- All Implemented Interfaces:
Serializable,Comparable<Character>,Constable
Character class wraps a value of the primitive
type char in an object. An object of class
Character contains a single field whose type is
char.
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.
Unicode Conformance
The fields and methods of class Character are defined in terms
of character information from the Unicode Standard, specifically the
UnicodeData 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 at
http://www.unicode.org.
Character information is based on the Unicode Standard, version 13.0.
The Java platform has supported different versions of the Unicode Standard over time. Upgrades to newer versions of the Unicode Standard occurred in the following Java releases, each indicating the new version:
| Java release | Unicode version |
|---|---|
| Java SE 15 | Unicode 13.0 |
| Java SE 13 | Unicode 12.1 |
| Java SE 12 | Unicode 11.0 |
| Java SE 11 | Unicode 10.0 |
| Java SE 9 | Unicode 8.0 |
| Java SE 8 | Unicode 6.2 |
| Java SE 7 | Unicode 6.0 |
| Java SE 5.0 | Unicode 4.0 |
| Java SE 1.4 | Unicode 3.0 |
| JDK 1.1 | Unicode 2.0 |
| JDK 1.0.2 | Unicode 1.1.5 |
Unicode Character Representations
The char data type (and therefore the value that a
Character 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 legal code points is now
U+0000 to U+10FFFF, known as Unicode 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 the Basic Multilingual Plane (BMP).
Characters whose code points are greater
than U+FFFF are called supplementary characters. The Java
platform uses the UTF-16 representation in char arrays and
in the String and StringBuffer classes. In
this representation, supplementary characters are represented as a pair
of char values, the first from the high-surrogates
range, (\uD800-\uDBFF), the second from the
low-surrogates range (\uDC00-\uDFFF).
A char value, therefore, represents Basic
Multilingual Plane (BMP) code points, including the surrogate
code points, or code units of the UTF-16 encoding. An
int value represents all Unicode code points,
including supplementary code points. The lower (least significant)
21 bits of int 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 surrogate char values is
as follows:
- The methods that only accept a
charvalue cannot support supplementary characters. They treatcharvalues 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. - The methods that accept an
intvalue support all Unicode characters, including supplementary characters. For example,Character.isLetter(0x2F81A)returnstruebecause 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,
and Unicode code unit is used for 16-bit
char values that are code units of the UTF-16
encoding. For more information on Unicode terminology, refer to the
Unicode Glossary.
This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail.
- Since:
- 1.0
- See Also:
-
Nested Class Summary
Nested ClassesModifier and TypeClassDescriptionstatic classInstances of this class represent particular subsets of the Unicode character set.static final classA family of character subsets representing the character blocks in the Unicode specification.static enumA family of character subsets representing the character scripts defined in the Unicode Standard Annex #24: Script Names. -
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final intThe number of bytes used to represent acharvalue in unsigned binary form.static final byteGeneral category "Mc" in the Unicode specification.static final byteGeneral category "Pc" in the Unicode specification.static final byteGeneral category "Cc" in the Unicode specification.static final byteGeneral category "Sc" in the Unicode specification.static final byteGeneral category "Pd" in the Unicode specification.static final byteGeneral category "Nd" in the Unicode specification.static final byteWeak bidirectional character type "AN" in the Unicode specification.static final byteWeak bidirectional character type "BN" in the Unicode specification.static final byteWeak bidirectional character type "CS" in the Unicode specification.static final byteWeak bidirectional character type "EN" in the Unicode specification.static final byteWeak bidirectional character type "ES" in the Unicode specification.static final byteWeak bidirectional character type "ET" in the Unicode specification.static final byteWeak bidirectional character type "FSI" in the Unicode specification.static final byteStrong bidirectional character type "L" in the Unicode specification.static final byteStrong bidirectional character type "LRE" in the Unicode specification.static final byteWeak bidirectional character type "LRI" in the Unicode specification.static final byteStrong bidirectional character type "LRO" in the Unicode specification.static final byteWeak bidirectional character type "NSM" in the Unicode specification.static final byteNeutral bidirectional character type "ON" in the Unicode specification.static final byteNeutral bidirectional character type "B" in the Unicode specification.static final byteWeak bidirectional character type "PDF" in the Unicode specification.static final byteWeak bidirectional character type "PDI" in the Unicode specification.static final byteStrong bidirectional character type "R" in the Unicode specification.static final byteStrong bidirectional character type "AL" in the Unicode specification.static final byteStrong bidirectional character type "RLE" in the Unicode specification.static final byteWeak bidirectional character type "RLI" in the Unicode specification.static final byteStrong bidirectional character type "RLO" in the Unicode specification.static final byteNeutral bidirectional character type "S" in the Unicode specification.static final byteUndefined bidirectional character type.static final byteNeutral bidirectional character type "WS" in the Unicode specification.static final byteGeneral category "Me" in the Unicode specification.static final byteGeneral category "Pe" in the Unicode specification.static final byteGeneral category "Pf" in the Unicode specification.static final byteGeneral category "Cf" in the Unicode specification.static final byteGeneral category "Pi" in the Unicode specification.static final byteGeneral category "Nl" in the Unicode specification.static final byteGeneral category "Zl" in the Unicode specification.static final byteGeneral category "Ll" in the Unicode specification.static final byteGeneral category "Sm" in the Unicode specification.static final intThe maximum value of a Unicode code point, constantU+10FFFF.static final charThe maximum value of a Unicode high-surrogate code unit in the UTF-16 encoding, constant'\uDBFF'.static final charThe maximum value of a Unicode low-surrogate code unit in the UTF-16 encoding, constant'\uDFFF'.static final intThe maximum radix available for conversion to and from strings.static final charThe maximum value of a Unicode surrogate code unit in the UTF-16 encoding, constant'\uDFFF'.static final charThe constant value of this field is the largest value of typechar,'\uFFFF'.static final intThe minimum value of a Unicode code point, constantU+0000.static final charThe minimum value of a Unicode high-surrogate code unit in the UTF-16 encoding, constant'\uD800'.static final charThe minimum value of a Unicode low-surrogate code unit in the UTF-16 encoding, constant'\uDC00'.static final intThe minimum radix available for conversion to and from strings.static final intThe minimum value of a Unicode supplementary code point, constantU+10000.static final charThe minimum value of a Unicode surrogate code unit in the UTF-16 encoding, constant'\uD800'.static final charThe constant value of this field is the smallest value of typechar,'\u0000'.static final byteGeneral category "Lm" in the Unicode specification.static final byteGeneral category "Sk" in the Unicode specification.static final byteGeneral category "Mn" in the Unicode specification.static final byteGeneral category "Lo" in the Unicode specification.static final byteGeneral category "No" in the Unicode specification.static final byteGeneral category "Po" in the Unicode specification.static final byteGeneral category "So" in the Unicode specification.static final byteGeneral category "Zp" in the Unicode specification.static final byteGeneral category "Co" in the Unicode specification.static final intThe number of bits used to represent acharvalue in unsigned binary form, constant16.static final byteGeneral category "Zs" in the Unicode specification.static final byteGeneral category "Ps" in the Unicode specification.static final byteGeneral category "Cs" in the Unicode specification.static final byteGeneral category "Lt" in the Unicode specification.TheClassinstance representing the primitive typechar.static final byteGeneral category "Cn" in the Unicode specification.static final byteGeneral category "Lu" in the Unicode specification. -
Constructor Summary
ConstructorsConstructorDescriptionCharacter(char value) Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. -
Method Summary
Modifier and TypeMethodDescriptionstatic intcharCount(int codePoint) Determines the number ofcharvalues needed to represent the specified character (Unicode code point).charReturns the value of thisCharacterobject.static intcodePointAt(char[] a, int index) Returns the code point at the given index of thechararray.static intcodePointAt(char[] a, int index, int limit) Returns the code point at the given index of thechararray, where only array elements withindexless thanlimitcan be used.static intcodePointAt(CharSequence seq, int index) Returns the code point at the given index of theCharSequence.static intcodePointBefore(char[] a, int index) Returns the code point preceding the given index of thechararray.static intcodePointBefore(char[] a, int index, int start) Returns the code point preceding the given index of thechararray, where only array elements withindexgreater than or equal tostartcan be used.static intcodePointBefore(CharSequence seq, int index) Returns the code point preceding the given index of theCharSequence.static intcodePointCount(char[] a, int offset, int count) Returns the number of Unicode code points in a subarray of thechararray argument.static intcodePointCount(CharSequence seq, int beginIndex, int endIndex) Returns the number of Unicode code points in the text range of the specified char sequence.static intcodePointOf(String name) Returns the code point value of the Unicode character specified by the given Unicode character name.static intcompare(char x, char y) Compares twocharvalues numerically.intCompares twoCharacterobjects numerically.Returns anOptionalcontaining the nominal descriptor for this instance.static intdigit(char ch, int radix) Returns the numeric value of the characterchin the specified radix.static intdigit(int codePoint, int radix) Returns the numeric value of the specified character (Unicode code point) in the specified radix.booleanCompares this object against the specified object.static charforDigit(int digit, int radix) Determines the character representation for a specific digit in the specified radix.static bytegetDirectionality(char ch) Returns the Unicode directionality property for the given character.static bytegetDirectionality(int codePoint) Returns the Unicode directionality property for the given character (Unicode code point).static StringgetName(int codePoint) Returns the Unicode