Character (Java 2 Platform SE 5.0) (original) (raw)
java.lang
Class Character
java.lang.Object
java.lang.Character
All Implemented Interfaces:
Serializable, Comparable<Character>
public final class Character
extends Object
implements Serializable, Comparable<Character>
The Character
class wraps a value of the primitive type char
in an object. An object of typeCharacter
contains a single field whose type ischar
.
In addition, this class provides several methods for determining a character's category (lowercase letter, digit, etc.) and for converting characters from uppercase to lowercase and vice versa.
Character information is based on the Unicode Standard, version 4.0.
The methods and data of class Character
are defined by the information in the UnicodeData file that is part of the Unicode Character Database maintained by the Unicode Consortium. This file specifies various properties including name and general category for every defined Unicode code point or character range.
The file and its description are available from the Unicode Consortium at:
Unicode Character Representations
The char
data type (and therefore the value that aCharacter
object encapsulates) are based on the original Unicode specification, which defined characters as fixed-width 16-bit entities. The Unicode standard has since been changed to allow for characters whose representation requires more than 16 bits. The range of legal _code point_s 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 character_s. The Java 2 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. Anint
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
char
value cannot support supplementary characters. They treatchar
values from the surrogate ranges as undefined characters. For example,Character.isLetter('\uD840')
returnsfalse
, even though this specific value if followed by any low-surrogate value in a string would represent a letter. - The methods that accept an
int
value support all Unicode characters, including supplementary characters. For example,Character.isLetter(0x2F81A)
returnstrue
because the code point value represents a letter (a CJK ideograph).
In the J2SE 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-bitchar
values that are code units of the UTF-16 encoding. For more information on Unicode terminology, refer to theUnicode Glossary.
Since:
1.0
See Also:
Nested Class Summary | |
---|---|
static class | Character.Subset Instances of this class represent particular subsets of the Unicode character set. |
static class | Character.UnicodeBlock A family of character subsets representing the character blocks in the Unicode specification. |
Field Summary | |
---|---|
static byte | COMBINING_SPACING_MARK General category "Mc" in the Unicode specification. |
static byte | CONNECTOR_PUNCTUATION General category "Pc" in the Unicode specification. |
static byte | CONTROL General category "Cc" in the Unicode specification. |
static byte | CURRENCY_SYMBOL General category "Sc" in the Unicode specification. |
static byte | DASH_PUNCTUATION General category "Pd" in the Unicode specification. |
static byte | DECIMAL_DIGIT_NUMBER General category "Nd" in the Unicode specification. |
static byte | DIRECTIONALITY_ARABIC_NUMBER Weak bidirectional character type "AN" in the Unicode specification. |
static byte | DIRECTIONALITY_BOUNDARY_NEUTRAL Weak bidirectional character type "BN" in the Unicode specification. |
static byte | DIRECTIONALITY_COMMON_NUMBER_SEPARATOR Weak bidirectional character type "CS" in the Unicode specification. |
static byte | DIRECTIONALITY_EUROPEAN_NUMBER Weak bidirectional character type "EN" in the Unicode specification. |
static byte | DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR Weak bidirectional character type "ES" in the Unicode specification. |
static byte | DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR Weak bidirectional character type "ET" in the Unicode specification. |
static byte | DIRECTIONALITY_LEFT_TO_RIGHT Strong bidirectional character type "L" in the Unicode specification. |
static byte | DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING Strong bidirectional character type "LRE" in the Unicode specification. |
static byte | DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE Strong bidirectional character type "LRO" in the Unicode specification. |
static byte | DIRECTIONALITY_NONSPACING_MARK Weak bidirectional character type "NSM" in the Unicode specification. |
