Java

java.lang.Character Class & Methods

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The java.lang.Character class wraps a value of the primitive type char in an object. An object of type Character contains a single field whose type is char.  This class provides several methods for determining a character’s category (lowercase letter, digit, etc.) and for converting characters from uppercase to lowercase and vice versa.

Character information is based on the Unicode Standard. The methods and data of class Character are defined by the information in the UnicodeData file that is part of the Unicode Character Database maintained by the Unicode Consortium. This file specifies various properties including name and general category for every defined Unicode code point or character range.

Character class implements Comparable Interface that’s help while sorting list of Objects on natural order.

See Also:

Sub Class

  • static class Character.Subset :Instances of this class represent particular subsets of the Unicode character set.
  • static class Character.UnicodeBlock :A family of character subsets representing the charater blocks in the Unicode specification.
  • static class Character.UnicodeScript :A family of character subsets representing the character scripts defined in the Unicode Standard Annex #24: Script Names.

Constants

  • static byte COMBINING_SPACING_MARK :General category “Mc” in the Unicode specification.
  • static byte CONNECTOR_PUNCTUATION :General category “Pc” in the Unicode specification.
  • static byte CONTROL :General category “Cc” in the Unicode specification.
  • static byte CURRENCY_SYMBOL :General category “Sc” in the Unicode specification.
  • static byte DASH_PUNCTUATION :General category “Pd” in the Unicode specification.
  • static byte DECIMAL_DIGIT_NUMBER :General category “Nd” in the Unicode specification.
  • static byte DIRECTIONALITY_ARABIC_NUMBER :Weak bidirectional character type “AN” in the Unicode specification.
  • static byte DIRECTIONALITY_BOUNDARY_NEUTRAL :Weak bidirectional character type “BN” in the Unicode specification.
  • static byte DIRECTIONALITY_COMMON_NUMBER_SEPARATOR :Weak bidirectional character type “CS” in the Unicode specification.
  • static byte DIRECTIONALITY_EUROPEAN_NUMBER :Weak bidirectional character type “EN” in the Unicode specification.
  • static byte DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR :Weak bidirectional character type “ES” in the Unicode specification.
  • static byte DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR :Weak bidirectional character type “ET” in the Unicode specification.
  • static byte DIRECTIONALITY_LEFT_TO_RIGHT :Strong bidirectional character type “L” in the Unicode specification.
  • static byte DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING :Strong bidirectional character type “LRE” in the Unicode specification.
  • static byte DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE :Strong bidirectional character type “LRO” in the Unicode specification.
  • static byte DIRECTIONALITY_NONSPACING_MARK :Weak bidirectional character type “NSM” in the Unicode specification.
  • static byte DIRECTIONALITY_OTHER_NEUTRALS :Neutral bidirectional character type “ON” in the Unicode specification.
  • static byte DIRECTIONALITY_PARAGRAPH_SEPARATOR :Neutral bidirectional character type “B” in the Unicode specification.
  • static byte DIRECTIONALITY_POP_DIRECTIONAL_FORMAT :Weak bidirectional character type “PDF” in the Unicode specification.
  • static byte DIRECTIONALITY_RIGHT_TO_LEFT :Strong bidirectional character type “R” in the Unicode specification.
  • static byte DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC :Strong bidirectional character type “AL” in the Unicode specification.\
  • static byte DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING :Strong bidirectional character type “RLE” in the Unicode specification.
  • static byte DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE :Strong bidirectional character type “RLO” in the Unicode specification.