name of the specified charactercodePoint, or null if the code point isunassigned.static intgetNumericValue(char ch) Returns theintvalue that the specified Unicode character represents.static intgetNumericValue(int codePoint) Returns theintvalue that the specified character (Unicode code point) represents.static intgetType(char ch) Returns a value indicating a character's general category.static intgetType(int codePoint) Returns a value indicating a character's general category.inthashCode()Returns a hash code for thisCharacter; equal to the result of invokingcharValue().static inthashCode(char value) Returns a hash code for acharvalue; compatible withCharacter.hashCode().static charhighSurrogate(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 booleanisAlphabetic(int codePoint) Determines if the specified character (Unicode code point) is alphabetic.static booleanisBmpCodePoint(int codePoint) Determines whether the specified character (Unicode code point) is in the Basic Multilingual Plane (BMP).static booleanisDefined(char ch) Determines if a character is defined in Unicode.static booleanisDefined(int codePoint) Determines if a character (Unicode code point) is defined in Unicode.static booleanisDigit(char ch) Determines if the specified character is a digit.static booleanisDigit(int codePoint) Determines if the specified character (Unicode code point) is a digit.static booleanisHighSurrogate(char ch) Determines if the givencharvalue is a Unicode high-surrogate code unit (also known as leading-surrogate code unit).static booleanisIdentifierIgnorable(char ch) Determines if the specified character should be regarded as an ignorable character in a Java identifier or a Unicode identifier.static booleanisIdentifierIgnorable(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 booleanisIdeographic(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 booleanisISOControl(char ch) Determines if the specified character is an ISO control character.static booleanisISOControl(int codePoint) Determines if the referenced character (Unicode code point) is an ISO control character.static booleanisJavaIdentifierPart(char ch) Determines if the specified character may be part of a Java identifier as other than the first character.static booleanisJavaIdentifierPart(int codePoint) Determines if the character (Unicode code point) may be part of a Java identifier as other than the first character.static booleanisJavaIdentifierStart(char ch) Determines if the specified character is permissible as the first character in a Java identifier.static booleanisJavaIdentifierStart(int codePoint) Determines if the character (Unicode code point) is permissible as the first character in a Java identifier.static booleanisJavaLetter(char ch) Deprecated.Replaced by isJavaIdentifierStart(char).static booleanisJavaLetterOrDigit(char ch) Deprecated.Replaced by isJavaIdentifierPart(char).static booleanisLetter(char ch) Determines if the specified character is a letter.static booleanisLetter(int codePoint) Determines if the specified character (Unicode code point) is a letter.static booleanisLetterOrDigit(char ch) Determines if the specified character is a letter or digit.static booleanisLetterOrDigit(int codePoint) Determines if the specified character (Unicode code point) is a letter or digit.static booleanisLowerCase(char ch) Determines if the specified character is a lowercase character.static booleanisLowerCase(int codePoint) Determines if the specified character (Unicode code point) is a lowercase character.static booleanisLowSurrogate(char ch) Determines if the givencharvalue is a Unicode low-surrogate code unit (also known as trailing-surrogate code unit).static booleanisMirrored(char ch) Determines whether the character is mirrored according to the Unicode specification.static booleanisMirrored(int codePoint) Determines whether the specified character (Unicode code point) is mirrored according to the Unicode specification.static booleanisSpace(char ch) Deprecated.Replaced by isWhitespace(char).static booleanisSpaceChar(char ch) Determines if the specified character is a Unicode space character.static booleanisSpaceChar(int codePoint) Determines if the specified character (Unicode code point) is a Unicode space character.static booleanisSupplementaryCodePoint(int codePoint) Determines whether the specified character (Unicode code point) is in the supplementary character range.static booleanisSurrogate(char ch) Determines if the givencharvalue is a Unicode surrogate code unit.static booleanisSurrogatePair(char high, char low) Determines whether the specified pair ofcharvalues is a valid Unicode surrogate pair.static booleanisTitleCase(char ch) Determines if the specified character is a titlecase character.static booleanisTitleCase(int codePoint) Determines if the specified character (Unicode code point) is a titlecase character.static booleanisUnicodeIdentifierPart(char ch) Determines if the specified character may be part of a Unicode identifier as other than the first character.static booleanisUnicodeIdentifierPart(int codePoint) Determines if the specified character (Unicode code point) may be part of a Unicode identifier as other than the first character.static booleanisUnicodeIdentifierStart(char ch) Determines if the specified character is permissible as the first character in a Unicode identifier.static booleanisUnicodeIdentifierStart(int codePoint) Determines if the specified character (Unicode code point) is permissible as the first character in a Unicode identifier.static booleanisUpperCase(char ch) Determines if the specified character is an uppercase character.static booleanisUpperCase(int codePoint) Determines if the specified character (Unicode code point) is an uppercase character.static booleanisValidCodePoint(int codePoint) Determines whether the specified code point is a valid Unicode code point value.static booleanisWhitespace(char ch) Determines if the specified character is white space according to Java.static booleanisWhitespace(int codePoint) Determines if the specified character (Unicode code point) is white space according to Java.static charlowSurrogate(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 intoffsetByCodePoints(char[] a, int start, int count, int index, int codePointOffset) Returns the index within the givencharsubarray that is offset from the givenindexbycodePointOffsetcode points.static intoffsetByCodePoints(CharSequence seq, int index, int codePointOffset) Returns the index within the given char sequence that is offset from the givenindexbycodePointOffsetcode points.static charreverseBytes(char ch) Returns the value obtained by reversing the order of the bytes in the specifiedcharvalue.static char[]toChars(int codePoint) Converts the specified character (Unicode code point) to its UTF-16 representation stored in achararray.static inttoChars(int codePoint, char[] dst, int dstIndex) Converts the specified character (Unicode code point) to its UTF-16 representation.static inttoCodePoint(char high, char low) Converts the specified surrogate pair to its supplementary code point value.static chartoLowerCase(char ch) Converts the character argument to lowercase using case mapping information from the UnicodeData file.static inttoLowerCase(int codePoint) Converts the character (Unicode code point) argument to lowercase using case mapping information from the UnicodeData file.toString()Returns aStringobject representing thisCharacter's value.static StringtoString(char c) Returns aStringobject representing the specifiedchar.static StringtoString(int codePoint) Returns aStringobject representing the specified character (Unicode code point).static chartoTitleCase(char ch) Converts the character argument to titlecase using case mapping information from the UnicodeData file.static inttoTitleCase(int codePoint) Converts the character (Unicode code point) argument to titlecase using case mapping information from the UnicodeData file.static chartoUpperCase(char ch) Converts the character argument to uppercase using case mapping information from the UnicodeData file.static inttoUpperCase(int codePoint) Converts the character (Unicode code point) argument to uppercase using case mapping information from the UnicodeData file.static CharactervalueOf(char c) Returns aCharacterinstance representing the specifiedcharvalue.
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Field Details
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MIN_RADIX
public static final int MIN_RADIXThe minimum radix available for conversion to and from strings. The constant value of this field is the smallest value permitted for the radix argument in radix-conversion methods such as thedigitmethod, theforDigitmethod, and thetoStringmethod of classInteger. -
MAX_RADIX
public static final int MAX_RADIXThe maximum radix available for conversion to and from strings. The constant value of this field is the largest value permitted for the radix argument in radix-conversion methods such as thedigitmethod, theforDigitmethod, and thetoStringmethod of classInteger. -
MIN_VALUE
public static final char MIN_VALUEThe constant value of this field is the smallest value of typechar,'\u0000'.- Since:
- 1.0.2
- See Also:
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MAX_VALUE
public static final char MAX_VALUEThe constant value of this field is the largest value of typechar,'\uFFFF'.- Since:
- 1.0.2
- See Also:
-
TYPE
TheClassinstance representing the primitive typechar.- Since:
- 1.1
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UNASSIGNED
public static final byte UNASSIGNEDGeneral category "Cn" in the Unicode specification.- Since:
- 1.1
- See Also:
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UPPERCASE_LETTER
public static final byte UPPERCASE_LETTERGeneral category "Lu" in the Unicode specification.- Since:
- 1.1
- See Also:
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LOWERCASE_LETTER
public static final byte LOWERCASE_LETTERGeneral category "Ll" in the Unicode specification.- Since:
- 1.1
- See Also:
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TITLECASE_LETTER
public static final byte TITLECASE_LETTERGeneral category "Lt" in the Unicode specification.- Since:
- 1.1
- See Also:
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MODIFIER_LETTER
public static final byte MODIFIER_LETTERGeneral category "Lm" in the Unicode specification.- Since:
- 1.1
- See Also:
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OTHER_LETTER
public static final byte OTHER_LETTERGeneral category "Lo" in the Unicode specification.- Since:
- 1.1
- See Also:
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NON_SPACING_MARK
public static final byte NON_SPACING_MARKGeneral category "Mn" in the Unicode specification.- Since:
- 1.1
- See Also:
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ENCLOSING_MARK
public static final byte ENCLOSING_MARKGeneral category "Me" in the Unicode specification.- Since:
- 1.1
- See Also:
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COMBINING_SPACING_MARK
public static final byte COMBINING_SPACING_MARKGeneral category "Mc" in the Unicode specification.- Since:
- 1.1
- See Also:
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DECIMAL_DIGIT_NUMBER
public static final byte DECIMAL_DIGIT_NUMBERGeneral category "Nd" in the Unicode specification.- Since:
- 1.1
- See Also:
