public final classCharacterextendsObjectimplementsSerializable,Comparable<Character>
Character class wraps a value of the primitive typechar in an object. An object of classCharacter contains a single field whose type ischar.In addition, this class provides a large number of static methods for determining a character's category (lowercase letter, digit, etc.) and for converting characters from uppercase to lowercase and vice versa.
The fields and methods of classCharacter are defined in terms of character information from the Unicode Standard, specifically theUnicodeData file that is part of the Unicode Character Database. This file specifies properties including name and category for every assigned Unicode code point or character range. The file is available from the Unicode Consortium athttp://www.unicode.org.
The Java SE 8 Platform uses character information from version 6.2 of the Unicode Standard, with three extensions. First, in recognition of the fact that new currencies appear frequently, the Java SE 8 Platform allows an implementation of classCharacter to use the Currency Symbols block from version 10.0 of the Unicode Standard. Second, the Java SE 8 Platform allows an implementation of classCharacter to use the code points in the range ofU+9FCD toU+9FEF from version 11.0 of the Unicode Standard and in theCJK Unified Ideographs Extension E block from version 8.0 of the Unicode Standard, in order for the class to allow the "Implementation Level 2" of the Chinese GB18030-2022 standard. Third, the Java SE 8 Platform allows an implementation of classCharacter to use the Japanese Era code point,U+32FF, from the Unicode Standard version 12.1. Consequently, the behavior of fields and methods of classCharacter may vary across implementations of the Java SE 8 Platform when processing the aforementioned code points ( outside of version 6.2 ), except for the following methods that define Java identifiers:isJavaIdentifierStart(int),isJavaIdentifierStart(char),isJavaIdentifierPart(int), andisJavaIdentifierPart(char). Code points in Java identifiers must be drawn from version 6.2 of the Unicode Standard.
Thechar data type (and therefore the value that aCharacter object encapsulates) are based on the original Unicode specification, which defined characters as fixed-width 16-bit entities. The Unicode Standard has since been changed to allow for characters whose representation requires more than 16 bits. The range of legalcode points is now U+0000 to U+10FFFF, known asUnicode scalar value. (Refer to the definition of the U+n notation in the Unicode Standard.)
The set of characters from U+0000 to U+FFFF is sometimes referred to as theBasic Multilingual Plane (BMP).Characters whose code points are greater than U+FFFF are calledsupplementary characters. The Java platform uses the UTF-16 representation inchar arrays and in theString andStringBuffer classes. In this representation, supplementary characters are represented as a pair ofchar values, the first from thehigh-surrogates range, (\uD800-\uDBFF), the second from thelow-surrogates range (\uDC00-\uDFFF).
Achar value, therefore, represents Basic Multilingual Plane (BMP) code points, including the surrogate code points, or code units of the UTF-16 encoding. Anint value represents all Unicode code points, including supplementary code points. The lower (least significant) 21 bits ofint are used to represent Unicode code points and the upper (most significant) 11 bits must be zero. Unless otherwise specified, the behavior with respect to supplementary characters and surrogatechar values is as follows:
char value cannot support supplementary characters. They treatchar values from the surrogate ranges as undefined characters. For example,Character.isLetter('\uD840') returnsfalse, even though this specific value if followed by any low-surrogate value in a string would represent a letter.int value support all Unicode characters, including supplementary characters. For example,Character.isLetter(0x2F81A) returnstrue because the code point value represents a letter (a CJK ideograph).In the Java SE API documentation,Unicode code point is used for character values in the range between U+0000 and U+10FFFF, andUnicode code unit is used for 16-bitchar values that are code units of theUTF-16 encoding. For more information on Unicode terminology, refer to theUnicode Glossary.
| Modifier and Type | Class | Description |
|---|---|---|
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 character blocks in the Unicode specification. |
static class | Character.UnicodeScript | A family of character subsets representing the character scripts defined in theUnicode Standard Annex #24: Script Names. |
| Modifier and Type | Field | Description |
|---|---|---|
static int | BYTES | The number of bytes used to represent a char value in unsigned binary form. |
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 achar 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. |
staticClass<Character> | TYPE | The Class instance representing the primitive typechar. |
static byte | UNASSIGNED | General category "Cn" in the Unicode specification. |
static byte | UPPERCASE_LETTER | General category "Lu" in the Unicode specification. |
| Constructor | Description |
|---|---|
Character(char value) | Constructs a newly allocated Character object that represents the specifiedchar value. |
| Modifier and Type | Method | Description |
|---|---|---|
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 withindex less thanlimit 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 withindex greater than or equal tostart 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). |
staticString | getName(int codePoint) | Returns the Unicode name of the specified character codePoint, or null if the code point isunassigned. |
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 invokingcharValue(). |
static int | hashCode(char value) | Returns a hash code for a char value; compatible withCharacter.hashCode(). |
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 theBasic 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 asleading-surrogate code unit). |
static 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 astrailing-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 thesupplementary character range. |
static boolean | isSurrogate(char ch) | Determines if the given char value is a Unicodesurrogate 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. |
static 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 givenindex bycodePointOffset 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 bycodePointOffset code points. |
static char | reverseBytes(char ch) | Returns the value obtained by reversing the order of the bytes in the specifiedchar 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 thisCharacter's value. |
staticString | toString(char c) | Returns a String object representing the specifiedchar. |
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. |
staticCharacter | valueOf(char c) | Returns aCharacter instance representing the specifiedchar value. |
public static final int MIN_RADIX
digit method, theforDigit method, and thetoString method of classInteger.public static final int MAX_RADIX
