/*
* Copyright 2002-2004 The Apache Software Foundation.
*
* Licensed 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.lang;
/**
* <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>
*
* @author Apache Jakarta Velocity
* @author Henri Yandell
* @author Stephen Colebourne
* @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
* @author Gary Gregory
* @since 2.0
* @version $Id: WordUtils.java,v 1.13 2004/06/04 03:58:27 bayard Exp $
*/
public class WordUtils {
/**
* <p><code>WordWrapUtils</code> instances should NOT be constructed in
* standard programming. Instead, the class should be used as
* <code>WordWrapUtils.wrap("foo bar", 20);</code>.</p>
*
* <p>This constructor is public to permit tools that require a JavaBean
* instance to operate.</p>
*/
public WordUtils() {
}
// Wrapping
//--------------------------------------------------------------------------
// /**
// * <p>Wraps a block of text to a specified line length using '\n' as
// * a newline.</p>
// *
// * <p>This method takes a block of text, which might have long lines in it
// * and wraps the long lines based on the supplied lineLength parameter.</p>
// *
// * <p>If a single word is longer than the line length (eg. a URL), it will
// * not be broken, and will display beyond the expected width.</p>
// *
// * <p>If there are tabs in inString, you are going to get results that are
// * a bit strange. Tabs are a single character but are displayed as 4 or 8
// * spaces. Remove the tabs.</p>
// *
// * @param str text which is in need of word-wrapping, may be null
// * @param lineLength the column to wrap the words at
// * @return the text with all the long lines word-wrapped
// * <code>null</code> if null string input
// */
// public static String wrapText(String str, int lineLength) {
// return wrap(str, null, lineLength);
// }
// /**
// * <p>Wraps a block of text to a specified line length.</p>
// *
// * <p>This method takes a block of text, which might have long lines in it
// * and wraps the long lines based on the supplied lineLength parameter.</p>
// *
// * <p>If a single word is longer than the wrapColumn (eg. a URL), it will
// * not be broken, and will display beyond the expected width.</p>
// *
// * <p>If there are tabs in inString, you are going to get results that are
// * a bit strange. Tabs are a single character but are displayed as 4 or 8
// * spaces. Remove the tabs.</p>
// *
// * @param str text which is in need of word-wrapping, may be null
// * @param newLineChars the characters that define a newline, null treated as \n
// * @param lineLength the column to wrap the words at
// * @return the text with all the long lines word-wrapped
// * <code>null</code> if null string input
// */
// public static String wrapText(String str, String newLineChars, int lineLength) {
// if (str == null) {
// return null;
// }
// if (newLineChars == null) {
// newLineChars = "\n";
// }
// StringTokenizer lineTokenizer = new StringTokenizer(str, newLineChars, true);
// StringBuffer stringBuffer = new StringBuffer();
//
// while (lineTokenizer.hasMoreTokens()) {
// try {
// String nextLine = lineTokenizer.nextToken();
//
// if (nextLine.length() > lineLength) {
// // This line is long enough to be wrapped.
// nextLine = wrapLine(nextLine, null, lineLength, false);
// }
//
// stringBuffer.append(nextLine);
//
// } catch (NoSuchElementException nsee) {
// // thrown by nextToken(), but I don't know why it would
// break;
// }
// }
//
// return (stringBuffer.toString());
// }
// Wrapping
//-----------------------------------------------------------------------
/**
* <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>
*
* <pre>
* WordUtils.wrap(null, *) = null
* WordUtils.wrap("", *) = ""
* </pre>
*
* @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(String str, int wrapLength) {
return wrap(str, wrapLength, null, false);
}
/**
* <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>
*
* <pre>
* WordUtils.wrap(null, *, *, *) = null
* WordUtils.wrap("", *, *, *) = ""
* </pre>
*
* @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(String str, int wrapLength, String newLineStr, boolean wrapLongWords) {
if (str == null) {
return null;
}
if (newLineStr == null) {
newLineStr = SystemUtils.LINE_SEPARATOR;
}
if (wrapLength < 1) {
wrapLength = 1;
}
int inputLineLength = str.length();
int offset = 0;
StringBuffer wrappedLine = new StringBuffer(inputLineLength + 32);
while ((inputLineLength - offset) > wrapLength) {
if (str.charAt(offset) == ' ') {
offset++;
continue;
}
int spaceToWrapAt = str.lastIndexOf(' ', wrapLength + offset);
if (spaceToWrapAt >= offset) {
// normal case
wrappedLine.append(str.substring(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.substring(offset, wrapLength + offset));
wrappedLine.append(newLineStr);
offset += wrapLength;
} else {
// do not wrap really long word, just extend beyond limit
spaceToWrapAt = str.indexOf(' ', wrapLength + offset);
if (spaceToWrapAt >= 0) {
wrappedLine.append(str.substring(offset, spaceToWrapAt));
wrappedLine.append(newLineStr);
offset = spaceToWrapAt + 1;
} else {
wrappedLine.append(str.substring(offset));
offset = inputLineLength;
}
}
}
}
// Whatever is left in line is short enough to just pass through
wrappedLine.append(str.substring(offset));
return wrappedLine.toString();
}
// Capitalizing
//-----------------------------------------------------------------------
/**
* <p>Capitalizes all the whitespace separated words in a String.