static byte | DIRECTIONALITY_OTHER_NEUTRALS Neutral bidirectional character type "ON" in the Unicode specification. |
static byte | DIRECTIONALITY_PARAGRAPH_SEPARATOR Neutral bidirectional character type "B" in the Unicode specification. |
static byte | DIRECTIONALITY_POP_DIRECTIONAL_FORMAT Weak bidirectional character type "PDF" in the Unicode specification. |
static byte | DIRECTIONALITY_RIGHT_TO_LEFT Strong bidirectional character type "R" in the Unicode specification. |
static byte | DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC Strong bidirectional character type "AL" in the Unicode specification. |
static byte | DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING Strong bidirectional character type "RLE" in the Unicode specification. |
static byte | DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE Strong bidirectional character type "RLO" in the Unicode specification. |
static byte | DIRECTIONALITY_SEGMENT_SEPARATOR Neutral bidirectional character type "S" in the Unicode specification. |
static byte | DIRECTIONALITY_UNDEFINED Undefined bidirectional character type. |
static byte | DIRECTIONALITY_WHITESPACE Neutral bidirectional character type "WS" in the Unicode specification. |
static byte | ENCLOSING_MARK General category "Me" in the Unicode specification. |
static byte | END_PUNCTUATION General category "Pe" in the Unicode specification. |
static byte | FINAL_QUOTE_PUNCTUATION General category "Pf" in the Unicode specification. |
static byte | FORMAT General category "Cf" in the Unicode specification. |
static byte | INITIAL_QUOTE_PUNCTUATION General category "Pi" in the Unicode specification. |
static byte | LETTER_NUMBER General category "Nl" in the Unicode specification. |
static byte | LINE_SEPARATOR General category "Zl" in the Unicode specification. |
static byte | LOWERCASE_LETTER General category "Ll" in the Unicode specification. |
static byte | MATH_SYMBOL General category "Sm" in the Unicode specification. |
static int | MAX_CODE_POINT The maximum value of a Unicode code point. |
static char | MAX_HIGH_SURROGATE The maximum value of a Unicode high-surrogate code unit in the UTF-16 encoding. |
static char | MAX_LOW_SURROGATE The maximum value of a Unicode low-surrogate code unit in the UTF-16 encoding. |
static int | MAX_RADIX The maximum radix available for conversion to and from strings. |
static char | MAX_SURROGATE The maximum value of a Unicode surrogate code unit in the UTF-16 encoding. |
static char | MAX_VALUE The constant value of this field is the largest value of typechar, '\uFFFF'. |
static int | MIN_CODE_POINT The minimum value of a Unicode code point. |
static char | MIN_HIGH_SURROGATE The minimum value of a Unicode high-surrogate code unit in the UTF-16 encoding. |
static char | MIN_LOW_SURROGATE The minimum value of a Unicode low-surrogate code unit in the UTF-16 encoding. |
static int | MIN_RADIX The minimum radix available for conversion to and from strings. |
static int | MIN_SUPPLEMENTARY_CODE_POINT The minimum value of a supplementary code point. |
static char | MIN_SURROGATE The minimum value of a Unicode surrogate code unit in the UTF-16 encoding. |
static char | MIN_VALUE The constant value of this field is the smallest value of typechar, '\u0000'. |
static byte | MODIFIER_LETTER General category "Lm" in the Unicode specification. |
static byte | MODIFIER_SYMBOL General category "Sk" in the Unicode specification. |
static byte | NON_SPACING_MARK General category "Mn" in the Unicode specification. |
static byte | OTHER_LETTER General category "Lo" in the Unicode specification. |
static byte | OTHER_NUMBER General category "No" in the Unicode specification. |
static byte | OTHER_PUNCTUATION General category "Po" in the Unicode specification. |
static byte | OTHER_SYMBOL General category "So" in the Unicode specification. |
static byte | PARAGRAPH_SEPARATOR General category "Zp" in the Unicode specification. |
static byte | PRIVATE_USE General category "Co" in the Unicode specification. |
static int | SIZE The number of bits used to represent a char value in unsigned binary form. |
static byte | SPACE_SEPARATOR General category "Zs" in the Unicode specification. |
static byte | START_PUNCTUATION General category "Ps" in the Unicode specification. |
static byte | SURROGATE General category "Cs" in the Unicode specification. |
static byte | TITLECASE_LETTER General category "Lt" in the Unicode specification. |
static Class<Character> | TYPE The Class instance representing the primitive typechar. |