digit method, theforDigit method, and thetoString method of classInteger.public static final char MIN_VALUE
char,'\u0000'.public static final char MAX_VALUE
char,'\uFFFF'.public static final Class<Character> TYPE
Class instance representing the primitive typechar.public static final byte UNASSIGNED
public static final byte UPPERCASE_LETTER
public static final byte LOWERCASE_LETTER
public static final byte TITLECASE_LETTER
public static final byte MODIFIER_LETTER
public static final byte OTHER_LETTER
public static final byte NON_SPACING_MARK
public static final byte ENCLOSING_MARK
public static final byte COMBINING_SPACING_MARK
public static final byte DECIMAL_DIGIT_NUMBER
public static final byte LETTER_NUMBER
public static final byte OTHER_NUMBER
public static final byte SPACE_SEPARATOR
public static final byte LINE_SEPARATOR
public static final byte PARAGRAPH_SEPARATOR
public static final byte CONTROL
public static final byte FORMAT
public static final byte PRIVATE_USE
public static final byte SURROGATE
public static final byte DASH_PUNCTUATION
public static final byte START_PUNCTUATION
public static final byte END_PUNCTUATION
public static final byte CONNECTOR_PUNCTUATION
public static final byte OTHER_PUNCTUATION
public static final byte MATH_SYMBOL
public static final byte CURRENCY_SYMBOL
public static final byte MODIFIER_SYMBOL
public static final byte OTHER_SYMBOL
public static final byte INITIAL_QUOTE_PUNCTUATION
public static final byte FINAL_QUOTE_PUNCTUATION
public static final byte DIRECTIONALITY_UNDEFINED
char values have undefined directionality in the Unicode specification.public static final byte DIRECTIONALITY_LEFT_TO_RIGHT
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR
public static final byte DIRECTIONALITY_ARABIC_NUMBER
public static final byte DIRECTIONALITY_COMMON_NUMBER_SEPARATOR
public static final byte DIRECTIONALITY_NONSPACING_MARK
public static final byte DIRECTIONALITY_BOUNDARY_NEUTRAL
public static final byte DIRECTIONALITY_PARAGRAPH_SEPARATOR
public static final byte DIRECTIONALITY_SEGMENT_SEPARATOR
public static final byte DIRECTIONALITY_WHITESPACE
public static final byte DIRECTIONALITY_OTHER_NEUTRALS
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE
public static final byte DIRECTIONALITY_POP_DIRECTIONAL_FORMAT
public static final char MIN_HIGH_SURROGATE
'\uD800'. A high-surrogate is also known as aleading-surrogate.public static final char MAX_HIGH_SURROGATE
'\uDBFF'. A high-surrogate is also known as aleading-surrogate.public static final char MIN_LOW_SURROGATE
'\uDC00'. A low-surrogate is also known as atrailing-surrogate.public static final char MAX_LOW_SURROGATE
'\uDFFF'. A low-surrogate is also known as atrailing-surrogate.public static final char MIN_SURROGATE
'\uD800'.public static final char MAX_SURROGATE
'\uDFFF'.public static final int MIN_SUPPLEMENTARY_CODE_POINT
U+10000.public static final int MIN_CODE_POINT
U+0000.public static final int MAX_CODE_POINT
U+10FFFF.public static final int SIZE
16.public static final int BYTES
char value in unsigned binary form.public Character(char value)
Character object that represents the specifiedchar value.value - the value to be represented by theCharacter object.public static Character valueOf(char c)
Character(char), as this method is likely to yield significantly better space and time performance by caching frequently requested values. This method will always cache values in the range'\u0000' to'\u007F', inclusive, and may cache other values outside of this range.c - a char value.public char charValue()
Character object.char value represented by this object.public int hashCode()
Character; equal to the result of invokingcharValue().hashCode in class ObjectCharacterObject.equals(java.lang.Object),System.identityHashCode(java.lang.Object)public static int hashCode(char value)
char value; compatible withCharacter.hashCode().value - Thechar for which to return a hash code.char value.public boolean equals(Object obj)
true if and only if the argument is notnull and is aCharacter object that represents the samechar value as this object.equals in class Objectobj - the object to compare with.true if the objects are the same;false otherwise.Object.hashCode(),HashMappublic String toString()
String object representing thisCharacter's value. The result is a string of length 1 whose sole component is the primitivechar value represented by thisCharacter object.public static String toString(char c)
String object representing the specifiedchar. The result is a string of length 1 consisting solely of the specifiedchar.c - thechar to be convertedcharpublic static boolean isValidCodePoint(int codePoint)
codePoint - the Unicode code point to be testedtrue if the specified code point value is betweenMIN_CODE_POINT andMAX_CODE_POINT inclusive;false otherwise.public static boolean isBmpCodePoint(int codePoint)
char.public static boolean isSupplementaryCodePoint(int codePoint)
codePoint - the character (Unicode code point) to be testedtrue if the specified code point is betweenMIN_SUPPLEMENTARY_CODE_POINT andMAX_CODE_POINT inclusive;false otherwise.public static boolean isHighSurrogate(char ch)
char value is a Unicode high-surrogate code unit (also known asleading-surrogate code unit).Such values do not represent characters by themselves, but are used in the representation ofsupplementary characters in the UTF-16 encoding.
ch - thechar value to be tested.true if thechar value is betweenMIN_HIGH_SURROGATE andMAX_HIGH_SURROGATE inclusive;false otherwise.isLowSurrogate(char),Character.UnicodeBlock.of(int)public static boolean isLowSurrogate(char ch)
char value is a Unicode low-surrogate code unit (also known astrailing-surrogate code unit).Such values do not represent characters by themselves, but are used in the representation ofsupplementary characters in the UTF-16 encoding.
ch - thechar value to be tested.true if thechar value is betweenMIN_LOW_SURROGATE andMAX_LOW_SURROGATE inclusive;false otherwise.isHighSurrogate(char)public static boolean isSurrogate(char ch)
char value is a Unicodesurrogate code unit.Such values do not represent characters by themselves, but are used in the representation ofsupplementary characters in the UTF-16 encoding.
A char value is a surrogate code unit if and only if it is either alow-surrogate code unit or ahigh-surrogate code unit.
ch - thechar value to be tested.true if thechar value is betweenMIN_SURROGATE andMAX_SURROGATE inclusive;false otherwise.public static boolean isSurrogatePair(char high, char low)
char values is a valid Unicode surrogate pair.This method is equivalent to the expression:
isHighSurrogate(high) && isLowSurrogate(low)
high - the high-surrogate code value to be testedlow - the low-surrogate code value to be testedtrue if the specified high and low-surrogate code values represent a valid surrogate pair;false otherwise.public static int charCount(int codePoint)
char values needed to represent the specified character (Unicode code point). If the specified character is equal to or greater than 0x10000, then the method returns 2. Otherwise, the method returns 1.This method doesn't validate the specified character to be a valid Unicode code point. The caller must validate the character value usingisValidCodePoint if necessary.
