br />20 columns."
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  null
  true/false
  "Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."
 

 

  "Click here to jump to the commons website - http://commons.apache.org"
  20
  "\n"
  false
  "Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"
 

 

  "Click here to jump to the commons website - http://commons.apache.org"
  20
  "\n"
  true
  "Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"
 




Params:
  • str –  the String to be word wrapped, may be null
  • wrapLength –  the column to wrap the words at, less than 1 is treated as 1
  • newLineStr –  the string to insert for a new line,
 null uses the system property line separator
  • wrapLongWords –  true if long words (such as URLs) should be wrapped
Returns:a line with newlines inserted, null if null input
/**
     * <p>Wraps a single line of text, identifying words by <code>' '</code>.</p>
     *
     * <p>Leading spaces on a new line are stripped.
     * Trailing spaces are not stripped.</p>
     *
     * <table border="1" summary="Wrap Results">
     *  <tr>
     *   <th>input</th>
     *   <th>wrapLength</th>
     *   <th>newLineString</th>
     *   <th>wrapLongWords</th>
     *   <th>result</th>
     *  </tr>
     *  <tr>
     *   <td>null</td>
     *   <td>*</td>
     *   <td>*</td>
     *   <td>true/false</td>
     *   <td>null</td>
     *  </tr>
     *  <tr>
     *   <td>""</td>
     *   <td>*</td>
     *   <td>*</td>
     *   <td>true/false</td>
     *   <td>""</td>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>true/false</td>
     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>"&lt;br /&gt;"</td>
     *   <td>true/false</td>
     *   <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>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>null</td>
     *   <td>true/false</td>
     *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
     *  </tr>
     *  <tr>
     *   <td>"Click here to jump to the commons website - http://commons.apache.org"</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>false</td>
     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"</td>
     *  </tr>
     *  <tr>
     *   <td>"Click here to jump to the commons website - http://commons.apache.org"</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>true</td>
     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"</td>
     *  </tr>
     * </table>
     *
     * @param str  the String to be word wrapped, may be null
     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
     * @param newLineStr  the string to insert for a new line,
     *  <code>null</code> uses the system property line separator
     * @param wrapLongWords  true if long words (such as URLs) should be wrapped
     * @return a line with newlines inserted, <code>null</code> if null input
     */
    public static String wrap(final String str, final int wrapLength, final String newLineStr, final boolean wrapLongWords) {
        return wrap(str, wrapLength, newLineStr, wrapLongWords, " ");
    }

    
Wraps a single line of text, identifying words by wrapOn.


Leading spaces on a new line are stripped.
Trailing spaces are not stripped.



 

  input
  wrapLength
  newLineString
  wrapLongWords
  wrapOn
  result
 

 

  null
  *
  *
  true/false
  *
  null
 

 

  ""
  *
  *
  true/false
  *
  ""
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  "\n"
  true/false
  " "
  "Here is one line of\ntext that is going\nto be wrapped after\n20 columns."
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  "<br />"
  true/false
  " "
  "Here is one line of<br />text that is going<br />to be wrapped after<br />20 columns."
 

 

  "Here is one line of text that is going to be wrapped after 20 columns."
  20
  null
  true/false
  " "
  "Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."
 

 

  "Click here to jump to the commons website - http://commons.apache.org"
  20
  "\n"
  false
  " "
  "Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"
 

 

  "Click here to jump to the commons website - http://commons.apache.org"
  20
  "\n"
  true
  " "
  "Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"
 

 

  "flammable/inflammable"
  20
  "\n"
  true
  "/"
  "flammable\ninflammable"
 




