WordUtils.java
/*
* 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.text;
import java.util.HashSet;
import java.util.Set;
import java.util.function.Predicate;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
/**
* Operations on Strings that contain words.
*
* <p>
* This class tries to handle {@code null} input gracefully. An exception will not be thrown for a
* {@code null} input. Each method documents its behavior in more detail.
* </p>
*
* @since 1.1
*/
public class WordUtils {
/**
* Abbreviates the words nicely.
*
* <p>
* This method searches for the first space after the lower limit and abbreviates
* the String there. It will also append any String passed as a parameter
* to the end of the String. The upper limit can be specified to forcibly
* abbreviate a String.
* </p>
*
* @param str the string to be abbreviated. If null is passed, null is returned.
* If the empty String is passed, the empty string is returned.
* @param lower the lower limit; negative value is treated as zero.
* @param upper the upper limit; specify -1 if no limit is desired.
* The upper limit cannot be lower than the lower limit.
* @param appendToEnd String to be appended to the end of the abbreviated string.
* This is appended ONLY if the string was indeed abbreviated.
* The append does not count towards the lower or upper limits.
* @return The abbreviated String.
*
* <pre>
* WordUtils.abbreviate("Now is the time for all good men", 0, 40, null)); = "Now"
* WordUtils.abbreviate("Now is the time for all good men", 10, 40, null)); = "Now is the"
* WordUtils.abbreviate("Now is the time for all good men", 20, 40, null)); = "Now is the time for all"
* WordUtils.abbreviate("Now is the time for all good men", 0, 40, "")); = "Now"
* WordUtils.abbreviate("Now is the time for all good men", 10, 40, "")); = "Now is the"
* WordUtils.abbreviate("Now is the time for all good men", 20, 40, "")); = "Now is the time for all"
* WordUtils.abbreviate("Now is the time for all good men", 0, 40, " ...")); = "Now ..."
* WordUtils.abbreviate("Now is the time for all good men", 10, 40, " ...")); = "Now is the ..."
* WordUtils.abbreviate("Now is the time for all good men", 20, 40, " ...")); = "Now is the time for all ..."
* WordUtils.abbreviate("Now is the time for all good men", 0, -1, "")); = "Now"
* WordUtils.abbreviate("Now is the time for all good men", 10, -1, "")); = "Now is the"
* WordUtils.abbreviate("Now is the time for all good men", 20, -1, "")); = "Now is the time for all"
* WordUtils.abbreviate("Now is the time for all good men", 50, -1, "")); = "Now is the time for all good men"
* WordUtils.abbreviate("Now is the time for all good men", 1000, -1, "")); = "Now is the time for all good men"
* WordUtils.abbreviate("Now is the time for all good men", 9, -10, null)); = IllegalArgumentException
* WordUtils.abbreviate("Now is the time for all good men", 10, 5, null)); = IllegalArgumentException
* </pre>
*/
public static String abbreviate(final String str, int lower, int upper, final String appendToEnd) {
Validate.isTrue(upper >= -1, "upper value cannot be less than -1");
Validate.isTrue(upper >= lower || upper == -1, "upper value is less than lower value");
if (StringUtils.isEmpty(str)) {
return str;
}
// if the lower value is greater than the length of the string,
// set to the length of the string
if (lower > str.length()) {
lower = str.length();
}
// if the upper value is -1 (i.e. no limit) or is greater
// than the length of the string, set to the length of the string
if (upper == -1 || upper > str.length()) {
upper = str.length();
}
final StringBuilder result = new StringBuilder();
final int index = StringUtils.indexOf(str, " ", lower);
if (index == -1) {
result.append(str, 0, upper);
// only if abbreviation has occurred do we append the appendToEnd value
if (upper != str.length()) {
result.append(StringUtils.defaultString(appendToEnd));
}
} else {
result.append(str, 0, Math.min(index, upper));
result.append(StringUtils.defaultString(appendToEnd));
}
return result.toString();
}
/**
* 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>Whitespace is defined by {@link Character#isWhitespace(char)}.