codePoint - the character (Unicode code point) to be tested.isSupplementaryCodePoint(int)public static int toCodePoint(char high, char low)
isSurrogatePair if necessary.high - the high-surrogate code unitlow - the low-surrogate code unitpublic static int codePointAt(CharSequence seq, int index)
CharSequence. If thechar value at the given index in theCharSequence is in the high-surrogate range, the following index is less than the length of theCharSequence, and thechar value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thechar value at the given index is returned.seq - a sequence ofchar values (Unicode code units)index - the index to thechar values (Unicode code units) inseq to be convertedNullPointerException - ifseq is null.IndexOutOfBoundsException - if the valueindex is negative or not less thanseq.length().public static int codePointAt(char[] a, int index)
char array. If thechar value at the given index in thechar array is in the high-surrogate range, the following index is less than the length of thechar array, and thechar value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thechar value at the given index is returned.a - thechar arrayindex - the index to thechar values (Unicode code units) in thechar array to be convertedNullPointerException - ifa is null.IndexOutOfBoundsException - if the valueindex is negative or not less than the length of thechar array.public static int codePointAt(char[] a, int index, int limit)
char array, where only array elements withindex less thanlimit can be used. If thechar value at the given index in thechar array is in the high-surrogate range, the following index is less than thelimit, and thechar value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thechar value at the given index is returned.a - thechar arrayindex - the index to thechar values (Unicode code units) in thechar array to be convertedlimit - the index after the last array element that can be used in thechar arrayNullPointerException - ifa is null.IndexOutOfBoundsException - if theindex argument is negative or not less than thelimit argument, or if thelimit argument is negative or greater than the length of thechar array.public static int codePointBefore(CharSequence seq, int index)
CharSequence. If thechar value at(index - 1) in theCharSequence is in the low-surrogate range,(index - 2) is not negative, and thechar value at(index - 2) in theCharSequence is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thechar value at(index - 1) is returned.seq - theCharSequence instanceindex - the index following the code point that should be returnedNullPointerException - ifseq is null.IndexOutOfBoundsException - if theindex argument is less than 1 or greater thanseq.length().public static int codePointBefore(char[] a, int index)
char array. If thechar value at(index - 1) in thechar array is in the low-surrogate range,(index - 2) is not negative, and thechar value at(index - 2) in thechar array is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thechar value at(index - 1) is returned.a - thechar arrayindex - the index following the code point that should be returnedNullPointerException - ifa is null.IndexOutOfBoundsException - if theindex argument is less than 1 or greater than the length of thechar arraypublic static int codePointBefore(char[] a, int index, int start)
char array, where only array elements withindex greater than or equal tostart can be used. If thechar value at(index - 1) in thechar array is in the low-surrogate range,(index - 2) is not less thanstart, and thechar value at(index - 2) in thechar array is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thechar value at(index - 1) is returned.a - thechar arrayindex - the index following the code point that should be returnedstart - the index of the first array element in thechar arrayNullPointerException - ifa is null.IndexOutOfBoundsException - if theindex argument is not greater than thestart argument or is greater than the length of thechar array, or if thestart argument is negative or not less than the length of thechar array.public static char highSurrogate(int codePoint)
char is returned.IfisSupplementaryCodePoint(x) istrue, thenisHighSurrogate(highSurrogate(x)) andtoCodePoint(highSurrogate(x),lowSurrogate(x)) == x are also alwaystrue.
codePoint - a supplementary character (Unicode code point)public static char lowSurrogate(int codePoint)
char is returned.IfisSupplementaryCodePoint(x) istrue, thenisLowSurrogate(lowSurrogate(x)) andtoCodePoint(highSurrogate(x), lowSurrogate(x)) == x are also alwaystrue.
codePoint - a supplementary character (Unicode code point)public static int toChars(int codePoint, char[] dst, int dstIndex)
dst[dstIndex], and 1 is returned. If the specified code point is a supplementary character, its surrogate values are stored indst[dstIndex] (high-surrogate) anddst[dstIndex+1] (low-surrogate), and 2 is returned.codePoint - the character (Unicode code point) to be converted.dst - an array ofchar in which thecodePoint's UTF-16 value is stored.dstIndex - the start index into thedst array where the converted value is stored.IllegalArgumentException - if the specifiedcodePoint is not a valid Unicode code point.NullPointerException - if the specifieddst is null.IndexOutOfBoundsException - ifdstIndex is negative or not less thandst.length, or ifdst atdstIndex doesn't have enough array element(s) to store the resultingchar value(s). (IfdstIndex is equal todst.length-1 and the specifiedcodePoint is a supplementary character, the high-surrogate value is not stored indst[dstIndex].)public static char[] toChars(int codePoint)
char array. If the specified code point is a BMP (Basic Multilingual Plane or Plane 0) value, the resultingchar array has the same value ascodePoint. If the specified code point is a supplementary code point, the resultingchar array has the corresponding surrogate pair.codePoint - a Unicode code pointchar array havingcodePoint's UTF-16 representation.IllegalArgumentException - if the specifiedcodePoint is not a valid Unicode code point.public static int codePointCount(CharSequence seq, int beginIndex, int endIndex)
beginIndex and extends to thechar at indexendIndex - 1. Thus the length (inchars) of the text range isendIndex-beginIndex. Unpaired surrogates within the text range count as one code point each.seq - the char sequencebeginIndex - the index to the firstchar of the text range.endIndex - the index after the lastchar of the text range.NullPointerException - ifseq is null.IndexOutOfBoundsException - if thebeginIndex is negative, orendIndex is larger than the length of the given sequence, orbeginIndex is larger thanendIndex.public static int codePointCount(char[] a, int offset, int count)
char array argument. Theoffset argument is the index of the firstchar of the subarray and thecount argument specifies the length of the subarray inchars. Unpaired surrogates within the subarray count as one code point each.a - thechar arrayoffset - the index of the firstchar in the givenchar arraycount - the length of the subarray incharsNullPointerException - ifa is null.IndexOutOfBoundsException - ifoffset orcount is negative, or ifoffset + count is larger than the length of the given array.public static int offsetByCodePoints(CharSequence seq, int index, int codePointOffset)
index bycodePointOffset code points. Unpaired surrogates within the text range given byindex andcodePointOffset count as one code point each.seq - the char sequenceindex - the index to be offsetcodePointOffset - the offset in code pointsNullPointerException - ifseq is null.IndexOutOfBoundsException - ifindex is negative or larger then the length of the char sequence, or ifcodePointOffset is positive and the subsequence starting withindex has fewer thancodePointOffset code points, or ifcodePointOffset is negative and the subsequence beforeindex has fewer than the absolute value ofcodePointOffset code points.public static int offsetByCodePoints(char[] a, int start, int count, int index, int codePointOffset)
char subarray that is offset from the givenindex bycodePointOffset code points. Thestart andcount arguments specify a subarray of thechar array. Unpaired surrogates within the text range given byindex andcodePointOffset count as one code point each.a - thechar arraystart - the index of the firstchar of the subarraycount - the length of the subarray incharsindex - the index to be offsetcodePointOffset - the offset in code pointsNullPointerException - ifa is null.IndexOutOfBoundsException - ifstart orcount is negative, or ifstart + count is larger than the length of the given array, or ifindex is less thanstart or larger thenstart + count, or ifcodePointOffset is positive and the text range starting withindex and ending withstart + count - 1 has fewer thancodePointOffset code points, or ifcodePointOffset is negative and the text range starting withstart and ending withindex - 1 has fewer than the absolute value ofcodePointOffset code points.public static boolean isLowerCase(char ch)
A character is lowercase if its general category type, provided byCharacter.getType(ch), isLOWERCASE_LETTER, or it has contributory property Other_Lowercase as defined by the Unicode Standard.