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LETTER_NUMBER
public static final byte LETTER_NUMBERGeneral category "Nl" in the Unicode specification.- Since:
- 1.1
- See Also:
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OTHER_NUMBER
public static final byte OTHER_NUMBERGeneral category "No" in the Unicode specification.- Since:
- 1.1
- See Also:
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SPACE_SEPARATOR
public static final byte SPACE_SEPARATORGeneral category "Zs" in the Unicode specification.- Since:
- 1.1
- See Also:
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LINE_SEPARATOR
public static final byte LINE_SEPARATORGeneral category "Zl" in the Unicode specification.- Since:
- 1.1
- See Also:
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PARAGRAPH_SEPARATOR
public static final byte PARAGRAPH_SEPARATORGeneral category "Zp" in the Unicode specification.- Since:
- 1.1
- See Also:
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CONTROL
public static final byte CONTROLGeneral category "Cc" in the Unicode specification.- Since:
- 1.1
- See Also:
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FORMAT
public static final byte FORMATGeneral category "Cf" in the Unicode specification.- Since:
- 1.1
- See Also:
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PRIVATE_USE
public static final byte PRIVATE_USEGeneral category "Co" in the Unicode specification.- Since:
- 1.1
- See Also:
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SURROGATE
public static final byte SURROGATEGeneral category "Cs" in the Unicode specification.- Since:
- 1.1
- See Also:
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DASH_PUNCTUATION
public static final byte DASH_PUNCTUATIONGeneral category "Pd" in the Unicode specification.- Since:
- 1.1
- See Also:
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START_PUNCTUATION
public static final byte START_PUNCTUATIONGeneral category "Ps" in the Unicode specification.- Since:
- 1.1
- See Also:
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END_PUNCTUATION
public static final byte END_PUNCTUATIONGeneral category "Pe" in the Unicode specification.- Since:
- 1.1
- See Also:
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CONNECTOR_PUNCTUATION
public static final byte CONNECTOR_PUNCTUATIONGeneral category "Pc" in the Unicode specification.- Since:
- 1.1
- See Also:
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OTHER_PUNCTUATION
public static final byte OTHER_PUNCTUATIONGeneral category "Po" in the Unicode specification.- Since:
- 1.1
- See Also:
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MATH_SYMBOL
public static final byte MATH_SYMBOLGeneral category "Sm" in the Unicode specification.- Since:
- 1.1
- See Also:
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CURRENCY_SYMBOL
public static final byte CURRENCY_SYMBOLGeneral category "Sc" in the Unicode specification.- Since:
- 1.1
- See Also:
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MODIFIER_SYMBOL
public static final byte MODIFIER_SYMBOLGeneral category "Sk" in the Unicode specification.- Since:
- 1.1
- See Also:
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OTHER_SYMBOL
public static final byte OTHER_SYMBOLGeneral category "So" in the Unicode specification.- Since:
- 1.1
- See Also:
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INITIAL_QUOTE_PUNCTUATION
public static final byte INITIAL_QUOTE_PUNCTUATIONGeneral category "Pi" in the Unicode specification.- Since:
- 1.4
- See Also:
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FINAL_QUOTE_PUNCTUATION
public static final byte FINAL_QUOTE_PUNCTUATIONGeneral category "Pf" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_UNDEFINED
public static final byte DIRECTIONALITY_UNDEFINEDUndefined bidirectional character type. Undefinedcharvalues have undefined directionality in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_LEFT_TO_RIGHT
public static final byte DIRECTIONALITY_LEFT_TO_RIGHTStrong bidirectional character type "L" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_RIGHT_TO_LEFT
public static final byte DIRECTIONALITY_RIGHT_TO_LEFTStrong bidirectional character type "R" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_ARABICStrong bidirectional character type "AL" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_EUROPEAN_NUMBER
public static final byte DIRECTIONALITY_EUROPEAN_NUMBERWeak bidirectional character type "EN" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATORWeak bidirectional character type "ES" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATORWeak bidirectional character type "ET" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_ARABIC_NUMBER
public static final byte DIRECTIONALITY_ARABIC_NUMBERWeak bidirectional character type "AN" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_COMMON_NUMBER_SEPARATOR
public static final byte DIRECTIONALITY_COMMON_NUMBER_SEPARATORWeak bidirectional character type "CS" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_NONSPACING_MARK
public static final byte DIRECTIONALITY_NONSPACING_MARKWeak bidirectional character type "NSM" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_BOUNDARY_NEUTRAL
public static final byte DIRECTIONALITY_BOUNDARY_NEUTRALWeak bidirectional character type "BN" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_PARAGRAPH_SEPARATOR
public static final byte DIRECTIONALITY_PARAGRAPH_SEPARATORNeutral bidirectional character type "B" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_SEGMENT_SEPARATOR
public static final byte DIRECTIONALITY_SEGMENT_SEPARATORNeutral bidirectional character type "S" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_WHITESPACE
public static final byte DIRECTIONALITY_WHITESPACENeutral bidirectional character type "WS" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_OTHER_NEUTRALS
public static final byte DIRECTIONALITY_OTHER_NEUTRALSNeutral bidirectional character type "ON" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDINGStrong bidirectional character type "LRE" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDEStrong bidirectional character type "LRO" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDINGStrong bidirectional character type "RLE" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDEStrong bidirectional character type "RLO" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_POP_DIRECTIONAL_FORMAT
public static final byte DIRECTIONALITY_POP_DIRECTIONAL_FORMATWeak bidirectional character type "PDF" in the Unicode specification.- Since:
- 1.4
- See Also:
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DIRECTIONALITY_LEFT_TO_RIGHT_ISOLATE
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_ISOLATEWeak bidirectional character type "LRI" in the Unicode specification.- Since:
- 9
- See Also:
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DIRECTIONALITY_RIGHT_TO_LEFT_ISOLATE
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_ISOLATEWeak bidirectional character type "RLI" in the Unicode specification.- Since:
- 9
- See Also:
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DIRECTIONALITY_FIRST_STRONG_ISOLATE
public static final byte DIRECTIONALITY_FIRST_STRONG_ISOLATEWeak bidirectional character type "FSI" in the Unicode specification.- Since:
- 9
- See Also:
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DIRECTIONALITY_POP_DIRECTIONAL_ISOLATE
public static final byte DIRECTIONALITY_POP_DIRECTIONAL_ISOLATEWeak bidirectional character type "PDI" in the Unicode specification.- Since:
- 9
- See Also:
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MIN_HIGH_SURROGATE
public static final char MIN_HIGH_SURROGATEThe minimum value of a Unicode high-surrogate code unit in the UTF-16 encoding, constant'\uD800'. A high-surrogate is also known as a leading-surrogate.- Since:
- 1.5
- See Also:
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MAX_HIGH_SURROGATE
public static final char MAX_HIGH_SURROGATEThe maximum value of a Unicode high-surrogate code unit in the UTF-16 encoding, constant'\uDBFF'. A high-surrogate is also known as a leading-surrogate.- Since:
- 1.5
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MIN_LOW_SURROGATE
public static final char MIN_LOW_SURROGATEThe minimum value of a Unicode low-surrogate code unit in the UTF-16 encoding, constant'\uDC00'. A low-surrogate is also known as a trailing-surrogate.- Since:
- 1.5
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MAX_LOW_SURROGATE
public static final char MAX_LOW_SURROGATEThe maximum value of a Unicode low-surrogate code unit in the UTF-16 encoding, constant'\uDFFF'. A low-surrogate is also known as a trailing-surrogate.- Since:
- 1.5
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MIN_SURROGATE
public static final char MIN_SURROGATEThe minimum value of a Unicode surrogate code unit in the UTF-16 encoding, constant'\uD800'.- Since:
- 1.5
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MAX_SURROGATE
public static final char MAX_SURROGATEThe maximum value of a Unicode surrogate code unit in the UTF-16 encoding, constant'\uDFFF'.- Since:
- 1.5
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MIN_SUPPLEMENTARY_CODE_POINT
public static final int MIN_SUPPLEMENTARY_CODE_POINTThe minimum value of a Unicode supplementary code point, constantU+10000.- Since:
- 1.5
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MIN_CODE_POINT
public static final int MIN_CODE_POINTThe minimum value of a Unicode code point, constantU+0000.- Since:
- 1.5
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MAX_CODE_POINT
public static final int MAX_CODE_POINTThe maximum value of a Unicode code point, constantU+10FFFF.- Since:
- 1.5
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SIZE
public static final int SIZEThe number of bits used to represent acharvalue in unsigned binary form, constant16.- Since:
- 1.5
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BYTES
public static final int BYTESThe number of bytes used to represent acharvalue in unsigned binary form.- Since:
- 1.8
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Constructor Details
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Character
Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. The static factoryvalueOf(char)is generally a better choice, as it is likely to yield significantly better space and time performance.Constructs a newly allocatedCharacterobject that represents the specifiedcharvalue.- Parameters:
value- the value to be represented by theCharacterobject.
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Method Details
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describeConstable
Returns anOptionalcontaining the nominal descriptor for this instance.- Specified by:
describeConstablein interfaceConstable- Returns:
- an
Optionaldescribing the Character instance - Since:
- 15
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valueOf
Returns aCharacterinstance representing the specifiedcharvalue. If a newCharacterinstance is not required, this method should generally be used in preference to the constructorCharacter(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.- Parameters:
c- a char value.- Returns:
- a
Characterinstance representingc. - Since:
- 1.5
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charValue
public char charValue()Returns the value of thisCharacterobject.- Returns:
- the primitive
charvalue represented by this object.