Params:
  • str –  the String to be word wrapped, may be null
  • wrapLength –  the column to wrap the words at, less than 1 is treated as 1
  • newLineStr –  the string to insert for a new line,
 null uses the system property line separator
  • wrapLongWords –  true if long words (such as URLs) should be wrapped
  • wrapOn – regex expression to be used as a breakable characters,
              if blank string is provided a space character will be used
Returns:a line with newlines inserted, null if null input
/**
     * <p>Wraps a single line of text, identifying words by <code>wrapOn</code>.</p>
     *
     * <p>Leading spaces on a new line are stripped.
     * Trailing spaces are not stripped.</p>
     *
     * <table border="1" summary="Wrap Results">
     *  <tr>
     *   <th>input</th>
     *   <th>wrapLength</th>
     *   <th>newLineString</th>
     *   <th>wrapLongWords</th>
     *   <th>wrapOn</th>
     *   <th>result</th>
     *  </tr>
     *  <tr>
     *   <td>null</td>
     *   <td>*</td>
     *   <td>*</td>
     *   <td>true/false</td>
     *   <td>*</td>
     *   <td>null</td>
     *  </tr>
     *  <tr>
     *   <td>""</td>
     *   <td>*</td>
     *   <td>*</td>
     *   <td>true/false</td>
     *   <td>*</td>
     *   <td>""</td>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>true/false</td>
     *   <td>" "</td>
     *   <td>"Here is one line of\ntext that is going\nto be wrapped after\n20 columns."</td>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>"&lt;br /&gt;"</td>
     *   <td>true/false</td>
     *   <td>" "</td>
     *   <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>
     *  </tr>
     *  <tr>
     *   <td>"Here is one line of text that is going to be wrapped after 20 columns."</td>
     *   <td>20</td>
     *   <td>null</td>
     *   <td>true/false</td>
     *   <td>" "</td>
     *   <td>"Here is one line of" + systemNewLine + "text that is going" + systemNewLine + "to be wrapped after" + systemNewLine + "20 columns."</td>
     *  </tr>
     *  <tr>
     *   <td>"Click here to jump to the commons website - http://commons.apache.org"</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>false</td>
     *   <td>" "</td>
     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apache.org"</td>
     *  </tr>
     *  <tr>
     *   <td>"Click here to jump to the commons website - http://commons.apache.org"</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>true</td>
     *   <td>" "</td>
     *   <td>"Click here to jump\nto the commons\nwebsite -\nhttp://commons.apach\ne.org"</td>
     *  </tr>
     *  <tr>
     *   <td>"flammable/inflammable"</td>
     *   <td>20</td>
     *   <td>"\n"</td>
     *   <td>true</td>
     *   <td>"/"</td>
     *   <td>"flammable\ninflammable"</td>
     *  </tr>
     * </table>
     * @param str  the String to be word wrapped, may be null
     * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
     * @param newLineStr  the string to insert for a new line,
     *  <code>null</code> uses the system property line separator
     * @param wrapLongWords  true if long words (such as URLs) should be wrapped
     * @param wrapOn regex expression to be used as a breakable characters,
     *               if blank string is provided a space character will be used
     * @return a line with newlines inserted, <code>null</code> if null input
     */
    public static String wrap(final String str, int wrapLength, String newLineStr, final boolean wrapLongWords, String wrapOn) {
        if (str == null) {
            return null;
        }
        if (newLineStr == null) {
            newLineStr = System.lineSeparator();
        }
        if (wrapLength < 1) {
            wrapLength = 1;
        }
        if (StringUtils.isBlank(wrapOn)) {
            wrapOn = " ";
        }
        final Pattern patternToWrapOn = Pattern.compile(wrapOn);
        final int inputLineLength = str.length();
        int offset = 0;
        final StringBuilder wrappedLine = new StringBuilder(inputLineLength + 32);

        while (offset < inputLineLength) {
            int spaceToWrapAt = -1;
            Matcher matcher = patternToWrapOn.matcher(str.substring(offset, Math.min(offset + wrapLength + 1, inputLineLength)));
            if (matcher.find()) {
                if (matcher.start() == 0) {
                    offset += matcher.end();
                    continue;
                }
                spaceToWrapAt = matcher.start() + offset;
            }

            // only last line without leading spaces is left
            if(inputLineLength - offset <= wrapLength) {
                break;
            }

            while(matcher.find()){
                spaceToWrapAt = matcher.start() + offset;
            }

            if (spaceToWrapAt >= offset) {
                // normal case
                wrappedLine.append(str, offset, spaceToWrapAt);
                wrappedLine.append(newLineStr);
                offset = spaceToWrapAt + 1;