The following are examples of lowercase characters:
a b c d e f g h i j k l m n o p q r s t u v w x y z '\u00DF' '\u00E0' '\u00E1' '\u00E2' '\u00E3' '\u00E4' '\u00E5' '\u00E6' '\u00E7' '\u00E8' '\u00E9' '\u00EA' '\u00EB' '\u00EC' '\u00ED' '\u00EE' '\u00EF' '\u00F0' '\u00F1' '\u00F2' '\u00F3' '\u00F4' '\u00F5' '\u00F6' '\u00F8' '\u00F9' '\u00FA' '\u00FB' '\u00FC' '\u00FD' '\u00FE' '\u00FF'
Many other Unicode characters are lowercase too.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisLowerCase(int) method.
ch - the character to be tested.true if the character is lowercase;false otherwise.isLowerCase(char),isTitleCase(char),toLowerCase(char),getType(char)public static boolean isLowerCase(int codePoint)
A character is lowercase if its general category type, provided bygetType(codePoint), isLOWERCASE_LETTER, or it has contributory property Other_Lowercase as defined by the Unicode Standard.
The following are examples of lowercase characters:
a b c d e f g h i j k l m n o p q r s t u v w x y z '\u00DF' '\u00E0' '\u00E1' '\u00E2' '\u00E3' '\u00E4' '\u00E5' '\u00E6' '\u00E7' '\u00E8' '\u00E9' '\u00EA' '\u00EB' '\u00EC' '\u00ED' '\u00EE' '\u00EF' '\u00F0' '\u00F1' '\u00F2' '\u00F3' '\u00F4' '\u00F5' '\u00F6' '\u00F8' '\u00F9' '\u00FA' '\u00FB' '\u00FC' '\u00FD' '\u00FE' '\u00FF'
Many other Unicode characters are lowercase too.
codePoint - the character (Unicode code point) to be tested.true if the character is lowercase;false otherwise.isLowerCase(int),isTitleCase(int),toLowerCase(int),getType(int)public static boolean isUpperCase(char ch)
A character is uppercase if its general category type, provided byCharacter.getType(ch), isUPPERCASE_LETTER. or it has contributory property Other_Uppercase as defined by the Unicode Standard.
The following are examples of uppercase characters:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z '\u00C0' '\u00C1' '\u00C2' '\u00C3' '\u00C4' '\u00C5' '\u00C6' '\u00C7' '\u00C8' '\u00C9' '\u00CA' '\u00CB' '\u00CC' '\u00CD' '\u00CE' '\u00CF' '\u00D0' '\u00D1' '\u00D2' '\u00D3' '\u00D4' '\u00D5' '\u00D6' '\u00D8' '\u00D9' '\u00DA' '\u00DB' '\u00DC' '\u00DD' '\u00DE'
Many other Unicode characters are uppercase too.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisUpperCase(int) method.
ch - the character to be tested.true if the character is uppercase;false otherwise.isLowerCase(char),isTitleCase(char),toUpperCase(char),getType(char)public static boolean isUpperCase(int codePoint)
A character is uppercase if its general category type, provided bygetType(codePoint), isUPPERCASE_LETTER, or it has contributory property Other_Uppercase as defined by the Unicode Standard.
The following are examples of uppercase characters:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z '\u00C0' '\u00C1' '\u00C2' '\u00C3' '\u00C4' '\u00C5' '\u00C6' '\u00C7' '\u00C8' '\u00C9' '\u00CA' '\u00CB' '\u00CC' '\u00CD' '\u00CE' '\u00CF' '\u00D0' '\u00D1' '\u00D2' '\u00D3' '\u00D4' '\u00D5' '\u00D6' '\u00D8' '\u00D9' '\u00DA' '\u00DB' '\u00DC' '\u00DD' '\u00DE'
Many other Unicode characters are uppercase too.
codePoint - the character (Unicode code point) to be tested.true if the character is uppercase;false otherwise.isLowerCase(int),isTitleCase(int),toUpperCase(int),getType(int)public static boolean isTitleCase(char ch)
A character is a titlecase character if its general category type, provided byCharacter.getType(ch), isTITLECASE_LETTER.
Some characters look like pairs of Latin letters. For example, there is an uppercase letter that looks like "LJ" and has a corresponding lowercase letter that looks like "lj". A third form, which looks like "Lj", is the appropriate form to use when rendering a word in lowercase with initial capitals, as for a book title.
These are some of the Unicode characters for which this method returnstrue:
LATIN CAPITAL LETTER D WITH SMALL LETTER Z WITH CARONLATIN CAPITAL LETTER L WITH SMALL LETTER JLATIN CAPITAL LETTER N WITH SMALL LETTER JLATIN CAPITAL LETTER D WITH SMALL LETTER ZMany other Unicode characters are titlecase too.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisTitleCase(int) method.
ch - the character to be tested.true if the character is titlecase;false otherwise.isLowerCase(char),isUpperCase(char),toTitleCase(char),getType(char)public static boolean isTitleCase(int codePoint)
A character is a titlecase character if its general category type, provided bygetType(codePoint), isTITLECASE_LETTER.
Some characters look like pairs of Latin letters. For example, there is an uppercase letter that looks like "LJ" and has a corresponding lowercase letter that looks like "lj". A third form, which looks like "Lj", is the appropriate form to use when rendering a word in lowercase with initial capitals, as for a book title.
These are some of the Unicode characters for which this method returnstrue:
LATIN CAPITAL LETTER D WITH SMALL LETTER Z WITH CARONLATIN CAPITAL LETTER L WITH SMALL LETTER JLATIN CAPITAL LETTER N WITH SMALL LETTER JLATIN CAPITAL LETTER D WITH SMALL LETTER ZMany other Unicode characters are titlecase too.
codePoint - the character (Unicode code point) to be tested.true if the character is titlecase;false otherwise.isLowerCase(int),isUpperCase(int),toTitleCase(int),getType(int)public static boolean isDigit(char ch)
A character is a digit if its general category type, provided byCharacter.getType(ch), isDECIMAL_DIGIT_NUMBER.