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hashCode
public int hashCode()Returns a hash code for thisCharacter; equal to the result of invokingcharValue(). -
hashCode
public static int hashCode(char value) Returns a hash code for acharvalue; compatible withCharacter.hashCode().- Parameters:
value- Thecharfor which to return a hash code.- Returns:
- a hash code value for a
charvalue. - Since:
- 1.8
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equals
Compares this object against the specified object. The result istrueif and only if the argument is notnulland is aCharacterobject that represents the samecharvalue as this object. -
toString
Returns aStringobject representing thisCharacter's value. The result is a string of length 1 whose sole component is the primitivecharvalue represented by thisCharacterobject. -
toString
Returns aStringobject representing the specifiedchar. The result is a string of length 1 consisting solely of the specifiedchar.- API Note:
- This method cannot handle supplementary characters. To support
all Unicode characters, including supplementary characters, use
the
toString(int)method. - Parameters:
c- thecharto be converted- Returns:
- the string representation of the specified
char - Since:
- 1.4
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toString
Returns aStringobject representing the specified character (Unicode code point). The result is a string of length 1 or 2, consisting solely of the specifiedcodePoint.- Parameters:
codePoint- thecodePointto be converted- Returns:
- the string representation of the specified
codePoint - Throws:
IllegalArgumentException- if the specifiedcodePointis not a valid Unicode code point.- Since:
- 11
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isValidCodePoint
public static boolean isValidCodePoint(int codePoint) Determines whether the specified code point is a valid Unicode code point value.- Parameters:
codePoint- the Unicode code point to be tested- Returns:
trueif the specified code point value is betweenMIN_CODE_POINTandMAX_CODE_POINTinclusive;falseotherwise.- Since:
- 1.5
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isBmpCodePoint
public static boolean isBmpCodePoint(int codePoint) Determines whether the specified character (Unicode code point) is in the Basic Multilingual Plane (BMP). Such code points can be represented using a singlechar. -
isSupplementaryCodePoint
public static boolean isSupplementaryCodePoint(int codePoint) Determines whether the specified character (Unicode code point) is in the supplementary character range.- Parameters:
codePoint- the character (Unicode code point) to be tested- Returns:
trueif the specified code point is betweenMIN_SUPPLEMENTARY_CODE_POINTandMAX_CODE_POINTinclusive;falseotherwise.- Since:
- 1.5
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isHighSurrogate
public static boolean isHighSurrogate(char ch) Determines if the givencharvalue is a Unicode high-surrogate code unit (also known as leading-surrogate code unit).Such values do not represent characters by themselves, but are used in the representation of supplementary characters in the UTF-16 encoding.
- Parameters:
ch- thecharvalue to be tested.- Returns:
trueif thecharvalue is betweenMIN_HIGH_SURROGATEandMAX_HIGH_SURROGATEinclusive;falseotherwise.- Since:
- 1.5
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isLowSurrogate
public static boolean isLowSurrogate(char ch) Determines if the givencharvalue is a Unicode low-surrogate code unit (also known as trailing-surrogate code unit).Such values do not represent characters by themselves, but are used in the representation of supplementary characters in the UTF-16 encoding.
- Parameters:
ch- thecharvalue to be tested.- Returns:
trueif thecharvalue is betweenMIN_LOW_SURROGATEandMAX_LOW_SURROGATEinclusive;falseotherwise.- Since:
- 1.5
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isSurrogate
public static boolean isSurrogate(char ch) Determines if the givencharvalue is a Unicode surrogate code unit.Such values do not represent characters by themselves, but are used in the representation of supplementary characters in the UTF-16 encoding.
A char value is a surrogate code unit if and only if it is either a low-surrogate code unit or a high-surrogate code unit.
- Parameters:
ch- thecharvalue to be tested.- Returns:
trueif thecharvalue is betweenMIN_SURROGATEandMAX_SURROGATEinclusive;falseotherwise.- Since:
- 1.7
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isSurrogatePair
public static boolean isSurrogatePair(char high, char low) Determines whether the specified pair ofcharvalues is a valid Unicode surrogate pair.This method is equivalent to the expression:
isHighSurrogate(high) && isLowSurrogate(low)- Parameters:
high- the high-surrogate code value to be testedlow- the low-surrogate code value to be tested- Returns:
trueif the specified high and low-surrogate code values represent a valid surrogate pair;falseotherwise.- Since:
- 1.5
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charCount
public static int charCount(int codePoint) Determines the number ofcharvalues 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 using
isValidCodePointif necessary.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
- 2 if the character is a valid supplementary character; 1 otherwise.
- Since:
- 1.5
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toCodePoint
public static int toCodePoint(char high, char low) Converts the specified surrogate pair to its supplementary code point value. This method does not validate the specified surrogate pair. The caller must validate it usingisSurrogatePairif necessary.- Parameters:
high- the high-surrogate code unitlow- the low-surrogate code unit- Returns:
- the supplementary code point composed from the specified surrogate pair.
- Since:
- 1.5
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codePointAt
Returns the code point at the given index of theCharSequence. If thecharvalue at the given index in theCharSequenceis in the high-surrogate range, the following index is less than the length of theCharSequence, and thecharvalue at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thecharvalue at the given index is returned.- Parameters:
seq- a sequence ofcharvalues (Unicode code units)index- the index to thecharvalues (Unicode code units) inseqto be converted- Returns:
- the Unicode code point at the given index
- Throws:
NullPointerException- ifseqis null.IndexOutOfBoundsException- if the valueindexis negative or not less thanseq.length().- Since:
- 1.5
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codePointAt
public static int codePointAt(char[] a, int index) Returns the code point at the given index of thechararray. If thecharvalue at the given index in thechararray is in the high-surrogate range, the following index is less than the length of thechararray, and thecharvalue at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thecharvalue at the given index is returned.- Parameters:
a- thechararrayindex- the index to thecharvalues (Unicode code units) in thechararray to be converted- Returns:
- the Unicode code point at the given index
- Throws:
NullPointerException- ifais null.IndexOutOfBoundsException- if the valueindexis negative or not less than the length of thechararray.- Since:
- 1.5
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codePointAt
public static int codePointAt(char[] a, int index, int limit) Returns the code point at the given index of thechararray, where only array elements withindexless thanlimitcan be used. If thecharvalue at the given index in thechararray is in the high-surrogate range, the following index is less than thelimit, and thecharvalue at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thecharvalue at the given index is returned.- Parameters:
a- thechararrayindex- the index to thecharvalues (Unicode code units) in thechararray to be convertedlimit- the index after the last array element that can be used in thechararray- Returns:
- the Unicode code point at the given index
- Throws:
NullPointerException- ifais null.IndexOutOfBoundsException- if theindexargument is negative or not less than thelimitargument, or if thelimitargument is negative or greater than the length of thechararray.- Since:
- 1.5
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codePointBefore
Returns the code point preceding the given index of theCharSequence. If thecharvalue at(index - 1)in theCharSequenceis in the low-surrogate range,(index - 2)is not negative, and thecharvalue at(index - 2)in theCharSequenceis in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thecharvalue at(index - 1)is returned.- Parameters:
seq- theCharSequenceinstanceindex- the index following the code point that should be returned- Returns:
- the Unicode code point value before the given index.
- Throws:
NullPointerException- ifseqis null.IndexOutOfBoundsException- if theindexargument is less than 1 or greater thanseq.length().- Since:
- 1.5
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codePointBefore
public static int codePointBefore(char[] a, int index) Returns the code point preceding the given index of thechararray. If thecharvalue at(index - 1)in thechararray is in the low-surrogate range,(index - 2)is not negative, and thecharvalue at(index - 2)in thechararray is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thecharvalue at(index - 1)is returned.- Parameters:
a- thechararrayindex- the index following the code point that should be returned- Returns:
- the Unicode code point value before the given index.
- Throws:
NullPointerException- ifais null.IndexOutOfBoundsException- if theindexargument is less than 1 or greater than the length of thechararray- Since:
- 1.5
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codePointBefore
public static int codePointBefore(char[] a, int index, int start) Returns the code point preceding the given index of thechararray, where only array elements withindexgreater than or equal tostartcan be used. If thecharvalue at(index - 1)in thechararray is in the low-surrogate range,(index - 2)is not less thanstart, and thecharvalue at(index - 2)in thechararray is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, thecharvalue at(index - 1)is returned.- Parameters:
a- thechararrayindex- the index following the code point that should be returnedstart- the index of the first array element in thechararray- Returns:
- the Unicode code point value before the given index.
- Throws:
NullPointerException- ifais null.IndexOutOfBoundsException- if theindexargument is not greater than thestartargument or is greater than the length of thechararray, or if thestartargument is negative or not less than the length of thechararray.- Since:
- 1.5
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highSurrogate
public 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. If the specified character is not a supplementary character, an unspecifiedcharis returned.If
isSupplementaryCodePoint(x)istrue, thenisHighSurrogate(highSurrogate(x))andtoCodePoint(highSurrogate(x),lowSurrogate(x)) == xare also alwaystrue.- Parameters:
codePoint- a supplementary character (Unicode code point)- Returns:
- the leading surrogate code unit used to represent the character in the UTF-16 encoding
- Since:
- 1.7
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lowSurrogate
public 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. If the specified character is not a supplementary character, an unspecifiedcharis returned.If
isSupplementaryCodePoint(x)istrue, thenisLowSurrogate(lowSurrogate(x))andtoCodePoint(highSurrogate(x), lowSurrogate(x)) == xare also alwaystrue.- Parameters:
codePoint- a supplementary character (Unicode code point)- Returns:
- the trailing surrogate code unit used to represent the character in the UTF-16 encoding
- Since:
- 1.7
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toChars
public static int toChars(int codePoint, char[] dst, int dstIndex) Converts the specified character (Unicode code point) to its UTF-16 representation. If the specified code point is a BMP (Basic Multilingual Plane or Plane 0) value, the same value is stored indst[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.- Parameters:
codePoint- the character (Unicode code point) to be converted.dst- an array ofcharin which thecodePoint's UTF-16 value is stored.dstIndex- the start index into thedstarray where the converted value is stored.- Returns:
- 1 if the code point is a BMP code point, 2 if the code point is a supplementary code point.