            } else {
                // really long word or URL
                if (wrapLongWords) {
                    // wrap really long word one line at a time
                    wrappedLine.append(str, offset, wrapLength + offset);
                    wrappedLine.append(newLineStr);
                    offset += wrapLength;
                } else {
                    // do not wrap really long word, just extend beyond limit
                    matcher = patternToWrapOn.matcher(str.substring(offset + wrapLength));
                    if (matcher.find()) {
                        spaceToWrapAt = matcher.start() + offset + wrapLength;
                    }

                    if (spaceToWrapAt >= 0) {
                        wrappedLine.append(str, offset, spaceToWrapAt);
                        wrappedLine.append(newLineStr);
                        offset = spaceToWrapAt + 1;
                    } else {
                        wrappedLine.append(str, offset, str.length());
                        offset = inputLineLength;
                    }
                }
            }
        }

        // Whatever is left in line is short enough to just pass through
        wrappedLine.append(str, offset, str.length());

        return wrappedLine.toString();
    }

    // Capitalizing
    //-----------------------------------------------------------------------
    
Capitalizes all the whitespace separated words in a String. Only the first character of each word is changed. To convert the rest of each word to lowercase at the same time, use capitalizeFully(String).


Whitespace is defined by Character.isWhitespace(char). A null input String returns null.
Capitalization uses the Unicode title case, normally equivalent to
upper case.


WordUtils.capitalize(null)        = null
WordUtils.capitalize("")          = ""
WordUtils.capitalize("i am FINE") = "I Am FINE"



Params:
  • str –  the String to capitalize, may be null
See Also:
Returns:capitalized String, null if null String input
/**
     * <p>Capitalizes all the whitespace separated words in a String.
     * Only the first character of each word is changed. To convert the
     * rest of each word to lowercase at the same time,
     * use {@link #capitalizeFully(String)}.</p>
     *
     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.
     * Capitalization uses the Unicode title case, normally equivalent to
     * upper case.</p>
     *
     * <pre>
     * WordUtils.capitalize(null)        = null
     * WordUtils.capitalize("")          = ""
     * WordUtils.capitalize("i am FINE") = "I Am FINE"
     * </pre>
     *
     * @param str  the String to capitalize, may be null
     * @return capitalized String, <code>null</code> if null String input
     * @see #uncapitalize(String)
     * @see #capitalizeFully(String)
     */
    public static String capitalize(final String str) {
        return capitalize(str, null);
    }

    
Capitalizes all the delimiter separated words in a String. Only the first character of each word is changed. To convert the rest of each word to lowercase at the same time, use capitalizeFully(String, char[]).


The delimiters represent a set of characters understood to separate words.
The first string character and the first non-delimiter character after a
delimiter will be capitalized. 


A null input String returns null.
Capitalization uses the Unicode title case, normally equivalent to
upper case.


WordUtils.capitalize(null, *)            = null
WordUtils.capitalize("", *)              = ""
WordUtils.capitalize(*, new char[0])     = *
WordUtils.capitalize("i am fine", null)  = "I Am Fine"
WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"



