org.apache.commons.lang

Class CharUtils

public class CharUtils extends Object

Operations on char primitives and Character objects.

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: 2.1

Version: $Id: CharUtils.java 437554 2006-08-28 06:21:41Z bayard $

Author: Stephen Colebourne

Field Summary
static char	CR carriage return CR ('\r').
static char	LF linefeed LF ('\n').

Constructor Summary
	CharUtils() `CharUtils` instances should NOT be constructed in standard programming.

Method Summary
static boolean	isAscii(char ch) Checks whether the character is ASCII 7 bit. CharUtils.isAscii('a') = true CharUtils.isAscii('A') = true CharUtils.isAscii('3') = true CharUtils.isAscii('-') = true CharUtils.isAscii('\n') = true CharUtils.isAscii('©') = false
static boolean	isAsciiAlpha(char ch) Checks whether the character is ASCII 7 bit alphabetic. CharUtils.isAsciiAlpha('a') = true CharUtils.isAsciiAlpha('A') = true CharUtils.isAsciiAlpha('3') = false CharUtils.isAsciiAlpha('-') = false CharUtils.isAsciiAlpha('\n') = false CharUtils.isAsciiAlpha('©') = false
static boolean	isAsciiAlphaLower(char ch) Checks whether the character is ASCII 7 bit alphabetic lower case. CharUtils.isAsciiAlphaLower('a') = true CharUtils.isAsciiAlphaLower('A') = false CharUtils.isAsciiAlphaLower('3') = false CharUtils.isAsciiAlphaLower('-') = false CharUtils.isAsciiAlphaLower('\n') = false CharUtils.isAsciiAlphaLower('©') = false
static boolean	isAsciiAlphanumeric(char ch) Checks whether the character is ASCII 7 bit numeric. CharUtils.isAsciiAlphanumeric('a') = true CharUtils.isAsciiAlphanumeric('A') = true CharUtils.isAsciiAlphanumeric('3') = true CharUtils.isAsciiAlphanumeric('-') = false CharUtils.isAsciiAlphanumeric('\n') = false CharUtils.isAsciiAlphanumeric('©') = false
static boolean	isAsciiAlphaUpper(char ch) Checks whether the character is ASCII 7 bit alphabetic upper case. CharUtils.isAsciiAlphaUpper('a') = false CharUtils.isAsciiAlphaUpper('A') = true CharUtils.isAsciiAlphaUpper('3') = false CharUtils.isAsciiAlphaUpper('-') = false CharUtils.isAsciiAlphaUpper('\n') = false CharUtils.isAsciiAlphaUpper('©') = false
static boolean	isAsciiControl(char ch) Checks whether the character is ASCII 7 bit control. CharUtils.isAsciiControl('a') = false CharUtils.isAsciiControl('A') = false CharUtils.isAsciiControl('3') = false CharUtils.isAsciiControl('-') = false CharUtils.isAsciiControl('\n') = true CharUtils.isAsciiControl('©') = false
static boolean	isAsciiNumeric(char ch) Checks whether the character is ASCII 7 bit numeric. CharUtils.isAsciiNumeric('a') = false CharUtils.isAsciiNumeric('A') = false CharUtils.isAsciiNumeric('3') = true CharUtils.isAsciiNumeric('-') = false CharUtils.isAsciiNumeric('\n') = false CharUtils.isAsciiNumeric('©') = false
static boolean	isAsciiPrintable(char ch) Checks whether the character is ASCII 7 bit printable. CharUtils.isAsciiPrintable('a') = true CharUtils.isAsciiPrintable('A') = true CharUtils.isAsciiPrintable('3') = true CharUtils.isAsciiPrintable('-') = true CharUtils.isAsciiPrintable('\n') = false CharUtils.isAsciiPrintable('©') = false
static char	toChar(Character ch) Converts the Character to a char throwing an exception for `null`. CharUtils.toChar(null) = IllegalArgumentException CharUtils.toChar(' ') = ' ' CharUtils.toChar('A') = 'A'
static char	toChar(Character ch, char defaultValue) Converts the Character to a char handling `null`. CharUtils.toChar(null, 'X') = 'X' CharUtils.toChar(' ', 'X') = ' ' CharUtils.toChar('A', 'X') = 'A'
static char	toChar(String str) Converts the String to a char using the first character, throwing an exception on empty Strings. CharUtils.toChar(null) = IllegalArgumentException CharUtils.toChar("") = IllegalArgumentException CharUtils.toChar("A") = 'A' CharUtils.toChar("BA") = 'B'