* A {@code null} input String returns {@code null}.
* 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} 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 {@link #capitalizeFully(String, char[])}.
*
* <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} input String returns {@code null}.
* 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"
* WordUtils.capitalize("i am fine", new char[]{}) = "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} if null String input
* @see #uncapitalize(String)
* @see #capitalizeFully(String)
*/
public static String capitalize(final String str, final char... delimiters) {
if (StringUtils.isEmpty(str)) {
return str;
}
final Predicate<Integer> isDelimiter = generateIsDelimiterFunction(delimiters);
final int strLen = str.length();
final int[] newCodePoints = new int[strLen];
int outOffset = 0;
boolean capitalizeNext = true;
for (int index = 0; index < strLen;) {
final int codePoint = str.codePointAt(index);
if (isDelimiter.test(codePoint)) {
capitalizeNext = true;
newCodePoints[outOffset++] = codePoint;
index += Character.charCount(codePoint);
} else if (capitalizeNext) {
final int titleCaseCodePoint = Character.toTitleCase(codePoint);
newCodePoints[outOffset++] = titleCaseCodePoint;
index += Character.charCount(titleCaseCodePoint);
capitalizeNext = false;
} else {
newCodePoints[outOffset++] = codePoint;
index += Character.charCount(codePoint);
}
}
return new String(newCodePoints, 0, outOffset);
}
/**
* 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>Whitespace is defined by {@link Character#isWhitespace(char)}.
* A {@code null} input String returns {@code null}.
* 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} 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.
*
* <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} input String returns {@code null}.
* 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} if null String input
*/
public static String capitalizeFully(String str, final char... delimiters) {
if (StringUtils.isEmpty(str)) {
return str;
}
str = str.toLowerCase();
return capitalize(str, delimiters);
}
/**
* Checks if the String contains all words in the given array.
*
* <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
*/
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" + Pattern.quote(w.toString()) + "\\b.*");
if (!p.matcher(word).matches()) {
return false;
}
}
return true;
}
/**
* Given the array of delimiters supplied; returns a function determining whether a character code point is a delimiter.
* The function provides O(1) lookup time.
* Whitespace is defined by {@link Character#isWhitespace(char)} and is used as the defaultvalue if delimiters is null.
*
* @param delimiters set of characters to determine delimiters, null means whitespace
* @return Predicate<Integer> taking a code point value as an argument and returning true if a delimiter.
*/
private static Predicate<Integer> generateIsDelimiterFunction(final char[] delimiters) {
final Predicate<Integer> isDelimiter;
if (delimiters == null || delimiters.length == 0) {
isDelimiter = delimiters == null ? Character::isWhitespace : c -> false;
} else {
final Set<Integer> delimiterSet = new HashSet<>();
for (int index = 0; index < delimiters.length; index++) {
delimiterSet.add(Character.codePointAt(delimiters, index));
}
isDelimiter = delimiterSet::contains;
}
return isDelimiter;
}
/**
* Extracts the initial characters from each word in the String.
*
* <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} input String returns {@code null}.</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} if null String input
* @see #initials(String,char[])
*/
public static String initials(final String str) {
return initials(str, null);
}
/**
* Extracts the initial characters from each word in the String.
*
* <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} input String returns {@code null}.
* 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} if null String input
* @see #initials(String)
*/
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 Predicate<Integer> isDelimiter = generateIsDelimiterFunction(delimiters);
final int strLen = str.length();
final int[] newCodePoints = new int[strLen / 2 + 1];
int count = 0;
boolean lastWasGap = true;
for (int i = 0; i < strLen;) {
final int codePoint = str.codePointAt(i);
if (isDelimiter.test(codePoint)) {
lastWasGap = true;
} else if (lastWasGap) {
newCodePoints[count++] = codePoint;
lastWasGap = false;
}
i += Character.charCount(codePoint);
}
return new String(newCodePoints, 0, count);
}
/**
* Is the character a delimiter.