static byte | UNASSIGNED General category "Cn" in the Unicode specification. |
static byte | UPPERCASE_LETTER General category "Lu" in the Unicode specification. |
Constructor Summary |
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Character(char value) Constructs a newly allocated Character object that represents the specified char value. |
Method Summary | |
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static int | charCount(int codePoint) Determines the number of char values needed to represent the specified character (Unicode code point). |
char | charValue() Returns the value of this Character object. |
static int | [codePointAt](../../java/lang/Character.html#codePointAt%28char[], int%29)(char[] a, int index) Returns the code point at the given index of thechar array. |
static int | [codePointAt](../../java/lang/Character.html#codePointAt%28char[], int, int%29)(char[] a, int index, int limit) Returns the code point at the given index of thechar array, where only array elements withindex less than limit can be used. |
static int | [codePointAt](../../java/lang/Character.html#codePointAt%28java.lang.CharSequence, int%29)(CharSequence seq, int index) Returns the code point at the given index of theCharSequence. |
static int | [codePointBefore](../../java/lang/Character.html#codePointBefore%28char[], int%29)(char[] a, int index) Returns the code point preceding the given index of thechar array. |
static int | [codePointBefore](../../java/lang/Character.html#codePointBefore%28char[], int, int%29)(char[] a, int index, int start) Returns the code point preceding the given index of thechar array, where only array elements withindex greater than or equal to start can be used. |
static int | [codePointBefore](../../java/lang/Character.html#codePointBefore%28java.lang.CharSequence, int%29)(CharSequence seq, int index) Returns the code point preceding the given index of theCharSequence. |
static int | [codePointCount](../../java/lang/Character.html#codePointCount%28char[], int, int%29)(char[] a, int offset, int count) Returns the number of Unicode code points in a subarray of thechar array argument. |
static int | [codePointCount](../../java/lang/Character.html#codePointCount%28java.lang.CharSequence, int, int%29)(CharSequence seq, int beginIndex, int endIndex) Returns the number of Unicode code points in the text range of the specified char sequence. |
int | compareTo(Character anotherCharacter) Compares two Character objects numerically. |
static int | [digit](../../java/lang/Character.html#digit%28char, int%29)(char ch, int radix) Returns the numeric value of the character ch in the specified radix. |
static int | [digit](../../java/lang/Character.html#digit%28int, int%29)(int codePoint, int radix) Returns the numeric value of the specified character (Unicode code point) in the specified radix. |
boolean | equals(Object obj) Compares this object against the specified object. |
static char | [forDigit](../../java/lang/Character.html#forDigit%28int, int%29)(int digit, int radix) Determines the character representation for a specific digit in the specified radix. |
static byte | getDirectionality(char ch) Returns the Unicode directionality property for the given character. |
static byte | getDirectionality(int codePoint) Returns the Unicode directionality property for the given character (Unicode code point). |
static int | getNumericValue(char ch) Returns the int value that the specified Unicode character represents. |
static int | getNumericValue(int codePoint) Returns the int value that the specified character (Unicode code point) represents. |
static int | getType(char ch) Returns a value indicating a character's general category. |
static int | getType(int codePoint) Returns a value indicating a character's general category. |
int | hashCode() Returns a hash code for this Character. |
static boolean | isDefined(char ch) Determines if a character is defined in Unicode. |
static boolean | isDefined(int codePoint) Determines if a character (Unicode code point) is defined in Unicode. |
static boolean | isDigit(char ch) Determines if the specified character is a digit. |
static boolean | isDigit(int codePoint) Determines if the specified character (Unicode code point) is a digit. |
static boolean | isHighSurrogate(char ch) Determines if the given char value is a high-surrogate code unit (also known as leading-surrogate code unit). |
static boolean | isIdentifierIgnorable(char ch) Determines if the specified character should be regarded as an ignorable character in a Java identifier or a Unicode identifier. |