Params:
  • str –  the String to capitalize, may be null
  • delimiters –  set of characters to determine capitalization, null means whitespace
See Also:
Returns:capitalized String, null if null String input
Since:2.1
/**
     * <p>Capitalizes all the delimiter separated words in a String.
     * Only the first character of each word is changed. To convert the
     * rest of each word to lowercase at the same time,
     * use {@link #capitalizeFully(String, char[])}.</p>
     *
     * <p>The delimiters represent a set of characters understood to separate words.
     * The first string character and the first non-delimiter character after a
     * delimiter will be capitalized. </p>
     *
     * <p>A <code>null</code> input String returns <code>null</code>.
     * Capitalization uses the Unicode title case, normally equivalent to
     * upper case.</p>
     *
     * <pre>
     * WordUtils.capitalize(null, *)            = null
     * WordUtils.capitalize("", *)              = ""
     * WordUtils.capitalize(*, new char[0])     = *
     * WordUtils.capitalize("i am fine", null)  = "I Am Fine"
     * WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"
     * </pre>
     *
     * @param str  the String to capitalize, may be null
     * @param delimiters  set of characters to determine capitalization, null means whitespace
     * @return capitalized String, <code>null</code> if null String input
     * @see #uncapitalize(String)
     * @see #capitalizeFully(String)
     * @since 2.1
     */
    public static String capitalize(final String str, final char... delimiters) {
        final int delimLen = delimiters == null ? -1 : delimiters.length;
        if (StringUtils.isEmpty(str) || delimLen == 0) {
            return str;
        }
        final char[] buffer = str.toCharArray();
        boolean capitalizeNext = true;
        for (int i = 0; i < buffer.length; i++) {
            final char ch = buffer[i];
            if (isDelimiter(ch, delimiters)) {
                capitalizeNext = true;
            } else if (capitalizeNext) {
                buffer[i] = Character.toTitleCase(ch);
                capitalizeNext = false;
            }
        }
        return new String(buffer);
    }

    //-----------------------------------------------------------------------
    
Converts all the whitespace separated words in a String into capitalized words,
that is each word is made up of a titlecase character and then a series of
lowercase characters.  


Whitespace is defined by Character.isWhitespace(char). A null input String returns null.
Capitalization uses the Unicode title case, normally equivalent to
upper case.


WordUtils.capitalizeFully(null)        = null
WordUtils.capitalizeFully("")          = ""
WordUtils.capitalizeFully("i am FINE") = "I Am Fine"



Params:
  • str –  the String to capitalize, may be null
Returns:capitalized String, null if null String input
/**
     * <p>Converts all the whitespace separated words in a String into capitalized words,
     * that is each word is made up of a titlecase character and then a series of
     * lowercase characters.  </p>
     *
     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.
     * Capitalization uses the Unicode title case, normally equivalent to
     * upper case.</p>
     *
     * <pre>
     * WordUtils.capitalizeFully(null)        = null
     * WordUtils.capitalizeFully("")          = ""
     * WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
     * </pre>
     *
     * @param str  the String to capitalize, may be null
     * @return capitalized String, <code>null</code> if null String input
     */
    public static String capitalizeFully(final String str) {
        return capitalizeFully(str, null);
    }

    
Converts all the delimiter separated words in a String into capitalized words,
that is each word is made up of a titlecase character and then a series of
lowercase characters. 


The delimiters represent a set of characters understood to separate words.
The first string character and the first non-delimiter character after a
delimiter will be capitalized. 


A null input String returns null.
Capitalization uses the Unicode title case, normally equivalent to
upper case.


WordUtils.capitalizeFully(null, *)            = null
WordUtils.capitalizeFully("", *)              = ""
WordUtils.capitalizeFully(*, null)            = *
WordUtils.capitalizeFully(*, new char[0])     = *
WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"



Params:
  • str –  the String to capitalize, may be null
  • delimiters –  set of characters to determine capitalization, null means whitespace
Returns:capitalized String, null if null String input
Since:2.1
/**
     * <p>Converts all the delimiter separated words in a String into capitalized words,
     * that is each word is made up of a titlecase character and then a series of
     * lowercase characters. </p>
     *
     * <p>The delimiters represent a set of characters understood to separate words.
     * The first string character and the first non-delimiter character after a
     * delimiter will be capitalized. </p>
     *
     * <p>A <code>null</code> input String returns <code>null</code>.
     * Capitalization uses the Unicode title case, normally equivalent to
     * upper case.</p>
     *
     * <pre>
     * WordUtils.capitalizeFully(null, *)            = null
     * WordUtils.capitalizeFully("", *)              = ""
     * WordUtils.capitalizeFully(*, null)            = *
     * WordUtils.capitalizeFully(*, new char[0])     = *
     * WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"
     * </pre>
     *
     * @param str  the String to capitalize, may be null
     * @param delimiters  set of characters to determine capitalization, null means whitespace
     * @return capitalized String, <code>null</code> if null String input
     * @since 2.1
     */
    public static String capitalizeFully(String str, final char... delimiters) {
        final int delimLen = delimiters == null ? -1 : delimiters.length;
        if (StringUtils.isEmpty(str) || delimLen == 0) {
            return str;
        }
        str = str.toLowerCase();
        return capitalize(str, delimiters);
    }

    //-----------------------------------------------------------------------
    
Uncapitalizes all the whitespace separated words in a String.
Only the first character of each word is changed.