*
* @param ch the character to check
* @param delimiters the delimiters
* @return true if it is a delimiter
* @deprecated as of 1.2 and will be removed in 2.0
*/
@Deprecated
public 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;
}
/**
* Is the codePoint a delimiter.
*
* @param codePoint the codePint to check
* @param delimiters the delimiters
* @return true if it is a delimiter
* @deprecated as of 1.2 and will be removed in 2.0
*/
@Deprecated
public static boolean isDelimiter(final int codePoint, final char[] delimiters) {
if (delimiters == null) {
return Character.isWhitespace(codePoint);
}
for (int index = 0; index < delimiters.length; index++) {
final int delimiterCodePoint = Character.codePointAt(delimiters, index);
if (delimiterCodePoint == codePoint) {
return true;
}
}
return false;
}
/**
* Swaps the case of a String using a word based algorithm.
*
* <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} input String returns {@code null}.</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} if null String input
*/
public static String swapCase(final String str) {
if (StringUtils.isEmpty(str)) {
return str;
}
final int strLen = str.length();
final int[] newCodePoints = new int[strLen];
int outOffset = 0;
boolean whitespace = true;
for (int index = 0; index < strLen;) {
final int oldCodepoint = str.codePointAt(index);
final int newCodePoint;
if (Character.isUpperCase(oldCodepoint) || Character.isTitleCase(oldCodepoint)) {
newCodePoint = Character.toLowerCase(oldCodepoint);
whitespace = false;
} else if (Character.isLowerCase(oldCodepoint)) {
if (whitespace) {
newCodePoint = Character.toTitleCase(oldCodepoint);
whitespace = false;
} else {
newCodePoint = Character.toUpperCase(oldCodepoint);
}
} else {
whitespace = Character.isWhitespace(oldCodepoint);
newCodePoint = oldCodepoint;
}
newCodePoints[outOffset++] = newCodePoint;
index += Character.charCount(newCodePoint);
}
return new String(newCodePoints, 0, outOffset);
}
/**
* Uncapitalizes all the whitespace separated words in a String.
* Only the first character of each word is changed.
*
* <p>Whitespace is defined by {@link Character#isWhitespace(char)}.
* A {@code null} input String returns {@code null}.</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} 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.
*
* <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} input String returns {@code null}.</p>
*
* <pre>
* WordUtils.uncapitalize(null, *) = null
* WordUtils.uncapitalize("", *) = ""
* WordUtils.uncapitalize(*, null) = *
* WordUtils.uncapitalize(*, new char[0]) = *
* WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"
* WordUtils.uncapitalize("I am fine", new char[]{}) = "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} if null String input
* @see #capitalize(String)
*/
public static String uncapitalize(final String str, final char... delimiters) {
if (StringUtils.isEmpty(str)) {
return str;
}
final Predicate<Integer> isDelimiter = generateIsDelimiterFunction(delimiters);
final int strLen = str.length();
final int[] newCodePoints = new int[strLen];
int outOffset = 0;
boolean uncapitalizeNext = true;
for (int index = 0; index < strLen;) {
final int codePoint = str.codePointAt(index);
if (isDelimiter.test(codePoint)) {
uncapitalizeNext = true;
newCodePoints[outOffset++] = codePoint;
index += Character.charCount(codePoint);
} else if (uncapitalizeNext) {
final int titleCaseCodePoint = Character.toLowerCase(codePoint);
newCodePoints[outOffset++] = titleCaseCodePoint;
index += Character.charCount(titleCaseCodePoint);
uncapitalizeNext = false;
} else {
newCodePoints[outOffset++] = codePoint;
index += Character.charCount(codePoint);
}
}
return new String(newCodePoints, 0, outOffset);
}
/**
* Wraps a single line of text, identifying words by {@code ' '}.
*
* <p>New lines will be separated by the system property line separator.
* Very long words, such as URLs will <em>not</em> be wrapped.</p>
*
* <p>Leading spaces on a new line are stripped.