- Throws:
IllegalArgumentException- if the specifiedcodePointis not a valid Unicode code point.NullPointerException- if the specifieddstis null.IndexOutOfBoundsException- ifdstIndexis negative or not less thandst.length, or ifdstatdstIndexdoesn't have enough array element(s) to store the resultingcharvalue(s). (IfdstIndexis equal todst.length-1and the specifiedcodePointis a supplementary character, the high-surrogate value is not stored indst[dstIndex].)- Since:
- 1.5
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toChars
public static char[] toChars(int codePoint) Converts the specified character (Unicode code point) to its UTF-16 representation stored in achararray. If the specified code point is a BMP (Basic Multilingual Plane or Plane 0) value, the resultingchararray has the same value ascodePoint. If the specified code point is a supplementary code point, the resultingchararray has the corresponding surrogate pair.- Parameters:
codePoint- a Unicode code point- Returns:
- a
chararray havingcodePoint's UTF-16 representation. - Throws:
IllegalArgumentException- if the specifiedcodePointis not a valid Unicode code point.- Since:
- 1.5
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codePointCount
Returns the number of Unicode code points in the text range of the specified char sequence. The text range begins at the specifiedbeginIndexand extends to thecharat indexendIndex - 1. Thus the length (inchars) of the text range isendIndex-beginIndex. Unpaired surrogates within the text range count as one code point each.- Parameters:
seq- the char sequencebeginIndex- the index to the firstcharof the text range.endIndex- the index after the lastcharof the text range.- Returns:
- the number of Unicode code points in the specified text range
- Throws:
NullPointerException- ifseqis null.IndexOutOfBoundsException- if thebeginIndexis negative, orendIndexis larger than the length of the given sequence, orbeginIndexis larger thanendIndex.- Since:
- 1.5
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codePointCount
public static int codePointCount(char[] a, int offset, int count) Returns the number of Unicode code points in a subarray of thechararray argument. Theoffsetargument is the index of the firstcharof the subarray and thecountargument specifies the length of the subarray inchars. Unpaired surrogates within the subarray count as one code point each.- Parameters:
a- thechararrayoffset- the index of the firstcharin the givenchararraycount- the length of the subarray inchars- Returns:
- the number of Unicode code points in the specified subarray
- Throws:
NullPointerException- ifais null.IndexOutOfBoundsException- ifoffsetorcountis negative, or ifoffset + countis larger than the length of the given array.- Since:
- 1.5
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offsetByCodePoints
Returns the index within the given char sequence that is offset from the givenindexbycodePointOffsetcode points. Unpaired surrogates within the text range given byindexandcodePointOffsetcount as one code point each.- Parameters:
seq- the char sequenceindex- the index to be offsetcodePointOffset- the offset in code points- Returns:
- the index within the char sequence
- Throws:
NullPointerException- ifseqis null.IndexOutOfBoundsException- ifindexis negative or larger then the length of the char sequence, or ifcodePointOffsetis positive and the subsequence starting withindexhas fewer thancodePointOffsetcode points, or ifcodePointOffsetis negative and the subsequence beforeindexhas fewer than the absolute value ofcodePointOffsetcode points.- Since:
- 1.5
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offsetByCodePoints
public static int offsetByCodePoints(char[] a, int start, int count, int index, int codePointOffset) Returns the index within the givencharsubarray that is offset from the givenindexbycodePointOffsetcode points. Thestartandcountarguments specify a subarray of thechararray. Unpaired surrogates within the text range given byindexandcodePointOffsetcount as one code point each.- Parameters:
a- thechararraystart- the index of the firstcharof the subarraycount- the length of the subarray incharsindex- the index to be offsetcodePointOffset- the offset in code points- Returns:
- the index within the subarray
- Throws:
NullPointerException- ifais null.IndexOutOfBoundsException- ifstartorcountis negative, or ifstart + countis larger than the length of the given array, or ifindexis less thanstartor larger thenstart + count, or ifcodePointOffsetis positive and the text range starting withindexand ending withstart + count - 1has fewer thancodePointOffsetcode points, or ifcodePointOffsetis negative and the text range starting withstartand ending withindex - 1has fewer than the absolute value ofcodePointOffsetcode points.- Since:
- 1.5
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isLowerCase
public static boolean isLowerCase(char ch) Determines if the specified character is a lowercase character.A character is lowercase if its general category type, provided by
Character.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 the
isLowerCase(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is lowercase;falseotherwise.- See Also:
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isLowerCase
public static boolean isLowerCase(int codePoint) Determines if the specified character (Unicode code point) is a lowercase character.A character is lowercase if its general category type, provided by
getType(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.
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is lowercase;falseotherwise.- Since:
- 1.5
- See Also:
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isUpperCase
public static boolean isUpperCase(char ch) Determines if the specified character is an uppercase character.A character is uppercase if its general category type, provided by
Character.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 the
isUpperCase(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is uppercase;falseotherwise.- Since:
- 1.0
- See Also:
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isUpperCase
public static boolean isUpperCase(int codePoint) Determines if the specified character (Unicode code point) is an uppercase character.A character is uppercase if its general category type, provided by
getType(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.
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is uppercase;falseotherwise.- Since:
- 1.5
- See Also:
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isTitleCase
public static boolean isTitleCase(char ch) Determines if the specified character is a titlecase character.A character is a titlecase character if its general category type, provided by
Character.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 returns
true: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 Z
Many other Unicode characters are titlecase too.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isTitleCase(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is titlecase;falseotherwise.- Since:
- 1.0.2
- See Also:
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isTitleCase
public static boolean isTitleCase(int codePoint) Determines if the specified character (Unicode code point) is a titlecase character.A character is a titlecase character if its general category type, provided by
getType(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 returns
true: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 Z
Many other Unicode characters are titlecase too.
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is titlecase;falseotherwise.- Since:
- 1.5
- See Also:
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isDigit
public static boolean isDigit(char ch) Determines if the specified character is a digit.A character is a digit if its general category type, provided by
Character.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 digits
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isDigit(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is a digit;falseotherwise.- See Also:
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isDigit
public static boolean isDigit(int codePoint) Determines if the specified character (Unicode code point) is a digit.A character is a digit if its general category type, provided by
getType(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 digits
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a digit;falseotherwise.- Since:
- 1.5
- See Also:
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isDefined
public static boolean isDefined(char ch) Determines if a character is defined in Unicode.A character is defined if at least one of the following is true:
- It has an entry in the UnicodeData file.
- It has a value in a range defined by the UnicodeData file.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isDefined(int)method.- Parameters:
ch- the character to be tested- Returns:
trueif the character has a defined meaning in Unicode;falseotherwise.- Since:
- 1.0.2
- See Also:
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isDefined
public static boolean isDefined(int codePoint) Determines if a character (Unicode code point) is defined in Unicode.A character is defined if at least one of the following is true:
- It has an entry in the UnicodeData file.
- It has a value in a range defined by the UnicodeData file.
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character has a defined meaning in Unicode;falseotherwise.- Since:
- 1.5
- See Also:
-
isLetter
public static boolean isLetter(char ch) Determines if the specified character is a letter.A character is considered to be a letter if its general category type, provided by
Character.getType(ch), is any of the following:-
UPPERCASE_LETTER -
LOWERCASE_LETTER -
TITLECASE_LETTER -
MODIFIER_LETTER -
OTHER_LETTER
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isLetter(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is a letter;falseotherwise.- See Also:
-
-
isLetter
public static boolean isLetter(int codePoint) Determines if the specified character (Unicode code point) is a letter.A character is considered to be a letter if its general category type, provided by
getType(codePoint), is any of the following:-
UPPERCASE_LETTER -
LOWERCASE_LETTER -
TITLECASE_LETTER -
MODIFIER_LETTER -
OTHER_LETTER
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a letter;falseotherwise.- Since:
- 1.5
- See Also:
-
-
isLetterOrDigit
public static boolean isLetterOrDigit(char ch) Determines if the specified character is a letter or digit.A character is considered to be a letter or digit if either
Character.isLetter(char ch)orCharacter.isDigit(char ch)returnstruefor the character.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isLetterOrDigit(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is a letter or digit;falseotherwise.- Since:
- 1.0.2
- See Also:
-
isLetterOrDigit
public static boolean isLetterOrDigit(int codePoint) Determines if the specified character (Unicode code point) is a letter or digit.A character is considered to be a letter or digit if either
isLetter(codePoint)orisDigit(codePoint)returnstruefor the character.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a letter or digit;falseotherwise.- Since:
- 1.5
- See Also:
-
isJavaLetter
Deprecated.Replaced by isJavaIdentifierStart(char).Determines if the specified character is permissible as the first character in a Java identifier.A character may start a Java identifier if and only if one of the following conditions is true:
-
isLetter(ch)returnstrue -
getType(ch)returnsLETTER_NUMBER -
chis a currency symbol (such as'$') -
chis a connecting punctuation character (such as'_').
- Parameters:
ch- the character to be tested.- Returns:
trueif the character may start a Java identifier;falseotherwise.- Since:
- 1.0.2
- See Also:
-
-
isJavaLetterOrDigit
Deprecated.Replaced by isJavaIdentifierPart(char).Determines if the specified character may be part of a Java identifier as other than the first character.A character may be part of a Java identifier if and only if one of the following conditions is true:
- it is a letter
- it is a currency symbol (such as
'$') - it is a connecting punctuation character (such as
'_') - it is a digit
- it is a numeric letter (such as a Roman numeral character)
- it is a combining mark
- it is a non-spacing mark
-
isIdentifierIgnorablereturnstruefor the character.