Whitespace is defined by Character.isWhitespace(char). A null input String returns null.


WordUtils.uncapitalize(null)        = null
WordUtils.uncapitalize("")          = ""
WordUtils.uncapitalize("I Am FINE") = "i am fINE"



Params:
  • str –  the String to uncapitalize, may be null
See Also:
Returns:uncapitalized String, null if null String input
/**
     * <p>Uncapitalizes all the whitespace separated words in a String.
     * Only the first character of each word is changed.</p>
     *
     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.</p>
     *
     * <pre>
     * WordUtils.uncapitalize(null)        = null
     * WordUtils.uncapitalize("")          = ""
     * WordUtils.uncapitalize("I Am FINE") = "i am fINE"
     * </pre>
     *
     * @param str  the String to uncapitalize, may be null
     * @return uncapitalized String, <code>null</code> if null String input
     * @see #capitalize(String)
     */
    public static String uncapitalize(final String str) {
        return uncapitalize(str, null);
    }

    
Uncapitalizes all the whitespace separated words in a String.
Only the first character of each word is changed.


The delimiters represent a set of characters understood to separate words.
The first string character and the first non-delimiter character after a
delimiter will be uncapitalized. 


Whitespace is defined by Character.isWhitespace(char). A null input String returns null.


WordUtils.uncapitalize(null, *)            = null
WordUtils.uncapitalize("", *)              = ""
WordUtils.uncapitalize(*, null)            = *
WordUtils.uncapitalize(*, new char[0])     = *
WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"



Params:
  • str –  the String to uncapitalize, may be null
  • delimiters –  set of characters to determine uncapitalization, null means whitespace
See Also:
Returns:uncapitalized String, null if null String input
Since:2.1
/**
     * <p>Uncapitalizes all the whitespace separated words in a String.
     * Only the first character of each word is changed.</p>
     *
     * <p>The delimiters represent a set of characters understood to separate words.
     * The first string character and the first non-delimiter character after a
     * delimiter will be uncapitalized. </p>
     *
     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.</p>
     *
     * <pre>
     * WordUtils.uncapitalize(null, *)            = null
     * WordUtils.uncapitalize("", *)              = ""
     * WordUtils.uncapitalize(*, null)            = *
     * WordUtils.uncapitalize(*, new char[0])     = *
     * WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"
     * </pre>
     *
     * @param str  the String to uncapitalize, may be null
     * @param delimiters  set of characters to determine uncapitalization, null means whitespace
     * @return uncapitalized String, <code>null</code> if null String input
     * @see #capitalize(String)
     * @since 2.1
     */
    public static String uncapitalize(final String str, final char... delimiters) {
        final int delimLen = delimiters == null ? -1 : delimiters.length;
        if (StringUtils.isEmpty(str) || delimLen == 0) {
            return str;
        }
        final char[] buffer = str.toCharArray();
        boolean uncapitalizeNext = true;
        for (int i = 0; i < buffer.length; i++) {
            final char ch = buffer[i];
            if (isDelimiter(ch, delimiters)) {
                uncapitalizeNext = true;
            } else if (uncapitalizeNext) {
                buffer[i] = Character.toLowerCase(ch);
                uncapitalizeNext = false;
            }
        }
        return new String(buffer);
    }

    //-----------------------------------------------------------------------
    
Swaps the case of a String using a word based algorithm.


    
 
  • Upper case character converts to Lower case
    • 
 
  • Title case character converts to Lower case
    • 
 
  • Lower case character after Whitespace or at start converts to Title case
    • 
 
  • Other Lower case character converts to Upper case
    • 



Whitespace is defined by Character.isWhitespace(char). A null input String returns null.