  • static byte DIRECTIONALITY_SEGMENT_SEPARATOR :Neutral bidirectional character type “S” in the Unicode specification.
  • static byte DIRECTIONALITY_UNDEFINED :Undefined bidirectional character type.
  • static byte DIRECTIONALITY_WHITESPACE :Neutral bidirectional character type “WS” in the Unicode specification.
  • static byte ENCLOSING_MARK :General category “Me” in the Unicode specification.
  • static byte END_PUNCTUATION :General category “Pe” in the Unicode specification.
  • static byte FINAL_QUOTE_PUNCTUATION :General category “Pf” in the Unicode specification.
  • static byte FORMAT :General category “Cf” in the Unicode specification.
  • static byte INITIAL_QUOTE_PUNCTUATION :General category “Pi” in the Unicode specification.
  • static byte LETTER_NUMBER :General category “Nl” in the Unicode specification.
  • static byte LINE_SEPARATOR :General category “Zl” in the Unicode specification.
  • static byte LOWERCASE_LETTER :General category “Ll” in the Unicode specification.
  • static byte MATH_SYMBOL :General category “Sm” in the Unicode specification.
  • static int MAX_CODE_POINT :The maximum value of a Unicode code point, constant U+10FFFF.
  • static char MAX_HIGH_SURROGATE :The maximum value of a Unicode high-surrogate code unit in the UTF-16 encoding, constant ‘\uDBFF’.
  • static char MAX_LOW_SURROGATE :The maximum value of a Unicode low-surrogate code unit in the UTF-16 encoding, constant ‘\uDFFF’.
  • static int MAX_RADIX :The maximum radix available for conversion to and from strings.
  • static char MAX_SURROGATE :The maximum value of a Unicode surrogate code unit in the UTF-16 encoding, constant ‘\uDFFF’.
  • static char MAX_VALUE :The constant value of this field is the largest value of type char, ‘\uFFFF’.
  • static int MIN_CODE_POINT :The minimum value of a Unicode code point, constant U+0000.
  • static char MIN_HIGH_SURROGATE :The minimum value of a Unicode high-surrogate code unit in the UTF-16 encoding, constant ‘\uD800’.
  • static char MIN_LOW_SURROGATE :The minimum value of a Unicode low-surrogate code unit in the UTF-16 encoding, constant ‘\uDC00’.
  • static int MIN_RADIX :The minimum radix available for conversion to and from strings.
  • static int MIN_SUPPLEMENTARY_CODE_POINT :The minimum value of a Unicode supplementary code point, constant U+10000.
  • static char MIN_SURROGATE :The minimum value of a Unicode surrogate code unit in the UTF-16 encoding, constant ‘\uD800’.
  • static char MIN_VALUE :The constant value of this field is the smallest value of type char, ‘\u0000’.
  • static byte MODIFIER_LETTER :General category “Lm” in the Unicode specification.
  • static byte MODIFIER_SYMBOL :General category “Sk” in the Unicode specification.
  • static byte NON_SPACING_MARK :General category “Mn” in the Unicode specification.
  • static byte OTHER_LETTER :General category “Lo” in the Unicode specification.
  • static byte OTHER_NUMBER :General category “No” in the Unicode specification.
  • static byte OTHER_PUNCTUATION :General category “Po” in the Unicode specification.
  • static byte OTHER_SYMBOL :General category “So” in the Unicode specification.
  • static byte PARAGRAPH_SEPARATOR :General category “Zp” in the Unicode specification.
  • static byte PRIVATE_USE :General category “Co” in the Unicode specification.
  • static int SIZE :The number of bits used to represent a char value in unsigned binary form, constant 16.
  • static byte :SPACE_SEPARATOR :General category “Zs” in the Unicode specification.
  • static byte START_PUNCTUATION :General category “Ps” in the Unicode specification.
  • static byte SURROGATE :General category “Cs” in the Unicode specification.
  • static byte TITLECASE_LETTER :General category “Lt” in the Unicode specification.
  • static Class TYPE :The Class instance representing the primitive type char.
  • static byte UNASSIGNED :General category “Cn” in the Unicode specification.
  • static byte UPPERCASE_LETTER :General category “Lu” in the Unicode specification.