* Trailing spaces are not stripped.</p>
*
* <table border="1">
* <caption>Examples</caption>
* <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 - https://commons.apache.org"</td>
* <td>20</td>
* <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
* </tr>
* <tr>
* <td>"Click here, https://commons.apache.org, to jump to the commons website"</td>
* <td>20</td>
* <td>"Click here,\nhttps://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} 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 {@code ' '}.
*
* <p>Leading spaces on a new line are stripped.
* Trailing spaces are not stripped.</p>
*
* <table border="1">
* <caption>Examples</caption>
* <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>"<br />"</td>
* <td>true/false</td>
* <td>"Here is one line of<br />text that is going<
* br />to be wrapped after<br />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 - https://commons.apache.org"</td>
* <td>20</td>
* <td>"\n"</td>
* <td>false</td>
* <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
* </tr>
* <tr>
* <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
* <td>20</td>
* <td>"\n"</td>
* <td>true</td>
* <td>"Click here to jump\nto the commons\nwebsite -\nhttps://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} 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} 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 {@code wrapOn}.
*
* <p>Leading spaces on a new line are stripped.
* Trailing spaces are not stripped.</p>
*
* <table border="1">
* <caption>Examples</caption>
* <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>"<br />"</td>
* <td>true/false</td>
* <td>" "</td>
* <td>"Here is one line of<br />text that is going<br />
* to be wrapped after<br />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 - https://commons.apache.org"</td>
* <td>20</td>
* <td>"\n"</td>
* <td>false</td>
* <td>" "</td>
* <td>"Click here to jump\nto the commons\nwebsite -\nhttps://commons.apache.org"</td>
* </tr>
* <tr>
* <td>"Click here to jump to the commons website - https://commons.apache.org"</td>
* <td>20</td>
* <td>"\n"</td>
* <td>true</td>
* <td>" "</td>
* <td>"Click here to jump\nto the commons\nwebsite -\nhttps://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} 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} 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);
int matcherSize = -1;
while (offset < inputLineLength) {
int spaceToWrapAt = -1;
Matcher matcher = patternToWrapOn.matcher(str.substring(offset,
Math.min((int) Math.min(Integer.MAX_VALUE, offset + wrapLength + 1L), inputLineLength)));
if (matcher.find()) {
if (matcher.start() == 0) {
matcherSize = matcher.end();
if (matcherSize != 0) {
offset += matcher.end();
continue;
}
offset += 1;
}
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) {
if (matcherSize == 0) {
offset--;
}
// wrap really long word one line at a time
wrappedLine.append(str, offset, wrapLength + offset);
wrappedLine.append(newLineStr);
offset += wrapLength;
matcherSize = -1;
} else {
// do not wrap really long word, just extend beyond limit
matcher = patternToWrapOn.matcher(str.substring(offset + wrapLength));
if (matcher.find()) {
matcherSize = matcher.end() - matcher.start();
spaceToWrapAt = matcher.start() + offset + wrapLength;
}
if (spaceToWrapAt >= 0) {
if (matcherSize == 0 && offset != 0) {
offset--;
}
wrappedLine.append(str, offset, spaceToWrapAt);
wrappedLine.append(newLineStr);
offset = spaceToWrapAt + 1;
} else {
if (matcherSize == 0 && offset != 0) {
offset--;
}
wrappedLine.append(str, offset, str.length());
offset = inputLineLength;
matcherSize = -1;
}
}
}
if (matcherSize == 0 && offset < inputLineLength) {
offset--;
}
// Whatever is left in line is short enough to just pass through
wrappedLine.append(str, offset, str.length());
return wrappedLine.toString();
}
/**
* {@code WordUtils} instances should NOT be constructed in
* standard programming. Instead, the class should be used as
* {@code WordUtils.wrap("foo bar", 20);}.
*
* <p>This constructor is public to permit tools that require a JavaBean
* instance to operate.</p>
*/
public WordUtils() {
}
}