Some Unicode character ranges that contain digits:
'\u0030' through'\u0039', ISO-LATIN-1 digits ('0' through'9')'\u0660' through'\u0669', Arabic-Indic digits'\u06F0' through'\u06F9', Extended Arabic-Indic digits'\u0966' through'\u096F', Devanagari digits'\uFF10' through'\uFF19', Fullwidth digitsNote: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisDigit(int) method.
ch - the character to be tested.true if the character is a digit;false otherwise.digit(char, int),forDigit(int, int),getType(char)public static boolean isDigit(int codePoint)
A character is a digit if its general category type, provided bygetType(codePoint), isDECIMAL_DIGIT_NUMBER.
Some Unicode character ranges that contain digits:
'\u0030' through'\u0039', ISO-LATIN-1 digits ('0' through'9')'\u0660' through'\u0669', Arabic-Indic digits'\u06F0' through'\u06F9', Extended Arabic-Indic digits'\u0966' through'\u096F', Devanagari digits'\uFF10' through'\uFF19', Fullwidth digitscodePoint - the character (Unicode code point) to be tested.true if the character is a digit;false otherwise.forDigit(int, int),getType(int)public static boolean isDefined(char ch)
A character is defined if at least one of the following is true:
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisDefined(int) method.
ch - the character to be testedtrue if the character has a defined meaning in Unicode;false otherwise.isDigit(char),isLetter(char),isLetterOrDigit(char),isLowerCase(char),isTitleCase(char),isUpperCase(char)public static boolean isDefined(int codePoint)
A character is defined if at least one of the following is true:
codePoint - the character (Unicode code point) to be tested.true if the character has a defined meaning in Unicode;false otherwise.isDigit(int),isLetter(int),isLetterOrDigit(int),isLowerCase(int),isTitleCase(int),isUpperCase(int)public static boolean isLetter(char ch)
A character is considered to be a letter if its general category type, provided byCharacter.getType(ch), is any of the following:
UPPERCASE_LETTERLOWERCASE_LETTERTITLECASE_LETTERMODIFIER_LETTEROTHER_LETTERNote: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisLetter(int) method.
ch - the character to be tested.true if the character is a letter;false otherwise.isDigit(char),isJavaIdentifierStart(char),isJavaLetter(char),isJavaLetterOrDigit(char),isLetterOrDigit(char),isLowerCase(char),isTitleCase(char),isUnicodeIdentifierStart(char),isUpperCase(char)public static boolean isLetter(int codePoint)
A character is considered to be a letter if its general category type, provided bygetType(codePoint), is any of the following:
UPPERCASE_LETTERLOWERCASE_LETTERTITLECASE_LETTERMODIFIER_LETTEROTHER_LETTERcodePoint - the character (Unicode code point) to be tested.true if the character is a letter;false otherwise.isDigit(int),isJavaIdentifierStart(int),isLetterOrDigit(int),isLowerCase(int),isTitleCase(int),isUnicodeIdentifierStart(int),isUpperCase(int)public static boolean isLetterOrDigit(char ch)
A character is considered to be a letter or digit if eitherCharacter.isLetter(char ch) orCharacter.isDigit(char ch) returnstrue for the character.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisLetterOrDigit(int) method.
ch - the character to be tested.true if the character is a letter or digit;false otherwise.isDigit(char),isJavaIdentifierPart(char),isJavaLetter(char),isJavaLetterOrDigit(char),isLetter(char),isUnicodeIdentifierPart(char)public static boolean isLetterOrDigit(int codePoint)
A character is considered to be a letter or digit if eitherisLetter(codePoint) orisDigit(codePoint) returnstrue for the character.
codePoint - the character (Unicode code point) to be tested.true if the character is a letter or digit;false otherwise.isDigit(int),isJavaIdentifierPart(int),isLetter(int),isUnicodeIdentifierPart(int)@Deprecatedpublic static boolean isJavaLetter(char ch)
A character may start a Java identifier if and only if one of the following conditions is true:
isLetter(ch) returnstruegetType(ch) returnsLETTER_NUMBERch is a currency symbol (such as'$')ch is a connecting punctuation character (such as'_').ch - the character to be tested.true if the character may start a Java identifier;false otherwise.isJavaLetterOrDigit(char),isJavaIdentifierStart(char),isJavaIdentifierPart(char),isLetter(char),isLetterOrDigit(char),isUnicodeIdentifierStart(char)@Deprecatedpublic static boolean isJavaLetterOrDigit(char ch)
A character may be part of a Java identifier if and only if any of the following conditions are true:
'$')'_')isIdentifierIgnorable returnstrue for the character.ch - the character to be tested.true if the character may be part of a Java identifier;false otherwise.isJavaLetter(char),isJavaIdentifierStart(char),isJavaIdentifierPart(char),isLetter(char),isLetterOrDigit(char),isUnicodeIdentifierPart(char),isIdentifierIgnorable(char)public static boolean isAlphabetic(int codePoint)
A character is considered to be alphabetic if its general category type, provided bygetType(codePoint), is any of the following:
UPPERCASE_LETTERLOWERCASE_LETTERTITLECASE_LETTERMODIFIER_LETTEROTHER_LETTERLETTER_NUMBERcodePoint - the character (Unicode code point) to be tested.true if the character is a Unicode alphabet character,false otherwise.public static boolean isIdeographic(int codePoint)
codePoint - the character (Unicode code point) to be tested.true if the character is a Unicode ideograph character,false otherwise.public static boolean isJavaIdentifierStart(char ch)
A character may start a Java identifier if and only if one of the following conditions is true:
isLetter(ch) returnstruegetType(ch) returnsLETTER_NUMBERch is a currency symbol (such as'$')ch is a connecting punctuation character (such as'_').Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisJavaIdentifierStart(int) method.
ch - the character to be tested.true if the character may start a Java identifier;false otherwise.isJavaIdentifierPart(char),isLetter(char),isUnicodeIdentifierStart(char),SourceVersion.isIdentifier(CharSequence)public static boolean isJavaIdentifierStart(int codePoint)
A character may start a Java identifier if and only if one of the following conditions is true:
isLetter(codePoint) returnstruegetType(codePoint) returnsLETTER_NUMBER'$')'_').codePoint - the character (Unicode code point) to be tested.true if the character may start a Java identifier;false otherwise.isJavaIdentifierPart(int),isLetter(int),isUnicodeIdentifierStart(int),SourceVersion.isIdentifier(CharSequence)public static boolean isJavaIdentifierPart(char ch)
A character may be part of a Java identifier if any of the following conditions are true:
'$')'_')isIdentifierIgnorable returnstrue for the characterNote: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisJavaIdentifierPart(int) method.