StringUtils.swapCase(null)                 = null
StringUtils.swapCase("")                   = ""
StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"



Params:
  • str –  the String to swap case, may be null
Returns:the changed String, null if null String input
/**
     * <p>Swaps the case of a String using a word based algorithm.</p>
     *
     * <ul>
     *  <li>Upper case character converts to Lower case</li>
     *  <li>Title case character converts to Lower case</li>
     *  <li>Lower case character after Whitespace or at start converts to Title case</li>
     *  <li>Other Lower case character converts to Upper case</li>
     * </ul>
     *
     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.</p>
     *
     * <pre>
     * StringUtils.swapCase(null)                 = null
     * StringUtils.swapCase("")                   = ""
     * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
     * </pre>
     *
     * @param str  the String to swap case, may be null
     * @return the changed String, <code>null</code> if null String input
     */
    public static String swapCase(final String str) {
        if (StringUtils.isEmpty(str)) {
            return str;
        }
        final char[] buffer = str.toCharArray();

        boolean whitespace = true;

        for (int i = 0; i < buffer.length; i++) {
            final char ch = buffer[i];
            if (Character.isUpperCase(ch)) {
                buffer[i] = Character.toLowerCase(ch);
                whitespace = false;
            } else if (Character.isTitleCase(ch)) {
                buffer[i] = Character.toLowerCase(ch);
                whitespace = false;
            } else if (Character.isLowerCase(ch)) {
                if (whitespace) {
                    buffer[i] = Character.toTitleCase(ch);
                    whitespace = false;
                } else {
                    buffer[i] = Character.toUpperCase(ch);
                }
            } else {
                whitespace = Character.isWhitespace(ch);
            }
        }
        return new String(buffer);
    }

    //-----------------------------------------------------------------------
    
Extracts the initial characters from each word in the String.


All first characters after whitespace are returned as a new string.
Their case is not changed.


Whitespace is defined by Character.isWhitespace(char). A null input String returns null.


WordUtils.initials(null)             = null
WordUtils.initials("")               = ""
WordUtils.initials("Ben John Lee")   = "BJL"
WordUtils.initials("Ben J.Lee")      = "BJ"



Params:
  • str –  the String to get initials from, may be null
See Also:
Returns:String of initial letters, null if null String input
Since:2.2
/**
     * <p>Extracts the initial characters from each word in the String.</p>
     *
     * <p>All first characters after whitespace are returned as a new string.
     * Their case is not changed.</p>
     *
     * <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.</p>
     *
     * <pre>
     * WordUtils.initials(null)             = null
     * WordUtils.initials("")               = ""
     * WordUtils.initials("Ben John Lee")   = "BJL"
     * WordUtils.initials("Ben J.Lee")      = "BJ"
     * </pre>
     *
     * @param str  the String to get initials from, may be null
     * @return String of initial letters, <code>null</code> if null String input
     * @see #initials(String,char[])
     * @since 2.2
     */
    public static String initials(final String str) {
        return initials(str, null);
    }

    
Extracts the initial characters from each word in the String.


All first characters after the defined delimiters are returned as a new string.
Their case is not changed.


If the delimiters array is null, then Whitespace is used. Whitespace is defined by Character.isWhitespace(char). A null input String returns null.
An empty delimiter array returns an empty String.


WordUtils.initials(null, *)                = null
WordUtils.initials("", *)                  = ""
WordUtils.initials("Ben John Lee", null)   = "BJL"
WordUtils.initials("Ben J.Lee", null)      = "BJ"
WordUtils.initials("Ben J.Lee", [' ','.']) = "BJL"
WordUtils.initials(*, new char[0])         = ""