- Parameters:
ch- the character to be tested.- Returns:
trueif the character may be part of a Java identifier;falseotherwise.- Since:
- 1.0.2
- See Also:
-
isAlphabetic
public static boolean isAlphabetic(int codePoint) Determines if the specified character (Unicode code point) is alphabetic.A character is considered to be alphabetic if its general category type, provided by
getType(codePoint), is any of the following:-
UPPERCASE_LETTER -
LOWERCASE_LETTER -
TITLECASE_LETTER -
MODIFIER_LETTER -
OTHER_LETTER -
LETTER_NUMBER
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a Unicode alphabet character,falseotherwise.- Since:
- 1.7
-
-
isIdeographic
public 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.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a Unicode ideograph character,falseotherwise.- Since:
- 1.7
-
isJavaIdentifierStart
public static boolean isJavaIdentifierStart(char ch) Determines if the specified character is permissible as the first character in a Java identifier.A character may start a Java identifier if and only if one of the following conditions is true:
-
isLetter(ch)returnstrue -
getType(ch)returnsLETTER_NUMBER -
chis a currency symbol (such as'$') -
chis a connecting punctuation character (such as'_').
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isJavaIdentifierStart(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character may start a Java identifier;falseotherwise.- Since:
- 1.1
- See Also:
-
-
isJavaIdentifierStart
public static boolean isJavaIdentifierStart(int codePoint) Determines if the character (Unicode code point) is permissible as the first character in a Java identifier.A character may start a Java identifier if and only if one of the following conditions is true:
-
isLetter(codePoint)returnstrue -
getType(codePoint)returnsLETTER_NUMBER - the referenced character is a currency symbol (such as
'$') - the referenced character is a connecting punctuation character
(such as
'_').
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character may start a Java identifier;falseotherwise.- Since:
- 1.5
- See Also:
-
-
isJavaIdentifierPart
public static boolean isJavaIdentifierPart(char ch) Determines if the specified character may be part of a Java identifier as other than the first character.A character may be part of a Java identifier if any of the following conditions are true:
- it is a letter
- it is a currency symbol (such as
'$') - it is a connecting punctuation character (such as
'_') - it is a digit
- it is a numeric letter (such as a Roman numeral character)
- it is a combining mark
- it is a non-spacing mark
-
isIdentifierIgnorablereturnstruefor the character
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isJavaIdentifierPart(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character may be part of a Java identifier;falseotherwise.- Since:
- 1.1
- See Also:
-
isJavaIdentifierPart
public static boolean isJavaIdentifierPart(int codePoint) Determines if the character (Unicode code point) may be part of a Java identifier as other than the first character.A character may be part of a Java identifier if any of the following conditions are true:
- it is a letter
- it is a currency symbol (such as
'$') - it is a connecting punctuation character (such as
'_') - it is a digit
- it is a numeric letter (such as a Roman numeral character)
- it is a combining mark
- it is a non-spacing mark
-
isIdentifierIgnorable(codePoint)returnstruefor the code point
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character may be part of a Java identifier;falseotherwise.- Since:
- 1.5
- See Also:
-
isUnicodeIdentifierStart
public static boolean isUnicodeIdentifierStart(char ch) Determines if the specified character is permissible as the first character in a Unicode identifier.A character may start a Unicode identifier if and only if one of the following conditions is true:
-
isLetter(ch)returnstrue -
getType(ch)returnsLETTER_NUMBER. - it is an
Other_ID_Startcharacter.
This method conforms to UAX31-R1: Default Identifiers requirement of the Unicode Standard, with the following profile of UAX31:
Start := ID_Start + 'VERTICAL TILDE' (U+2E2F)
'VERTICAL TILDE'is added toStartfor backward compatibility.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isUnicodeIdentifierStart(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character may start a Unicode identifier;falseotherwise.- Since:
- 1.1
- See Also:
-
-
isUnicodeIdentifierStart
public static boolean isUnicodeIdentifierStart(int codePoint) Determines if the specified character (Unicode code point) is permissible as the first character in a Unicode identifier.A character may start a Unicode identifier if and only if one of the following conditions is true:
-
isLetter(codePoint)returnstrue -
getType(codePoint)returnsLETTER_NUMBER. - it is an
Other_ID_Startcharacter.
This method conforms to UAX31-R1: Default Identifiers requirement of the Unicode Standard, with the following profile of UAX31:
Start := ID_Start + 'VERTICAL TILDE' (U+2E2F)
'VERTICAL TILDE'is added toStartfor backward compatibility.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character may start a Unicode identifier;falseotherwise.- Since:
- 1.5
- See Also:
-
-
isUnicodeIdentifierPart
public static boolean isUnicodeIdentifierPart(char ch) Determines if the specified character may be part of a Unicode identifier as other than the first character.A character may be part of a Unicode identifier if and only if one of the following statements is true:
- it is a letter
- it is a connecting punctuation character (such as
'_') - it is a digit
- it is a numeric letter (such as a Roman numeral character)
- it is a combining mark
- it is a non-spacing mark
-
isIdentifierIgnorablereturnstruefor this character. - it is an
Other_ID_Startcharacter. - it is an
Other_ID_Continuecharacter.
This method conforms to UAX31-R1: Default Identifiers requirement of the Unicode Standard, with the following profile of UAX31:
Continue := Start + ID_Continue + ignorable Medial := empty ignorable := isIdentifierIgnorable(char) returns true for the character
ignorableis added toContinuefor backward compatibility.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isUnicodeIdentifierPart(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character may be part of a Unicode identifier;falseotherwise.- Since:
- 1.1
- See Also:
-
isUnicodeIdentifierPart
public 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.A character may be part of a Unicode identifier if and only if one of the following statements is true:
- it is a letter
- it is a connecting punctuation character (such as
'_') - it is a digit
- it is a numeric letter (such as a Roman numeral character)
- it is a combining mark
- it is a non-spacing mark
-
isIdentifierIgnorablereturnstruefor this character. - it is an
Other_ID_Startcharacter. - it is an
Other_ID_Continuecharacter.
This method conforms to UAX31-R1: Default Identifiers requirement of the Unicode Standard, with the following profile of UAX31:
Continue := Start + ID_Continue + ignorable Medial := empty ignorable := isIdentifierIgnorable(int) returns true for the character
ignorableis added toContinuefor backward compatibility.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character may be part of a Unicode identifier;falseotherwise.- Since:
- 1.5
- See Also:
-
isIdentifierIgnorable
public 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.The following Unicode characters are ignorable in a Java identifier or a Unicode identifier:
- ISO control characters that are not whitespace
'\u0000'through'\u0008''\u000E'through'\u001B''\u007F'through'\u009F'
- all characters that have the
FORMATgeneral category value
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isIdentifierIgnorable(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is an ignorable control character that may be part of a Java or Unicode identifier;falseotherwise.- Since:
- 1.1
- See Also:
- ISO control characters that are not whitespace
-
isIdentifierIgnorable
public 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.The following Unicode characters are ignorable in a Java identifier or a Unicode identifier:
- ISO control characters that are not whitespace
'\u0000'through'\u0008''\u000E'through'\u001B''\u007F'through'\u009F'
- all characters that have the
FORMATgeneral category value
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is an ignorable control character that may be part of a Java or Unicode identifier;falseotherwise.- Since:
- 1.5
- See Also:
- ISO control characters that are not whitespace
-
toLowerCase
public static char toLowerCase(char ch) Converts the character argument to lowercase using case mapping information from the UnicodeData file.Note that
Character.isLowerCase(Character.toLowerCase(ch))does not always returntruefor some ranges of characters, particularly those that are symbols or ideographs.In general,
String.toLowerCase()should be used to map characters to lowercase.Stringcase mapping methods have several benefits overCharactercase mapping methods.Stringcase mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharactercase mapping methods cannot.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
toLowerCase(int)method.- Parameters:
ch- the character to be converted.- Returns:
- the lowercase equivalent of the character, if any; otherwise, the character itself.
- See Also:
-
toLowerCase
public static int toLowerCase(int codePoint) Converts the character (Unicode code point) argument to lowercase using case mapping information from the UnicodeData file.Note that
Character.isLowerCase(Character.toLowerCase(codePoint))does not always returntruefor some ranges of characters, particularly those that are symbols or ideographs.In general,
String.toLowerCase()should be used to map characters to lowercase.Stringcase mapping methods have several benefits overCharactercase mapping methods.Stringcase mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharactercase mapping methods cannot.- Parameters:
codePoint- the character (Unicode code point) to be converted.- Returns:
- the lowercase equivalent of the character (Unicode code point), if any; otherwise, the character itself.
- Since:
- 1.5
- See Also:
-
toUpperCase
public static char toUpperCase(char ch) Converts the character argument to uppercase using case mapping information from the UnicodeData file.Note that
Character.isUpperCase(Character.toUpperCase(ch))does not always returntruefor some ranges of characters, particularly those that are symbols or ideographs.In general,
String.toUpperCase()should be used to map characters to uppercase.Stringcase mapping methods have several benefits overCharactercase mapping methods.Stringcase mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharactercase mapping methods cannot.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
toUpperCase(int)method.- Parameters:
ch- the character to be converted.- Returns:
- the uppercase equivalent of the character, if any; otherwise, the character itself.