Constructors

  • Character(char value) :Constructs a newly allocated Character object that represents the specified char value.

Methods

  • static int charCount(int codePoint) :Determines the number of char values needed to represent the specified character (Unicode code point).
  • char charValue() :Returns the value of this Character object.\
  • static int codePointAt(char[] a, int index) :Returns the code point at the given index of the char array.
  • static int codePointAt(char[] a, int index, int limit) :Returns the code point at the given index of the char array, where only array elements with index less than limit can be used.
  • static int codePointAt(CharSequence seq, int index) :Returns the code point at the given index of the CharSequence.
  • static int codePointBefore(char[] a, int index) :Returns the code point preceding the given index of the char array.
  • static int codePointBefore(char[] a, int index, int start) :Returns the code point preceding the given index of the char array, where only array elements with index greater than or equal to start can be used.
  • static int codePointBefore(CharSequence seq, int index) :Returns the code point preceding the given index of the CharSequence.
  • static int codePointCount(char[] a, int offset, int count) :Returns the number of Unicode code points in a subarray of the char array argument.
  • static int codePointCount(CharSequence seq, int beginIndex, int endIndex) :Returns the number of Unicode code points in the text range of the specified char sequence.
  • static int compare(char x, char y) :Compares two char values numerically.
  • int compareTo(Character anotherCharacter) :Compares two Character objects numerically.
  • static int digit(char ch, int radix) :Returns the numeric value of the character ch in the specified radix.
  • static int digit(int codePoint, int radix) :Returns the numeric value of the specified character (Unicode code point) in the specified radix.
  • boolean equals(Object obj) :Compares this object against the specified object.
  • static char forDigit(int digit, int radix) :Determines the character representation for a specific digit in the specified radix.
  • static byte getDirectionality(char ch) :Returns the Unicode directionality property for the given character.
  • static byte getDirectionality(int codePoint) :Returns the Unicode directionality property for the given character (Unicode code point).
  • static String getName(int codePoint) :Returns the Unicode name of the specified character codePoint, or null if the code point is unassigned.
  • static int getNumericValue(char ch) :Returns the int value that the specified Unicode character represents.
  • static int getNumericValue(int codePoint) :Returns the int value that the specified character (Unicode code point) represents.
  • static int getType(char ch) :Returns a value indicating a character’s general category.
  • static int getType(int codePoint) :Returns a value indicating a character’s general category.
  • int hashCode() :Returns a hash code for this Character; equal to the result of invoking charValue().
  • static char highSurrogate(int codePoint) :Returns the leading surrogate (a high surrogate code unit) of the surrogate pair representing the specified supplementary character (Unicode code point) in the UTF-16 encoding.
  • static boolean isAlphabetic(int codePoint) :Determines if the specified character (Unicode code point) is an alphabet.
  • static boolean isBmpCodePoint(int codePoint) :Determines whether the specified character (Unicode code point) is in the Basic Multilingual Plane (BMP).
  • static boolean isDefined(char ch) :Determines if a character is defined in Unicode.
  • static boolean isDefined(int codePoint) :Determines if a character (Unicode code point) is defined in Unicode.
  • static boolean isDigit(char ch) :Determines if the specified character is a digit.
  • static boolean isDigit(int codePoint) :Determines if the specified character (Unicode code point) is a digit.
  • static boolean isHighSurrogate(char ch) :Determines if the given char value is a Unicode high-surrogate code unit (also known as leading-surrogate code unit).
  • boolean isIdentifierIgnorable(char ch) :Determines if the specified character should be regarded as an ignorable character in a Java identifier or a Unicode identifier.
  • static boolean isIdentifierIgnorable(int codePoint) :Determines if the specified character (Unicode code point) should be regarded as an ignorable character in a Java identifier or a Unicode identifier.
  • static boolean isIdeographic(int codePoint) :Determines if the specified character (Unicode code point) is a CJKV (Chinese, Japanese, Korean and Vietnamese) ideograph, as defined by the Unicode Standard.
  • static boolean isISOControl(char ch) :Determines if the specified character is an ISO control character.
  • static boolean isISOControl(int codePoint) :Determines if the referenced character (Unicode code point) is an ISO control character.
  • static boolean isJavaIdentifierPart(char ch) :Determines if the specified character may be part of a Java identifier as other than the first character.
  • static boolean isJavaIdentifierPart(int codePoint) :Determines if the character (Unicode code point) may be part of a Java identifier as other than the first character.
  • static boolean isJavaIdentifierStart(char ch) :Determines if the specified character is permissible as the first character in a Java identifier.
  • static boolean isJavaIdentifierStart(int codePoint) :Determines if the character (Unicode code point) is permissible as the first character in a Java identifier.
  • static boolean isJavaLetter(char ch) :Deprecated. Replaced by isJavaIdentifierStart(char).
  • static boolean isJavaLetterOrDigit(char ch) :Deprecated. Replaced by isJavaIdentifierPart(char).