static boolean | isIdentifierIgnorable(int codePoint) Determines if the specified character (Unicode code point) should be regarded as an ignorable character in a Java identifier or a Unicode identifier. |
static boolean | isISOControl(char ch) Determines if the specified character is an ISO control character. |
static boolean | isISOControl(int codePoint) Determines if the referenced character (Unicode code point) is an ISO control character. |
static boolean | isJavaIdentifierPart(char ch) Determines if the specified character may be part of a Java identifier as other than the first character. |
static boolean | isJavaIdentifierPart(int codePoint) Determines if the character (Unicode code point) may be part of a Java identifier as other than the first character. |
static boolean | isJavaIdentifierStart(char ch) Determines if the specified character is permissible as the first character in a Java identifier. |
static boolean | isJavaIdentifierStart(int codePoint) Determines if the character (Unicode code point) is permissible as the first character in a Java identifier. |
static boolean | isJavaLetter(char ch) Deprecated. Replaced by isJavaIdentifierStart(char). |
static boolean | isJavaLetterOrDigit(char ch) Deprecated. Replaced by isJavaIdentifierPart(char). |
static boolean | isLetter(char ch) Determines if the specified character is a letter. |
static boolean | isLetter(int codePoint) Determines if the specified character (Unicode code point) is a letter. |
static boolean | isLetterOrDigit(char ch) Determines if the specified character is a letter or digit. |
static boolean | isLetterOrDigit(int codePoint) Determines if the specified character (Unicode code point) is a letter or digit. |
static boolean | isLowerCase(char ch) Determines if the specified character is a lowercase character. |
static boolean | isLowerCase(int codePoint) Determines if the specified character (Unicode code point) is a lowercase character. |
static boolean | isLowSurrogate(char ch) Determines if the given char value is a low-surrogate code unit (also known as trailing-surrogate code unit). |
static boolean | isMirrored(char ch) Determines whether the character is mirrored according to the Unicode specification. |
static boolean | isMirrored(int codePoint) Determines whether the specified character (Unicode code point) is mirrored according to the Unicode specification. |
static boolean | isSpace(char ch) Deprecated. Replaced by isWhitespace(char). |
static boolean | isSpaceChar(char ch) Determines if the specified character is a Unicode space character. |
static boolean | isSpaceChar(int codePoint) Determines if the specified character (Unicode code point) is a Unicode space character. |
static boolean | isSupplementaryCodePoint(int codePoint) Determines whether the specified character (Unicode code point) is in the supplementary character range. |
static boolean | [isSurrogatePair](../../java/lang/Character.html#isSurrogatePair%28char, char%29)(char high, char low) Determines whether the specified pair of char values is a valid surrogate pair. |
static boolean | isTitleCase(char ch) Determines if the specified character is a titlecase character. |
static boolean | isTitleCase(int codePoint) Determines if the specified character (Unicode code point) is a titlecase character. |
static boolean | isUnicodeIdentifierPart(char ch) Determines if the specified character may be part of a Unicode identifier as other than the first character. |
static boolean | isUnicodeIdentifierPart(int codePoint) Determines if the specified character (Unicode code point) may be part of a Unicode identifier as other than the first character. |
static boolean | isUnicodeIdentifierStart(char ch) Determines if the specified character is permissible as the first character in a Unicode identifier. |
static boolean | isUnicodeIdentifierStart(int codePoint) Determines if the specified character (Unicode code point) is permissible as the first character in a Unicode identifier. |
static boolean | isUpperCase(char ch) Determines if the specified character is an uppercase character. |
static boolean | isUpperCase(int codePoint) Determines if the specified character (Unicode code point) is an uppercase character. |
static boolean | isValidCodePoint(int codePoint) Determines whether the specified code point is a valid Unicode code point value in the range of 0x0000 to0x10FFFF inclusive. |