ch - the character to be tested.true if the character may be part of a Java identifier;false otherwise.isIdentifierIgnorable(char),isJavaIdentifierStart(char),isLetterOrDigit(char),isUnicodeIdentifierPart(char),SourceVersion.isIdentifier(CharSequence)public static boolean isJavaIdentifierPart(int codePoint)
A character may be part of a Java identifier if any of the following conditions are true:
'$')'_')isIdentifierIgnorable(codePoint) returnstrue for the code pointcodePoint - the character (Unicode code point) to be tested.true if the character may be part of a Java identifier;false otherwise.isIdentifierIgnorable(int),isJavaIdentifierStart(int),isLetterOrDigit(int),isUnicodeIdentifierPart(int),SourceVersion.isIdentifier(CharSequence)public static boolean isUnicodeIdentifierStart(char ch)
A character may start a Unicode identifier if and only if one of the following conditions is true:
isLetter(ch) returnstruegetType(ch) returnsLETTER_NUMBER.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisUnicodeIdentifierStart(int) method.
ch - the character to be tested.true if the character may start a Unicode identifier;false otherwise.isJavaIdentifierStart(char),isLetter(char),isUnicodeIdentifierPart(char)public static boolean isUnicodeIdentifierStart(int codePoint)
A character may start a Unicode identifier if and only if one of the following conditions is true:
isLetter(codePoint) returnstruegetType(codePoint) returnsLETTER_NUMBER.codePoint - the character (Unicode code point) to be tested.true if the character may start a Unicode identifier;false otherwise.isJavaIdentifierStart(int),isLetter(int),isUnicodeIdentifierPart(int)public static boolean isUnicodeIdentifierPart(char ch)
A character may be part of a Unicode identifier if and only if one of the following statements is true:
'_')isIdentifierIgnorable returnstrue for this character.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisUnicodeIdentifierPart(int) method.
ch - the character to be tested.true if the character may be part of a Unicode identifier;false otherwise.isIdentifierIgnorable(char),isJavaIdentifierPart(char),isLetterOrDigit(char),isUnicodeIdentifierStart(char)public static boolean isUnicodeIdentifierPart(int codePoint)
A character may be part of a Unicode identifier if and only if one of the following statements is true:
'_')isIdentifierIgnorable returnstrue for this character.codePoint - the character (Unicode code point) to be tested.true if the character may be part of a Unicode identifier;false otherwise.isIdentifierIgnorable(int),isJavaIdentifierPart(int),isLetterOrDigit(int),isUnicodeIdentifierStart(int)public static boolean isIdentifierIgnorable(char ch)
The following Unicode characters are ignorable in a Java identifier or a Unicode identifier:
'\u0000' through'\u0008''\u000E' through'\u001B''\u007F' through'\u009F'FORMAT general category valueNote: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisIdentifierIgnorable(int) method.
ch - the character to be tested.true if the character is an ignorable control character that may be part of a Java or Unicode identifier;false otherwise.isJavaIdentifierPart(char),isUnicodeIdentifierPart(char)public static boolean isIdentifierIgnorable(int codePoint)
The following Unicode characters are ignorable in a Java identifier or a Unicode identifier:
'\u0000' through'\u0008''\u000E' through'\u001B''\u007F' through'\u009F'FORMAT general category valuecodePoint - the character (Unicode code point) to be tested.true if the character is an ignorable control character that may be part of a Java or Unicode identifier;false otherwise.isJavaIdentifierPart(int),isUnicodeIdentifierPart(int)public static char toLowerCase(char ch)
Note thatCharacter.isLowerCase(Character.toLowerCase(ch)) does not always returntrue for some ranges of characters, particularly those that are symbols or ideographs.
In general,String.toLowerCase() should be used to map characters to lowercase.String case mapping methods have several benefits overCharacter case mapping methods.String case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharacter case mapping methods cannot.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thetoLowerCase(int) method.
ch - the character to be converted.isLowerCase(char),String.toLowerCase()public static int toLowerCase(int codePoint)
Note thatCharacter.isLowerCase(Character.toLowerCase(codePoint)) does not always returntrue for some ranges of characters, particularly those that are symbols or ideographs.
In general,String.toLowerCase() should be used to map characters to lowercase.String case mapping methods have several benefits overCharacter case mapping methods.String case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharacter case mapping methods cannot.
codePoint - the character (Unicode code point) to be converted.isLowerCase(int),String.toLowerCase()public static char toUpperCase(char ch)
Note thatCharacter.isUpperCase(Character.toUpperCase(ch)) does not always returntrue for some ranges of characters, particularly those that are symbols or ideographs.
In general,String.toUpperCase() should be used to map characters to uppercase.String case mapping methods have several benefits overCharacter case mapping methods.String case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharacter case mapping methods cannot.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thetoUpperCase(int) method.
ch - the character to be converted.isUpperCase(char),String.toUpperCase()public static int toUpperCase(int codePoint)
Note thatCharacter.isUpperCase(Character.toUpperCase(codePoint)) does not always returntrue for some ranges of characters, particularly those that are symbols or ideographs.
In general,String.toUpperCase() should be used to map characters to uppercase.String case mapping methods have several benefits overCharacter case mapping methods.String case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharacter case mapping methods cannot.
codePoint - the character (Unicode code point) to be converted.isUpperCase(int),String.toUpperCase()public static char toTitleCase(char ch)
char argument is already a titlecasechar, the samechar value will be returned. Note thatCharacter.isTitleCase(Character.toTitleCase(ch)) does not always returntrue for some ranges of characters.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thetoTitleCase(int) method.
ch - the character to be converted.isTitleCase(char),toLowerCase(char),toUpperCase(char)public static int toTitleCase(int codePoint)
Note thatCharacter.isTitleCase(Character.toTitleCase(codePoint)) does not always returntrue for some ranges of characters.
codePoint - the character (Unicode code point) to be converted.isTitleCase(int),toLowerCase(int),toUpperCase(int)public static int digit(char ch, int radix)
ch in the specified radix. If the radix is not in the rangeMIN_RADIX ≤radix ≤MAX_RADIX or if the value ofch is not a valid digit in the specified radix,-1 is returned. A character is a valid digit if at least one of the following is true:
isDigit istrue of the character and the Unicode decimal digit value of the character (or its single-character decomposition) is less than the specified radix. In this case the decimal digit value is returned.'A' through'Z' and its code is less thanradix + 'A' - 10. In this case,ch - 'A' + 10 is returned.'a' through'z' and its code is less thanradix + 'a' - 10. In this case,ch - 'a' + 10 is returned.'\uFF21') through Z ('\uFF3A') and its code is less thanradix + '\uFF21' - 10. In this case,ch - '\uFF21' + 10 is returned.'\uFF41') through z ('\uFF5A') and its code is less thanradix + '\uFF41' - 10. In this case,ch - '\uFF41' + 10 is returned.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thedigit(int, int) method.