Params:
  • str –  the String to get initials from, may be null
  • delimiters –  set of characters to determine words, null means whitespace
See Also:
Returns:String of initial characters, null if null String input
Since:2.2
/**
     * <p>Extracts the initial characters from each word in the String.</p>
     *
     * <p>All first characters after the defined delimiters are returned as a new string.
     * Their case is not changed.</p>
     *
     * <p>If the delimiters array is null, then Whitespace is used.
     * Whitespace is defined by {@link Character#isWhitespace(char)}.
     * A <code>null</code> input String returns <code>null</code>.
     * An empty delimiter array returns an empty String.</p>
     *
     * <pre>
     * WordUtils.initials(null, *)                = null
     * WordUtils.initials("", *)                  = ""
     * WordUtils.initials("Ben John Lee", null)   = "BJL"
     * WordUtils.initials("Ben J.Lee", null)      = "BJ"
     * WordUtils.initials("Ben J.Lee", [' ','.']) = "BJL"
     * WordUtils.initials(*, new char[0])         = ""
     * </pre>
     *
     * @param str  the String to get initials from, may be null
     * @param delimiters  set of characters to determine words, null means whitespace
     * @return String of initial characters, <code>null</code> if null String input
     * @see #initials(String)
     * @since 2.2
     */
    public static String initials(final String str, final char... delimiters) {
        if (StringUtils.isEmpty(str)) {
            return str;
        }
        if (delimiters != null && delimiters.length == 0) {
            return StringUtils.EMPTY;
        }
        final int strLen = str.length();
        final char[] buf = new char[strLen / 2 + 1];
        int count = 0;
        boolean lastWasGap = true;
        for (int i = 0; i < strLen; i++) {
            final char ch = str.charAt(i);

            if (isDelimiter(ch, delimiters)) {
                lastWasGap = true;
            } else if (lastWasGap) {
                buf[count++] = ch;
                lastWasGap = false;
            } else {
                continue; // ignore ch
            }
        }
        return new String(buf, 0, count);
    }

    //-----------------------------------------------------------------------
    
Checks if the String contains all words in the given array.


 A null String will return false. A null, zero length search array or if one element of array is null will return false. 


WordUtils.containsAllWords(null, *)            = false
WordUtils.containsAllWords("", *)              = false
WordUtils.containsAllWords(*, null)            = false
WordUtils.containsAllWords(*, [])              = false
WordUtils.containsAllWords("abcd", "ab", "cd") = false
WordUtils.containsAllWords("abc def", "def", "abc") = true



Params:
  • word – The CharSequence to check, may be null
  • words – The array of String words to search for, may be null
Returns:true if all search words are found, false otherwise
Since:3.5
/**
     * <p>Checks if the String contains all words in the given array.</p>
     *
     * <p>
     * A {@code null} String will return {@code false}. A {@code null}, zero
     * length search array or if one element of array is null will return {@code false}.
     * </p>
     *
     * <pre>
     * WordUtils.containsAllWords(null, *)            = false
     * WordUtils.containsAllWords("", *)              = false
     * WordUtils.containsAllWords(*, null)            = false
     * WordUtils.containsAllWords(*, [])              = false
     * WordUtils.containsAllWords("abcd", "ab", "cd") = false
     * WordUtils.containsAllWords("abc def", "def", "abc") = true
     * </pre>
     *
     *
     * @param word The CharSequence to check, may be null
     * @param words The array of String words to search for, may be null
     * @return {@code true} if all search words are found, {@code false} otherwise
     * @since 3.5
     */
    public static boolean containsAllWords(final CharSequence word, final CharSequence... words) {
        if (StringUtils.isEmpty(word) || ArrayUtils.isEmpty(words)) {
            return false;
        }
        for (final CharSequence w : words) {
            if (StringUtils.isBlank(w)) {
                return false;
            }
            final Pattern p = Pattern.compile(".*\\b" + w + "\\b.*");
            if (!p.matcher(word).matches()) {
                return false;
            }
        }
        return true;
    }

    //-----------------------------------------------------------------------
    
Is the character a delimiter.

Params:
  • ch –  the character to check
  • delimiters –  the delimiters
Returns:true if it is a delimiter
/**
     * Is the character a delimiter.
     *
     * @param ch  the character to check
     * @param delimiters  the delimiters
     * @return true if it is a delimiter
     */
    private static boolean isDelimiter(final char ch, final char[] delimiters) {
        if (delimiters == null) {
            return Character.isWhitespace(ch);
        }
        for (final char delimiter : delimiters) {
            if (ch == delimiter) {
                return true;
            }
        }
        return false;
    }

}