static boolean | isWhitespace(char ch) Determines if the specified character is white space according to Java. |
static boolean | isWhitespace(int codePoint) Determines if the specified character (Unicode code point) is white space according to Java. |
static int | [offsetByCodePoints](../../java/lang/Character.html#offsetByCodePoints%28char[], int, int, int, int%29)(char[] a, int start, int count, int index, int codePointOffset) Returns the index within the given char subarray that is offset from the given index bycodePointOffset code points. |
static int | [offsetByCodePoints](../../java/lang/Character.html#offsetByCodePoints%28java.lang.CharSequence, int, int%29)(CharSequence seq, int index, int codePointOffset) Returns the index within the given char sequence that is offset from the given index by codePointOffset code points. |
static char | reverseBytes(char ch) Returns the value obtained by reversing the order of the bytes in the specified char value. |
static char[] | toChars(int codePoint) Converts the specified character (Unicode code point) to its UTF-16 representation stored in a char array. |
static int | [toChars](../../java/lang/Character.html#toChars%28int, char[], int%29)(int codePoint, char[] dst, int dstIndex) Converts the specified character (Unicode code point) to its UTF-16 representation. |
static int | [toCodePoint](../../java/lang/Character.html#toCodePoint%28char, char%29)(char high, char low) Converts the specified surrogate pair to its supplementary code point value. |
static char | toLowerCase(char ch) Converts the character argument to lowercase using case mapping information from the UnicodeData file. |
static int | toLowerCase(int codePoint) Converts the character (Unicode code point) argument to lowercase using case mapping information from the UnicodeData file. |
String | toString() Returns a String object representing thisCharacter's value. |
static String | toString(char c) Returns a String object representing the specified char. |
static char | toTitleCase(char ch) Converts the character argument to titlecase using case mapping information from the UnicodeData file. |
static int | toTitleCase(int codePoint) Converts the character (Unicode code point) argument to titlecase using case mapping information from the UnicodeData file. |
static char | toUpperCase(char ch) Converts the character argument to uppercase using case mapping information from the UnicodeData file. |
static int | toUpperCase(int codePoint) Converts the character (Unicode code point) argument to uppercase using case mapping information from the UnicodeData file. |
static Character | valueOf(char c) Returns a Character instance representing the specifiedchar value. |
Methods inherited from class java.lang.Object |
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clone, finalize, getClass, notify, notifyAll, wait, wait, [wait](../../java/lang/Object.html#wait%28long, int%29) |
Field Detail |
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MIN_RADIX
public static final int MIN_RADIX
The 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 thedigit
method, the forDigit
method, and the toString
method of classInteger
.
See Also:
[digit(char, int)](../../java/lang/Character.html#digit%28char, int%29), [forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), [Integer.toString(int, int)](../../java/lang/Integer.html#toString%28int, int%29), Integer.valueOf(java.lang.String), Constant Field Values
MAX_RADIX
public static final int MAX_RADIX
The 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 thedigit
method, the forDigit
method, and the toString
method of classInteger
.
See Also:
[digit(char, int)](../../java/lang/Character.html#digit%28char, int%29), [forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), [Integer.toString(int, int)](../../java/lang/Integer.html#toString%28int, int%29), Integer.valueOf(java.lang.String), Constant Field Values
MIN_VALUE
public static final char MIN_VALUE
The constant value of this field is the smallest value of typechar
, '\u0000'
.
Since:
1.0.2
See Also:
MAX_VALUE
public static final char MAX_VALUE
The constant value of this field is the largest value of typechar
, '\uFFFF'
.
Since:
1.0.2
See Also:
TYPE
public static final Class<Character> TYPE
The Class
instance representing the primitive typechar
.
Since:
1.1
UNASSIGNED
public static final byte UNASSIGNED
General category "Cn" in the Unicode specification.
Since:
1.1
See Also:
UPPERCASE_LETTER
public static final byte UPPERCASE_LETTER
General category "Lu" in the Unicode specification.