static char	toChar(String str, char defaultValue) Converts the String to a char using the first character, defaulting the value on empty Strings. CharUtils.toChar(null, 'X') = 'X' CharUtils.toChar("", 'X') = 'X' CharUtils.toChar("A", 'X') = 'A' CharUtils.toChar("BA", 'X') = 'B'
static Character	toCharacterObject(char ch) Converts the character to a Character. For ASCII 7 bit characters, this uses a cache that will return the same Character object each time. CharUtils.toCharacterObject(' ') = ' ' CharUtils.toCharacterObject('A') = 'A'
static Character	toCharacterObject(String str) Converts the String to a Character using the first character, returning null for empty Strings. For ASCII 7 bit characters, this uses a cache that will return the same Character object each time. CharUtils.toCharacterObject(null) = null CharUtils.toCharacterObject("") = null CharUtils.toCharacterObject("A") = 'A' CharUtils.toCharacterObject("BA") = 'B'
static int	toIntValue(char ch) Converts the character to the Integer it represents, throwing an exception if the character is not numeric. This method coverts the char '1' to the int 1 and so on. CharUtils.toIntValue('3') = 3 CharUtils.toIntValue('A') = IllegalArgumentException
static int	toIntValue(char ch, int defaultValue) Converts the character to the Integer it represents, throwing an exception if the character is not numeric. This method coverts the char '1' to the int 1 and so on. CharUtils.toIntValue('3', -1) = 3 CharUtils.toIntValue('A', -1) = -1
static int	toIntValue(Character ch) Converts the character to the Integer it represents, throwing an exception if the character is not numeric. This method coverts the char '1' to the int 1 and so on. CharUtils.toIntValue(null) = IllegalArgumentException CharUtils.toIntValue('3') = 3 CharUtils.toIntValue('A') = IllegalArgumentException
static int	toIntValue(Character ch, int defaultValue) Converts the character to the Integer it represents, throwing an exception if the character is not numeric. This method coverts the char '1' to the int 1 and so on. CharUtils.toIntValue(null, -1) = -1 CharUtils.toIntValue('3', -1) = 3 CharUtils.toIntValue('A', -1) = -1
static String	toString(char ch) Converts the character to a String that contains the one character. For ASCII 7 bit characters, this uses a cache that will return the same String object each time. CharUtils.toString(' ') = " " CharUtils.toString('A') = "A"
static String	toString(Character ch) Converts the character to a String that contains the one character. For ASCII 7 bit characters, this uses a cache that will return the same String object each time. If `null` is passed in, `null` will be returned. CharUtils.toString(null) = null CharUtils.toString(' ') = " " CharUtils.toString('A') = "A"
static String	unicodeEscaped(char ch) Converts the string to the unicode format ' '. This format is the Java source code format. CharUtils.unicodeEscaped(' ') = " " CharUtils.unicodeEscaped('A') = "A"
static String	unicodeEscaped(Character ch) Converts the string to the unicode format ' '. This format is the Java source code format. If `null` is passed in, `null` will be returned. CharUtils.unicodeEscaped(null) = null CharUtils.unicodeEscaped(' ') = " " CharUtils.unicodeEscaped('A') = "A"

Field Detail

CR

public static final char CR

carriage return CR ('\r').

Since: 2.2

LF

public static final char LF

linefeed LF ('\n').

Since: 2.2

Constructor Detail

CharUtils

public CharUtils()

CharUtils instances should NOT be constructed in standard programming. Instead, the class should be used as CharUtils.toString('c');.

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

Method Detail