- See Also:
-
toUpperCase
public static int toUpperCase(int codePoint) Converts the character (Unicode code point) argument to uppercase using case mapping information from the UnicodeData file.Note that
Character.isUpperCase(Character.toUpperCase(codePoint))does not always returntruefor some ranges of characters, particularly those that are symbols or ideographs.In general,
String.toUpperCase()should be used to map characters to uppercase.Stringcase mapping methods have several benefits overCharactercase mapping methods.Stringcase mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas theCharactercase mapping methods cannot.- Parameters:
codePoint- the character (Unicode code point) to be converted.- Returns:
- the uppercase equivalent of the character, if any; otherwise, the character itself.
- Since:
- 1.5
- See Also:
-
toTitleCase
public static char toTitleCase(char ch) Converts the character argument to titlecase using case mapping information from the UnicodeData file. If a character has no explicit titlecase mapping and is not itself a titlecase char according to UnicodeData, then the uppercase mapping is returned as an equivalent titlecase mapping. If thecharargument is already a titlecasechar, the samecharvalue will be returned.Note that
Character.isTitleCase(Character.toTitleCase(ch))does not always returntruefor some ranges of characters.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
toTitleCase(int)method.- Parameters:
ch- the character to be converted.- Returns:
- the titlecase equivalent of the character, if any; otherwise, the character itself.
- Since:
- 1.0.2
- See Also:
-
toTitleCase
public static int toTitleCase(int codePoint) Converts the character (Unicode code point) argument to titlecase using case mapping information from the UnicodeData file. If a character has no explicit titlecase mapping and is not itself a titlecase char according to UnicodeData, then the uppercase mapping is returned as an equivalent titlecase mapping. If the character argument is already a titlecase character, the same character value will be returned.Note that
Character.isTitleCase(Character.toTitleCase(codePoint))does not always returntruefor some ranges of characters.- Parameters:
codePoint- the character (Unicode code point) to be converted.- Returns:
- the titlecase equivalent of the character, if any; otherwise, the character itself.
- Since:
- 1.5
- See Also:
-
digit
public static int digit(char ch, int radix) Returns the numeric value of the characterchin the specified radix.If the radix is not in the range
MIN_RADIX≤radix≤MAX_RADIXor if the value ofchis not a valid digit in the specified radix,-1is returned. A character is a valid digit if at least one of the following is true:- The method
isDigitistrueof 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. - The character is one of the uppercase Latin letters
'A'through'Z'and its code is less thanradix + 'A' - 10. In this case,ch - 'A' + 10is returned. - The character is one of the lowercase Latin letters
'a'through'z'and its code is less thanradix + 'a' - 10. In this case,ch - 'a' + 10is returned. - The character is one of the fullwidth uppercase Latin letters A
(
'\uFF21') through Z ('\uFF3A') and its code is less thanradix + '\uFF21' - 10. In this case,ch - '\uFF21' + 10is returned. - The character is one of the fullwidth lowercase Latin letters a
(
'\uFF41') through z ('\uFF5A') and its code is less thanradix + '\uFF41' - 10. In this case,ch - '\uFF41' + 10is returned.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
digit(int, int)method.- Parameters:
ch- the character to be converted.radix- the radix.- Returns:
- the numeric value represented by the character in the specified radix.
- See Also:
- The method
-
digit
public static int digit(int codePoint, int radix) Returns the numeric value of the specified character (Unicode code point) in the specified radix.If the radix is not in the range
MIN_RADIX≤radix≤MAX_RADIXor if the character is not a valid digit in the specified radix,-1is returned. A character is a valid digit if at least one of the following is true:- The method
isDigit(codePoint)istrueof 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. - The character is one of the uppercase Latin letters
'A'through'Z'and its code is less thanradix + 'A' - 10. In this case,codePoint - 'A' + 10is returned. - The character is one of the lowercase Latin letters
'a'through'z'and its code is less thanradix + 'a' - 10. In this case,codePoint - 'a' + 10is returned. - The character is one of the fullwidth uppercase Latin letters A
(
'\uFF21') through Z ('\uFF3A') and its code is less thanradix + '\uFF21' - 10. In this case,codePoint - '\uFF21' + 10is returned. - The character is one of the fullwidth lowercase Latin letters a
(
'\uFF41') through z ('\uFF5A') and its code is less thanradix + '\uFF41'- 10. In this case,codePoint - '\uFF41' + 10is returned.
- Parameters:
codePoint- the character (Unicode code point) to be converted.radix- the radix.- Returns:
- the numeric value represented by the character in the specified radix.
- Since:
- 1.5
- See Also:
- The method
-
getNumericValue
public static int getNumericValue(char ch) Returns theintvalue 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 thesecharvalues.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 the
getNumericValue(int)method.- Parameters:
ch- the character to be converted.- Returns:
- the numeric value of the character, as a nonnegative
intvalue; -2 if the character has a numeric value but the value can not be represented as a nonnegativeintvalue; -1 if the character has no numeric value. - Since:
- 1.1
- See Also:
-
getNumericValue
public static int getNumericValue(int codePoint) Returns theintvalue that the specified character (Unicode code point) represents. For example, the character'\u216C'(the Roman numeral fifty) will return anintwith 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 thesecharvalues.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.
- Parameters:
codePoint- the character (Unicode code point) to be converted.- Returns:
- the numeric value of the character, as a nonnegative
intvalue; -2 if the character has a numeric value but the value can not be represented as a nonnegativeintvalue; -1 if the character has no numeric value. - Since:
- 1.5
- See Also:
-
isSpace
Deprecated.Replaced by isWhitespace(char).Determines if the specified character is ISO-LATIN-1 white space. This method returnstruefor the following five characters only:Character Code Name '\t'U+0009HORIZONTAL TABULATION'\n'U+000ANEW LINE'\f'U+000CFORM FEED'\r'U+000DCARRIAGE RETURN' 'U+0020SPACE- Parameters:
ch- the character to be tested.- Returns:
trueif the character is ISO-LATIN-1 white space;falseotherwise.- See Also:
-
isSpaceChar
public static boolean isSpaceChar(char ch) Determines if the specified character is a Unicode space character. A character is considered to be a space character if and only if it is specified to be a space character by the Unicode Standard. This method returns true if the character's general category type is any of the following:-
SPACE_SEPARATOR -
LINE_SEPARATOR -
PARAGRAPH_SEPARATOR
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isSpaceChar(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is a space character;falseotherwise.- Since:
- 1.1
- See Also:
-
-
isSpaceChar
public static boolean isSpaceChar(int codePoint) Determines if the specified character (Unicode code point) is a Unicode space character. A character is considered to be a space character if and only if it is specified to be a space character by the Unicode Standard. This method returns true if the character's general category type is any of the following:- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a space character;falseotherwise.- Since:
- 1.5
- See Also:
-
isWhitespace
public static boolean isWhitespace(char ch) Determines if the specified character is white space according to Java. A character is a Java whitespace character if and only if it satisfies one of the following criteria:- It is a Unicode space character (
SPACE_SEPARATOR,LINE_SEPARATOR, orPARAGRAPH_SEPARATOR) but is not also a non-breaking space ('\u00A0','\u2007','\u202F'). - It is
'\t', U+0009 HORIZONTAL TABULATION. - It is
'\n', U+000A LINE FEED. - It is
'\u000B', U+000B VERTICAL TABULATION. - It is
'\f', U+000C FORM FEED. - It is
'\r', U+000D CARRIAGE RETURN. - It is
'\u001C', U+001C FILE SEPARATOR. - It is
'\u001D', U+001D GROUP SEPARATOR. - It is
'\u001E', U+001E RECORD SEPARATOR. - It is
'\u001F', U+001F UNIT SEPARATOR.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
isWhitespace(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is a Java whitespace character;falseotherwise.- Since:
- 1.1
- See Also:
- It is a Unicode space character (
-
isWhitespace
public static boolean isWhitespace(int codePoint) Determines if the specified character (Unicode code point) is white space according to Java. A character is a Java whitespace character if and only if it satisfies one of the following criteria:- It is a Unicode space character (
SPACE_SEPARATOR,LINE_SEPARATOR, orPARAGRAPH_SEPARATOR) but is not also a non-breaking space ('\u00A0','\u2007','\u202F'). - It is
'\t', U+0009 HORIZONTAL TABULATION. - It is
'\n', U+000A LINE FEED. - It is
'\u000B', U+000B VERTICAL TABULATION. - It is
'\f', U+000C FORM FEED. - It is
'\r', U+000D CARRIAGE RETURN. - It is
'\u001C', U+001C FILE SEPARATOR. - It is
'\u001D', U+001D GROUP SEPARATOR. - It is
'\u001E', U+001E RECORD SEPARATOR. - It is
'\u001F', U+001F UNIT SEPARATOR.
- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is a Java whitespace character;falseotherwise.- Since:
- 1.5
- See Also:
- It is a Unicode space character (
-
isISOControl
public static boolean isISOControl(char ch) Determines if the specified character is an ISO control character. A character is considered to be an ISO control character if its code is in the range'\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 the
isISOControl(int)method.- Parameters:
ch- the character to be tested.- Returns:
trueif the character is an ISO control character;falseotherwise.- Since:
- 1.1
- See Also:
-
isISOControl
public static boolean isISOControl(int codePoint) Determines if the referenced character (Unicode code point) is an ISO control character. A character is considered to be an ISO control character if its code is in the range'\u0000'through'\u001F'or in the range'\u007F'through'\u009F'.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is an ISO control character;falseotherwise.- Since:
- 1.5
- See Also:
-
getType
public static int getType(char ch) Returns a value indicating a character's general category.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
getType(int)method.- Parameters:
ch- the character to be tested.- Returns:
- a value of type
intrepresenting the character's general category. - Since:
- 1.1
- See Also:
-
COMBINING_SPACING_MARKCONNECTOR_PUNCTUATIONCONTROLCURRENCY_SYMBOLDASH_PUNCTUATIONDECIMAL_DIGIT_NUMBERENCLOSING_MARKEND_PUNCTUATIONFINAL_QUOTE_PUNCTUATIONFORMATINITIAL_QUOTE_PUNCTUATIONLETTER_NUMBERLINE_SEPARATORLOWERCASE_LETTERMATH_SYMBOLMODIFIER_LETTERMODIFIER_SYMBOLNON_SPACING_MARKOTHER_LETTEROTHER_NUMBEROTHER_PUNCTUATIONOTHER_SYMBOLPARAGRAPH_SEPARATORPRIVATE_USESPACE_SEPARATORSTART_PUNCTUATIONSURROGATETITLECASE_LETTERUNASSIGNEDUPPERCASE_LETTER
-
getType
public static int getType(int codePoint) Returns a value indicating a character's general category.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
- a value of type
intrepresenting the character's general category. - Since:
- 1.5
- See Also:
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COMBINING_SPACING_MARKCONNECTOR_PUNCTUATIONCONTROLCURRENCY_SYMBOLDASH_PUNCTUATIONDECIMAL_DIGIT_NUMBERENCLOSING_MARKEND_PUNCTUATIONFINAL_QUOTE_PUNCTUATIONFORMATINITIAL_QUOTE_PUNCTUATIONLETTER_NUMBERLINE_SEPARATORLOWERCASE_LETTERMATH_SYMBOLMODIFIER_LETTERMODIFIER_SYMBOLNON_SPACING_MARKOTHER_LETTEROTHER_NUMBEROTHER_PUNCTUATIONOTHER_SYMBOLPARAGRAPH_SEPARATORPRIVATE_USESPACE_SEPARATORSTART_PUNCTUATIONSURROGATETITLECASE_LETTERUNASSIGNEDUPPERCASE_LETTER
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forDigit
public static char forDigit(int digit, int radix) Determines the character representation for a specific digit in the specified radix. If the value ofradixis not a valid radix, or the value ofdigitis not a valid digit in the specified radix, the null character ('\u0000') is returned.The
radixargument is valid if it is greater than or equal toMIN_RADIXand less than or equal toMAX_RADIX. Thedigitargument is valid if0 <= digit < radix.If the digit is less than 10, then
'0' + digitis returned. Otherwise, the value'a' + digit - 10is returned.- Parameters:
digit- the number to convert to a character.radix- the radix.- Returns:
- the
charrepresentation of the specified digit in the specified radix. - See Also:
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getDirectionality
public static byte getDirectionality(char ch) Returns the Unicode directionality property for the given character. Character directionality is used to calculate the visual ordering of text. The directionality value of undefinedcharvalues isDIRECTIONALITY_UNDEFINED.Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the
getDirectionality(int)method.- Parameters:
ch-charfor which the directionality property is requested.- Returns:
- the directionality property of the
charvalue. - Since:
- 1.4
- See Also:
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DIRECTIONALITY_UNDEFINEDDIRECTIONALITY_LEFT_TO_RIGHTDIRECTIONALITY_RIGHT_TO_LEFTDIRECTIONALITY_RIGHT_TO_LEFT_ARABICDIRECTIONALITY_EUROPEAN_NUMBERDIRECTIONALITY_EUROPEAN_NUMBER_SEPARATORDIRECTIONALITY_EUROPEAN_NUMBER_TERMINATORDIRECTIONALITY_ARABIC_NUMBERDIRECTIONALITY_COMMON_NUMBER_SEPARATORDIRECTIONALITY_NONSPACING_MARKDIRECTIONALITY_BOUNDARY_NEUTRALDIRECTIONALITY_PARAGRAPH_SEPARATORDIRECTIONALITY_SEGMENT_SEPARATORDIRECTIONALITY_WHITESPACEDIRECTIONALITY_OTHER_NEUTRALSDIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDINGDIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDEDIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDINGDIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDEDIRECTIONALITY_POP_DIRECTIONAL_FORMATDIRECTIONALITY_LEFT_TO_RIGHT_ISOLATEDIRECTIONALITY_RIGHT_TO_LEFT_ISOLATEDIRECTIONALITY_FIRST_STRONG_ISOLATEDIRECTIONALITY_POP_DIRECTIONAL_ISOLATE
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getDirectionality
public static byte getDirectionality(int codePoint) Returns the Unicode directionality property for the given character (Unicode code point). Character directionality is used to calculate the visual ordering of text. The directionality value of undefined character isDIRECTIONALITY_UNDEFINED.- Parameters:
codePoint- the character (Unicode code point) for which the directionality property is requested.- Returns:
- the directionality property of the character.
- Since:
- 1.5
- See Also:
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DIRECTIONALITY_UNDEFINEDDIRECTIONALITY_LEFT_TO_RIGHTDIRECTIONALITY_RIGHT_TO_LEFTDIRECTIONALITY_RIGHT_TO_LEFT_ARABICDIRECTIONALITY_EUROPEAN_NUMBERDIRECTIONALITY_EUROPEAN_NUMBER_SEPARATORDIRECTIONALITY_EUROPEAN_NUMBER_TERMINATORDIRECTIONALITY_ARABIC_NUMBERDIRECTIONALITY_COMMON_NUMBER_SEPARATORDIRECTIONALITY_NONSPACING_MARKDIRECTIONALITY_BOUNDARY_NEUTRALDIRECTIONALITY_PARAGRAPH_SEPARATORDIRECTIONALITY_SEGMENT_SEPARATORDIRECTIONALITY_WHITESPACEDIRECTIONALITY_OTHER_NEUTRALSDIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDINGDIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDEDIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDINGDIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDEDIRECTIONALITY_POP_DIRECTIONAL_FORMATDIRECTIONALITY_LEFT_TO_RIGHT_ISOLATEDIRECTIONALITY_RIGHT_TO_LEFT_ISOLATEDIRECTIONALITY_FIRST_STRONG_ISOLATEDIRECTIONALITY_POP_DIRECTIONAL_ISOLATE
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isMirrored
public static boolean isMirrored(char ch) Determines whether the character is mirrored according to the Unicode specification. Mirrored characters should have their glyphs horizontally mirrored when displayed in text that is right-to-left. For example,'\u0028'LEFT PARENTHESIS is semantically defined to be an opening 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 the
isMirrored(int)method.- Parameters:
ch-charfor which the mirrored property is requested- Returns:
trueif the char is mirrored,falseif thecharis not mirrored or is not defined.- Since:
- 1.4
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isMirrored
public static boolean isMirrored(int codePoint) Determines whether the specified character (Unicode code point) is mirrored according to the Unicode specification. Mirrored characters should have their glyphs horizontally mirrored when displayed in text that is right-to-left. For example,'\u0028'LEFT PARENTHESIS is semantically defined to be an opening parenthesis. This will appear as a "(" in text that is left-to-right but as a ")" in text that is right-to-left.- Parameters:
codePoint- the character (Unicode code point) to be tested.- Returns:
trueif the character is mirrored,falseif the character is not mirrored or is not defined.- Since:
- 1.5
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compareTo
Compares twoCharacterobjects numerically.- Specified by:
compareToin interfaceComparable<Character>- Parameters:
anotherCharacter- theCharacterto be compared.- Returns:
- the value
0if the argumentCharacteris equal to thisCharacter; a value less than0if thisCharacteris numerically less than theCharacterargument; and a value greater than0if thisCharacteris numerically greater than theCharacterargument (unsigned comparison). Note that this is strictly a numerical comparison; it is not locale-dependent. - Since:
- 1.2
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compare
public static int compare(char x, char y) Compares twocharvalues numerically. The value returned is identical to what would be returned by:Character.valueOf(x).compareTo(Character.valueOf(y))- Parameters:
x- the firstcharto comparey- the secondcharto compare- Returns:
- the value
0ifx == y; a value less than0ifx < y; and a value greater than0ifx > y - Since:
- 1.7
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reverseBytes
public static char reverseBytes(char ch) Returns the value obtained by reversing the order of the bytes in the specifiedcharvalue.- Parameters:
ch- Thecharof which to reverse the byte order.- Returns:
- the value obtained by reversing (or, equivalently, swapping)
the bytes in the specified
charvalue. - Since:
- 1.5
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getName
Returns the Unicode name of the specified charactercodePoint, or null if the code point isunassigned.Note: if the specified character is not assigned a name by the UnicodeData 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.ROOT);- Parameters:
codePoint- the character (Unicode code point)- Returns:
- the Unicode name of the specified character, or null if the code point is unassigned.
- Throws:
IllegalArgumentException- if the specifiedcodePointis not a valid Unicode code point.- Since:
- 1.7
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codePointOf
Returns the code point value of the Unicode character specified by the given Unicode character name.Note: if a character is not assigned a name by the UnicodeData file (part of the Unicode Character Database maintained by the Unicode Consortium), its name is defined as the result of expression:
Character.UnicodeBlock.of(codePoint).toString().replace('_', ' ') + " " + Integer.toHexString(codePoint).toUpperCase(Locale.ROOT);The
namematching is case insensitive, with any leading and trailing whitespace character removed.- Parameters:
name- the Unicode character name- Returns:
- the code point value of the character specified by its name.
- Throws:
IllegalArgumentException- if the specifiednameis not a valid Unicode character name.NullPointerException- ifnameisnull- Since:
- 9
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