Since:
1.1
See Also:
LOWERCASE_LETTER
public static final byte LOWERCASE_LETTER
General category "Ll" in the Unicode specification.
Since:
1.1
See Also:
TITLECASE_LETTER
public static final byte TITLECASE_LETTER
General category "Lt" in the Unicode specification.
Since:
1.1
See Also:
MODIFIER_LETTER
public static final byte MODIFIER_LETTER
General category "Lm" in the Unicode specification.
Since:
1.1
See Also:
OTHER_LETTER
public static final byte OTHER_LETTER
General category "Lo" in the Unicode specification.
Since:
1.1
See Also:
NON_SPACING_MARK
public static final byte NON_SPACING_MARK
General category "Mn" in the Unicode specification.
Since:
1.1
See Also:
ENCLOSING_MARK
public static final byte ENCLOSING_MARK
General category "Me" in the Unicode specification.
Since:
1.1
See Also:
COMBINING_SPACING_MARK
public static final byte COMBINING_SPACING_MARK
General category "Mc" in the Unicode specification.
Since:
1.1
See Also:
DECIMAL_DIGIT_NUMBER
public static final byte DECIMAL_DIGIT_NUMBER
General category "Nd" in the Unicode specification.
Since:
1.1
See Also:
LETTER_NUMBER
public static final byte LETTER_NUMBER
General category "Nl" in the Unicode specification.
Since:
1.1
See Also:
OTHER_NUMBER
public static final byte OTHER_NUMBER
General category "No" in the Unicode specification.
Since:
1.1
See Also:
SPACE_SEPARATOR
public static final byte SPACE_SEPARATOR
General category "Zs" in the Unicode specification.
Since:
1.1
See Also:
LINE_SEPARATOR
public static final byte LINE_SEPARATOR
General category "Zl" in the Unicode specification.
Since:
1.1
See Also:
PARAGRAPH_SEPARATOR
public static final byte PARAGRAPH_SEPARATOR
General category "Zp" in the Unicode specification.
Since:
1.1
See Also:
CONTROL
public static final byte CONTROL
General category "Cc" in the Unicode specification.
Since:
1.1
See Also:
FORMAT
public static final byte FORMAT
General category "Cf" in the Unicode specification.
Since:
1.1
See Also:
PRIVATE_USE
public static final byte PRIVATE_USE
General category "Co" in the Unicode specification.
Since:
1.1
See Also:
SURROGATE
public static final byte SURROGATE
General category "Cs" in the Unicode specification.
Since:
1.1
See Also:
DASH_PUNCTUATION
public static final byte DASH_PUNCTUATION
General category "Pd" in the Unicode specification.
Since:
1.1
See Also:
START_PUNCTUATION
public static final byte START_PUNCTUATION
General category "Ps" in the Unicode specification.
Since:
1.1
See Also:
END_PUNCTUATION
public static final byte END_PUNCTUATION
General category "Pe" in the Unicode specification.
Since:
1.1
See Also:
CONNECTOR_PUNCTUATION
public static final byte CONNECTOR_PUNCTUATION
General category "Pc" in the Unicode specification.
Since:
1.1
See Also:
OTHER_PUNCTUATION
public static final byte OTHER_PUNCTUATION
General category "Po" in the Unicode specification.
Since:
1.1
See Also:
MATH_SYMBOL
public static final byte MATH_SYMBOL
General category "Sm" in the Unicode specification.
Since:
1.1
See Also:
CURRENCY_SYMBOL
public static final byte CURRENCY_SYMBOL
General category "Sc" in the Unicode specification.
Since:
1.1
See Also:
MODIFIER_SYMBOL
public static final byte MODIFIER_SYMBOL
General category "Sk" in the Unicode specification.
Since:
1.1
See Also:
OTHER_SYMBOL
public static final byte OTHER_SYMBOL
General category "So" in the Unicode specification.
Since:
1.1
See Also:
INITIAL_QUOTE_PUNCTUATION
public static final byte INITIAL_QUOTE_PUNCTUATION
General category "Pi" in the Unicode specification.