ch - the character to be converted.radix - the radix.forDigit(int, int),isDigit(char)public static int digit(int codePoint, int radix)
If the radix is not in the rangeMIN_RADIX ≤radix ≤MAX_RADIX or if the character is not a valid digit in the specified radix,-1 is returned. A character is a valid digit if at least one of the following is true:
isDigit(codePoint) istrue of the character and the Unicode decimal digit value of the character (or its single-character decomposition) is less than the specified radix. In this case the decimal digit value is returned.'A' through'Z' and its code is less thanradix + 'A' - 10. In this case,codePoint - 'A' + 10 is returned.'a' through'z' and its code is less thanradix + 'a' - 10. In this case,codePoint - 'a' + 10 is returned.'\uFF21') through Z ('\uFF3A') and its code is less thanradix + '\uFF21' - 10. In this case,codePoint - '\uFF21' + 10 is returned.'\uFF41') through z ('\uFF5A') and its code is less thanradix + '\uFF41'- 10. In this case,codePoint - '\uFF41' + 10 is returned.codePoint - the character (Unicode code point) to be converted.radix - the radix.forDigit(int, int),isDigit(int)public static int getNumericValue(char ch)
int value that the specified Unicode character represents. For example, the character'\u216C' (the roman numeral fifty) will return an int with a value of 50. The letters A-Z in their uppercase ('\u0041' through'\u005A'), lowercase ('\u0061' through'\u007A'), and full width variant ('\uFF21' through'\uFF3A' and'\uFF41' through'\uFF5A') forms have numeric values from 10 through 35. This is independent of the Unicode specification, which does not assign numeric values to thesechar values.
If the character does not have a numeric value, then -1 is returned. If the character has a numeric value that cannot be represented as a nonnegative integer (for example, a fractional value), then -2 is returned.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thegetNumericValue(int) method.
ch - the character to be converted.int value; -2 if the character has a numeric value that is not a nonnegative integer; -1 if the character has no numeric value.forDigit(int, int),isDigit(char)public static int getNumericValue(int codePoint)
int value that the specified character (Unicode code point) represents. For example, the character'\u216C' (the Roman numeral fifty) will return anint with a value of 50. The letters A-Z in their uppercase ('\u0041' through'\u005A'), lowercase ('\u0061' through'\u007A'), and full width variant ('\uFF21' through'\uFF3A' and'\uFF41' through'\uFF5A') forms have numeric values from 10 through 35. This is independent of the Unicode specification, which does not assign numeric values to thesechar values.
If the character does not have a numeric value, then -1 is returned. If the character has a numeric value that cannot be represented as a nonnegative integer (for example, a fractional value), then -2 is returned.
codePoint - the character (Unicode code point) to be converted.int value; -2 if the character has a numeric value that is not a nonnegative integer; -1 if the character has no numeric value.forDigit(int, int),isDigit(int)@Deprecatedpublic static boolean isSpace(char ch)
true for the following five characters only:'\t' | U+0009 | HORIZONTAL TABULATION |
'\n' | U+000A | NEW LINE |
'\f' | U+000C | FORM FEED |
'\r' | U+000D | CARRIAGE RETURN |
' ' | U+0020 | SPACE |
ch - the character to be tested.true if the character is ISO-LATIN-1 white space;false otherwise.isSpaceChar(char),isWhitespace(char)public static boolean isSpaceChar(char ch)
SPACE_SEPARATORLINE_SEPARATORPARAGRAPH_SEPARATORNote: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisSpaceChar(int) method.
ch - the character to be tested.true if the character is a space character;false otherwise.isWhitespace(char)public static boolean isSpaceChar(int codePoint)
codePoint - the character (Unicode code point) to be tested.true if the character is a space character;false otherwise.isWhitespace(int)public static boolean isWhitespace(char ch)
SPACE_SEPARATOR,LINE_SEPARATOR, orPARAGRAPH_SEPARATOR) but is not also a non-breaking space ('\u00A0','\u2007','\u202F').'\t', U+0009 HORIZONTAL TABULATION.'\n', U+000A LINE FEED.'\u000B', U+000B VERTICAL TABULATION.'\f', U+000C FORM FEED.'\r', U+000D CARRIAGE RETURN.'\u001C', U+001C FILE SEPARATOR.'\u001D', U+001D GROUP SEPARATOR.'\u001E', U+001E RECORD SEPARATOR.'\u001F', U+001F UNIT SEPARATOR.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisWhitespace(int) method.
ch - the character to be tested.true if the character is a Java whitespace character;false otherwise.isSpaceChar(char)public static boolean isWhitespace(int codePoint)
SPACE_SEPARATOR,LINE_SEPARATOR, orPARAGRAPH_SEPARATOR) but is not also a non-breaking space ('\u00A0','\u2007','\u202F').'\t', U+0009 HORIZONTAL TABULATION.'\n', U+000A LINE FEED.'\u000B', U+000B VERTICAL TABULATION.'\f', U+000C FORM FEED.'\r', U+000D CARRIAGE RETURN.'\u001C', U+001C FILE SEPARATOR.'\u001D', U+001D GROUP SEPARATOR.'\u001E', U+001E RECORD SEPARATOR.'\u001F', U+001F UNIT SEPARATOR.codePoint - the character (Unicode code point) to be tested.true if the character is a Java whitespace character;false otherwise.isSpaceChar(int)public static boolean isISOControl(char ch)
'\u0000' through'\u001F' or in the range'\u007F' through'\u009F'.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisISOControl(int) method.
ch - the character to be tested.true if the character is an ISO control character;false otherwise.isSpaceChar(char),isWhitespace(char)public static boolean isISOControl(int codePoint)
'\u0000' through'\u001F' or in the range'\u007F' through'\u009F'.codePoint - the character (Unicode code point) to be tested.true if the character is an ISO control character;false otherwise.isSpaceChar(int),isWhitespace(int)public static int getType(char ch)
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thegetType(int) method.