  • static boolean isLetter(char ch) :Determines if the specified character is a letter.
  • static boolean isLetter(int codePoint) :Determines if the specified character (Unicode code point) is a letter.
  • static boolean isLetterOrDigit(char ch) :Determines if the specified character is a letter or digit.
  • static boolean isLetterOrDigit(int codePoint) :Determines if the specified character (Unicode code point) is a letter or digit.
  • static boolean isLowerCase(char ch) :Determines if the specified character is a lowercase character.
  • static boolean isLowerCase(int codePoint) :Determines if the specified character (Unicode code point) is a lowercase character.
  • static boolean isLowSurrogate(char ch) :Determines if the given char value is a Unicode low-surrogate code unit (also known as trailing-surrogate code unit).
  • static boolean isMirrored(char ch) :Determines whether the character is mirrored according to the Unicode specification.
  • static boolean isMirrored(int codePoint) :Determines whether the specified character (Unicode code point) is mirrored according to the Unicode specification.
  • static boolean isSpace(char ch) :Deprecated. Replaced by isWhitespace(char).\
  • static boolean isSpaceChar(char ch) :Determines if the specified character is a Unicode space character.
  • static boolean isSpaceChar(int codePoint) :Determines if the specified character (Unicode code point) is a Unicode space character.
  • static boolean isSupplementaryCodePoint(int codePoint) :Determines whether the specified character (Unicode code point) is in the supplementary character range.
  • static boolean isSurrogate(char ch) :Determines if the given char value is a Unicode surrogate code unit.
  • static boolean isSurrogatePair(char high, char low) :Determines whether the specified pair of char values is a valid Unicode surrogate pair.
  • static boolean isTitleCase(char ch) :Determines if the specified character is a titlecase character.\
  • static boolean :isTitleCase(int codePoint) :Determines if the specified character (Unicode code point) is a titlecase character.
  • static boolean isUnicodeIdentifierPart(char ch) :Determines if the specified character may be part of a Unicode identifier as other than the first character.
  • static boolean isUnicodeIdentifierPart(int codePoint) :Determines if the specified character (Unicode code point) may be part of a Unicode identifier as other than the first character.
  • static boolean isUnicodeIdentifierStart(char ch) :Determines if the specified character is permissible as the first character in a Unicode identifier.
  • static boolean isUnicodeIdentifierStart(int codePoint) :Determines if the specified character (Unicode code point) is permissible as the first character in a Unicode identifier.
  • boolean isUpperCase(char ch) :Determines if the specified character is an uppercase character.
  • static boolean isUpperCase(int codePoint) :Determines if the specified character (Unicode code point) is an uppercase character.
  • static boolean isValidCodePoint(int codePoint) :Determines whether the specified code point is a valid Unicode code point value.
  • static boolean isWhitespace(char ch) :Determines if the specified character is white space according to Java.
  • static boolean isWhitespace(int codePoint) :Determines if the specified character (Unicode code point) is white space according to Java.
  • static char lowSurrogate(int codePoint) :Returns the trailing surrogate (a low surrogate code unit) of the surrogate pair representing the specified supplementary character (Unicode code point) in the UTF-16 encoding.
  • static int offsetByCodePoints(char[] a, int start, int count, int index, int codePointOffset) :Returns the index within the given char subarray that is offset from the given index by codePointOffset code points.
  • static int offsetByCodePoints(CharSequence seq, int index, int codePointOffset) :Returns the index within the given char sequence that is offset from the given index by codePointOffset code points.
  • static char reverseBytes(char ch) :Returns the value obtained by reversing the order of the bytes in the specified char value.
  • static char[] toChars(int codePoint) :Converts the specified character (Unicode code point) to its UTF-16 representation stored in a char array.
  • static int toChars(int codePoint, char[] dst, int dstIndex) :Converts the specified character (Unicode code point) to its UTF-16 representation.
  • static int toCodePoint(char high, char low) :Converts the specified surrogate pair to its supplementary code point value.
  • static char toLowerCase(char ch) :Converts the character argument to lowercase using case mapping information from the UnicodeData file.
  • static int toLowerCase(int codePoint) :Converts the character (Unicode code point) argument to lowercase using case mapping information from the UnicodeData file.
  • String toString() :Returns a String object representing this Character’s value.
  • static String toString(char c) :Returns a String object representing the specified char.
  • static char toTitleCase(char ch) :Converts the character argument to titlecase using case mapping information from the UnicodeData file.
  • static int toTitleCase(int codePoint) :Converts the character (Unicode code point) argument to titlecase using case mapping information from the UnicodeData file.
  • static char toUpperCase(char ch) :Converts the character argument to uppercase using case mapping information from the UnicodeData file.
  • static int toUpperCase(int codePoint) :Converts the character (Unicode code point) argument to uppercase using case mapping information from the UnicodeData file.
  • static Character valueOf(char c) :Returns a Character instance representing the specified char value.

References