Since:
1.4
See Also:
FINAL_QUOTE_PUNCTUATION
public static final byte FINAL_QUOTE_PUNCTUATION
General category "Pf" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_UNDEFINED
public static final byte DIRECTIONALITY_UNDEFINED
Undefined bidirectional character type. Undefined char
values have undefined directionality in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_LEFT_TO_RIGHT
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT
Strong bidirectional character type "L" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_RIGHT_TO_LEFT
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT
Strong bidirectional character type "R" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC
Strong bidirectional character type "AL" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_EUROPEAN_NUMBER
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER
Weak bidirectional character type "EN" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR
Weak bidirectional character type "ES" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR
public static final byte DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR
Weak bidirectional character type "ET" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_ARABIC_NUMBER
public static final byte DIRECTIONALITY_ARABIC_NUMBER
Weak bidirectional character type "AN" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_COMMON_NUMBER_SEPARATOR
public static final byte DIRECTIONALITY_COMMON_NUMBER_SEPARATOR
Weak bidirectional character type "CS" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_NONSPACING_MARK
public static final byte DIRECTIONALITY_NONSPACING_MARK
Weak bidirectional character type "NSM" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_BOUNDARY_NEUTRAL
public static final byte DIRECTIONALITY_BOUNDARY_NEUTRAL
Weak bidirectional character type "BN" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_PARAGRAPH_SEPARATOR
public static final byte DIRECTIONALITY_PARAGRAPH_SEPARATOR
Neutral bidirectional character type "B" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_SEGMENT_SEPARATOR
public static final byte DIRECTIONALITY_SEGMENT_SEPARATOR
Neutral bidirectional character type "S" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_WHITESPACE
public static final byte DIRECTIONALITY_WHITESPACE
Neutral bidirectional character type "WS" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_OTHER_NEUTRALS
public static final byte DIRECTIONALITY_OTHER_NEUTRALS
Neutral bidirectional character type "ON" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING
Strong bidirectional character type "LRE" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE
public static final byte DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE
Strong bidirectional character type "LRO" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING
Strong bidirectional character type "RLE" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE
public static final byte DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE
Strong bidirectional character type "RLO" in the Unicode specification.
Since:
1.4
See Also:
DIRECTIONALITY_POP_DIRECTIONAL_FORMAT
public static final byte DIRECTIONALITY_POP_DIRECTIONAL_FORMAT
Weak bidirectional character type "PDF" in the Unicode specification.
Since:
1.4
See Also:
MIN_HIGH_SURROGATE
public static final char MIN_HIGH_SURROGATE
The minimum value of a Unicode high-surrogate code unit in the UTF-16 encoding. A high-surrogate is also known as a_leading-surrogate_.
Since:
1.5
See Also:
MAX_HIGH_SURROGATE
public static final char MAX_HIGH_SURROGATE
The maximum value of a Unicode high-surrogate code unit in the UTF-16 encoding. A high-surrogate is also known as a_leading-surrogate_.
Since:
1.5
See Also:
MIN_LOW_SURROGATE
public static final char MIN_LOW_SURROGATE
The minimum value of a Unicode low-surrogate code unit in the UTF-16 encoding. A low-surrogate is also known as a_trailing-surrogate_.
Since:
1.5
See Also:
MAX_LOW_SURROGATE
public static final char MAX_LOW_SURROGATE
The maximum value of a Unicode low-surrogate code unit in the UTF-16 encoding. A low-surrogate is also known as a_trailing-surrogate_.
Since:
1.5
See Also:
MIN_SURROGATE
public static final char MIN_SURROGATE
The minimum value of a Unicode surrogate code unit in the UTF-16 encoding.
Since:
1.5
See Also:
MAX_SURROGATE
public static final char MAX_SURROGATE
The maximum value of a Unicode surrogate code unit in the UTF-16 encoding.