ch - the character to be tested.int representing the character's general category.COMBINING_SPACING_MARK,CONNECTOR_PUNCTUATION,CONTROL,CURRENCY_SYMBOL,DASH_PUNCTUATION,DECIMAL_DIGIT_NUMBER,ENCLOSING_MARK,END_PUNCTUATION,FINAL_QUOTE_PUNCTUATION,FORMAT,INITIAL_QUOTE_PUNCTUATION,LETTER_NUMBER,LINE_SEPARATOR,LOWERCASE_LETTER,MATH_SYMBOL,MODIFIER_LETTER,MODIFIER_SYMBOL,NON_SPACING_MARK,OTHER_LETTER,OTHER_NUMBER,OTHER_PUNCTUATION,OTHER_SYMBOL,PARAGRAPH_SEPARATOR,PRIVATE_USE,SPACE_SEPARATOR,START_PUNCTUATION,SURROGATE,TITLECASE_LETTER,UNASSIGNED,UPPERCASE_LETTERpublic static int getType(int codePoint)
codePoint - the character (Unicode code point) to be tested.int representing the character's general category.COMBINING_SPACING_MARK,CONNECTOR_PUNCTUATION,CONTROL,CURRENCY_SYMBOL,DASH_PUNCTUATION,DECIMAL_DIGIT_NUMBER,ENCLOSING_MARK,END_PUNCTUATION,FINAL_QUOTE_PUNCTUATION,FORMAT,INITIAL_QUOTE_PUNCTUATION,LETTER_NUMBER,LINE_SEPARATOR,LOWERCASE_LETTER,MATH_SYMBOL,MODIFIER_LETTER,MODIFIER_SYMBOL,NON_SPACING_MARK,OTHER_LETTER,OTHER_NUMBER,OTHER_PUNCTUATION,OTHER_SYMBOL,PARAGRAPH_SEPARATOR,PRIVATE_USE,SPACE_SEPARATOR,START_PUNCTUATION,SURROGATE,TITLECASE_LETTER,UNASSIGNED,UPPERCASE_LETTERpublic static char forDigit(int digit, int radix)
radix is not a valid radix, or the value ofdigit is not a valid digit in the specified radix, the null character ('\u0000') is returned. Theradix argument is valid if it is greater than or equal toMIN_RADIX and less than or equal toMAX_RADIX. Thedigit argument is valid if0 <= digit < radix.
If the digit is less than 10, then'0' + digit is returned. Otherwise, the value'a' + digit - 10 is returned.
digit - the number to convert to a character.radix - the radix.char representation of the specified digit in the specified radix.MIN_RADIX,MAX_RADIX,digit(char, int)public static byte getDirectionality(char ch)
char values isDIRECTIONALITY_UNDEFINED.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use thegetDirectionality(int) method.
ch -char for which the directionality property is requested.char value.DIRECTIONALITY_UNDEFINED,DIRECTIONALITY_LEFT_TO_RIGHT,DIRECTIONALITY_RIGHT_TO_LEFT,DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC,DIRECTIONALITY_EUROPEAN_NUMBER,DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR,DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR,DIRECTIONALITY_ARABIC_NUMBER,DIRECTIONALITY_COMMON_NUMBER_SEPARATOR,DIRECTIONALITY_NONSPACING_MARK,DIRECTIONALITY_BOUNDARY_NEUTRAL,DIRECTIONALITY_PARAGRAPH_SEPARATOR,DIRECTIONALITY_SEGMENT_SEPARATOR,DIRECTIONALITY_WHITESPACE,DIRECTIONALITY_OTHER_NEUTRALS,DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING,DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE,DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING,DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE,DIRECTIONALITY_POP_DIRECTIONAL_FORMATpublic static byte getDirectionality(int codePoint)
DIRECTIONALITY_UNDEFINED.codePoint - the character (Unicode code point) for which the directionality property is requested.DIRECTIONALITY_UNDEFINED,DIRECTIONALITY_LEFT_TO_RIGHT,DIRECTIONALITY_RIGHT_TO_LEFT,DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC,DIRECTIONALITY_EUROPEAN_NUMBER,DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR,DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR,DIRECTIONALITY_ARABIC_NUMBER,DIRECTIONALITY_COMMON_NUMBER_SEPARATOR,DIRECTIONALITY_NONSPACING_MARK,DIRECTIONALITY_BOUNDARY_NEUTRAL,DIRECTIONALITY_PARAGRAPH_SEPARATOR,DIRECTIONALITY_SEGMENT_SEPARATOR,DIRECTIONALITY_WHITESPACE,DIRECTIONALITY_OTHER_NEUTRALS,DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING,DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE,DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING,DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE,DIRECTIONALITY_POP_DIRECTIONAL_FORMATpublic static boolean isMirrored(char ch)
'\u0028' LEFT PARENTHESIS is semantically defined to be anopening parenthesis. This will appear as a "(" in text that is left-to-right but as a ")" in text that is right-to-left.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use theisMirrored(int) method.
ch -char for which the mirrored property is requestedtrue if the char is mirrored,false if thechar is not mirrored or is not defined.public static boolean isMirrored(int codePoint)
'\u0028' LEFT PARENTHESIS is semantically defined to be anopening parenthesis. This will appear as a "(" in text that is left-to-right but as a ")" in text that is right-to-left.codePoint - the character (Unicode code point) to be tested.true if the character is mirrored,false if the character is not mirrored or is not defined.public int compareTo(Character anotherCharacter)
Character objects numerically.compareTo in interface Comparable<Character>anotherCharacter - theCharacter to be compared.0 if the argumentCharacter is equal to thisCharacter; a value less than0 if thisCharacter is numerically less than theCharacter argument; and a value greater than0 if thisCharacter is numerically greater than theCharacter argument (unsigned comparison). Note that this is strictly a numerical comparison; it is not locale-dependent.public static int compare(char x, char y)
char values numerically. The value returned is identical to what would be returned by:Character.valueOf(x).compareTo(Character.valueOf(y))
x - the firstchar to comparey - the secondchar to compare0 ifx == y; a value less than0 ifx < y; and a value greater than0 ifx > ypublic static char reverseBytes(char ch)
ch - Thechar of which to reverse the byte order.public static String getName(int codePoint)
codePoint, or null if the code point isunassigned.Note: if the specified character is not assigned a name by theUnicodeData file (part of the Unicode Character Database maintained by the Unicode Consortium), the returned name is the same as the result of expression.
Character.UnicodeBlock.of(codePoint).toString().replace('_', ' ') + " " + Integer.toHexString(codePoint).toUpperCase(Locale.ENGLISH);codePoint - the character (Unicode code point)IllegalArgumentException - if the specifiedcodePoint is not a valid Unicode code point.