* Only the first letter of each word is changed. To change all letters to
* the capitalized case, 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(String str) {
return capitalize(str, null);
}
/**
* <p>Capitalizes all the delimiter separated words in a String.
* Only the first letter of each word is changed. To change all letters to
* the capitalized case, use {@link #capitalizeFully(String)}.</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("i am FINE") = "I Am FINE"
* </pre>
*
* @param str the String to capitalize, may be null
* @param delimiters set of characters to determine capitalization
* @return capitalized String, <code>null</code> if null String input
* @see #uncapitalize(String)
* @see #capitalizeFully(String)
*/
public static String capitalize(String str, char[] delimiters) {
if (str == null || str.length() == 0) {
return str;
}
int strLen = str.length();
StringBuffer buffer = new StringBuffer(strLen);
int delimitersLen = 0;
if(delimiters != null) {
delimitersLen = delimiters.length;
}
boolean capitalizeNext = true;
for (int i = 0; i < strLen; i++) {
char ch = str.charAt(i);
boolean isDelimiter = false;
if(delimiters == null) {
isDelimiter = Character.isWhitespace(ch);
} else {
for(int j=0; j < delimitersLen; j++) {
if(ch == delimiters[j]) {
isDelimiter = true;
break;
}
}
}
if (isDelimiter) {
buffer.append(ch);
capitalizeNext = true;
} else if (capitalizeNext) {
buffer.append(Character.toTitleCase(ch));
capitalizeNext = false;
} else {
buffer.append(ch);
}
}
return buffer.toString();
}
/**
* <p>Capitalizes all the whitespace separated words in a String.
* All letters are changed, so the resulting string will be fully changed.</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
*/
public static String capitalizeFully(String str) {
return capitalizeFully(str, null);
}
/**
* <p>Capitalizes all the delimiter separated words in a String.
* All letters are changed, so the resulting string will be fully 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 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("i am FINE") = "I Am Fine"
* </pre>
*
* @param str the String to capitalize, may be null
* @param delimiters set of characters to determine capitalization
* @return capitalized String, <code>null</code> if null String input
*/
public static String capitalizeFully(String str, char[] delimiters) {
if (str == null || str.length() == 0) {
return str;
}
str = str.toLowerCase();
return capitalize(str, delimiters);
}
/**
* <p>Uncapitalizes all the whitespace separated words in a String.
* Only the first letter 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(String str) {
return uncapitalize(str, null);
}
/**
* <p>Uncapitalizes all the whitespace separated words in a String.
* Only the first letter 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("I Am FINE") = "i am fINE"
* </pre>
*
* @param str the String to uncapitalize, may be null
* @param delimiters set of characters to determine uncapitalization
* @return uncapitalized String, <code>null</code> if null String input
* @see #capitalize(String)
*/
public static String uncapitalize(String str, char[] delimiters) {
if (str == null || str.length() == 0) {
return str;
}
int strLen = str.length();
int delimitersLen = 0;
if(delimiters != null) {
delimitersLen = delimiters.length;
}
StringBuffer buffer = new StringBuffer(strLen);
boolean uncapitalizeNext = true;
for (int i = 0; i < strLen; i++) {
char ch = str.charAt(i);
boolean isDelimiter = false;
if(delimiters == null) {
isDelimiter = Character.isWhitespace(ch);
} else {
for(int j=0; j < delimitersLen; j++) {
if(ch == delimiters[j]) {
isDelimiter = true;
break;
}
}
}
if (isDelimiter) {
buffer.append(ch);
uncapitalizeNext = true;
} else if (uncapitalizeNext) {
buffer.append(Character.toLowerCase(ch));
uncapitalizeNext = false;
} else {
buffer.append(ch);
}
}
return buffer.toString();
}
/**
* <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(String str) {
int strLen;
if (str == null || (strLen = str.length()) == 0) {
return str;
}
StringBuffer buffer = new StringBuffer(strLen);
boolean whitespace = true;
char ch = 0;
char tmp = 0;
for (int i = 0; i < strLen; i++) {
ch = str.charAt(i);
if (Character.isUpperCase(ch)) {
tmp = Character.toLowerCase(ch);
} else if (Character.isTitleCase(ch)) {
tmp = Character.toLowerCase(ch);
} else if (Character.isLowerCase(ch)) {
if (whitespace) {
tmp = Character.toTitleCase(ch);
} else {
tmp = Character.toUpperCase(ch);
}
} else {
tmp = ch;
}
buffer.append(tmp);
whitespace = Character.isWhitespace(ch);
}
return buffer.toString();
}
}