Since:
1.5
See Also:
MIN_SUPPLEMENTARY_CODE_POINT
public static final int MIN_SUPPLEMENTARY_CODE_POINT
The minimum value of a supplementary code point.
Since:
1.5
See Also:
MIN_CODE_POINT
public static final int MIN_CODE_POINT
The minimum value of a Unicode code point.
Since:
1.5
See Also:
MAX_CODE_POINT
public static final int MAX_CODE_POINT
The maximum value of a Unicode code point.
Since:
1.5
See Also:
SIZE
public static final int SIZE
The number of bits used to represent a char value in unsigned binary form.
Since:
1.5
See Also:
Constructor Detail |
---|
Character
public Character(char value)
Constructs a newly allocated Character
object that represents the specified char
value.
Parameters:
value
- the value to be represented by the Character
object.
Method Detail |
---|
valueOf
public static Character valueOf(char c)
Returns a Character instance representing the specifiedchar value. If a new Character instance 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.
Parameters:
c
- a char value.
Returns:
a Character instance representing c.
Since:
1.5
charValue
public char charValue()
Returns the value of this Character
object.
Returns:
the primitive char
value represented by this object.
hashCode
public int hashCode()
Returns a hash code for this Character
.
Overrides:
[hashCode](../../java/lang/Object.html#hashCode%28%29)
in class [Object](../../java/lang/Object.html "class in java.lang")
Returns:
a hash code value for this object.
See Also:
Object.equals(java.lang.Object), Hashtable
equals
public boolean equals(Object obj)
Compares this object against the specified object. The result is true
if and only if the argument is notnull
and is a Character
object that represents the same char
value as this object.
Overrides:
[equals](../../java/lang/Object.html#equals%28java.lang.Object%29)
in class [Object](../../java/lang/Object.html "class in java.lang")
Parameters:
obj
- the object to compare with.
Returns:
true
if the objects are the same;false
otherwise.
See Also:
toString
public String toString()
Returns a String
object representing thisCharacter
's value. The result is a string of length 1 whose sole component is the primitivechar
value represented by thisCharacter
object.
Overrides:
[toString](../../java/lang/Object.html#toString%28%29)
in class [Object](../../java/lang/Object.html "class in java.lang")
Returns:
a string representation of this object.
toString
public static String toString(char c)
Returns a String
object representing the specified char
. The result is a string of length 1 consisting solely of the specified char
.
Parameters:
c
- the char
to be converted
Returns:
the string representation of the specified char
Since:
1.4
isValidCodePoint
public static boolean isValidCodePoint(int codePoint)
Determines whether the specified code point is a valid Unicode code point value in the range of 0x0000
to0x10FFFF
inclusive. This method is equivalent to the expression:
codePoint >= 0x0000 && codePoint <= 0x10FFFF
Parameters:
codePoint
- the Unicode code point to be tested
Returns:
true
if the specified code point value is a valid code point value;false
otherwise.
Since:
1.5
isSupplementaryCodePoint
public static boolean isSupplementaryCodePoint(int codePoint)
Determines whether the specified character (Unicode code point) is in the supplementary character range. The method call is equivalent to the expression:
codePoint >= 0x10000 && codePoint <= 0x10ffff
Parameters:
codePoint
- the character (Unicode code point) to be tested
Returns:
true
if the specified character is in the Unicode supplementary character range; false
otherwise.
Since:
1.5
isHighSurrogate
public static boolean isHighSurrogate(char ch)
Determines if the given char
value is a 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.
This method returns true
if and only if
ch >= '\uD800' && ch <= '\uDBFF'
is true
.
Parameters:
ch
- the char
value to be tested.
Returns:
true
if the char
value is between '\uD800' and '\uDBFF' inclusive;false
otherwise.
Since:
1.5
See Also:
isLowSurrogate(char), Character.UnicodeBlock.of(int)
isLowSurrogate
public static boolean isLowSurrogate(char ch)
Determines if the given char
value is a 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.
This method returns true
if and only if
ch >= '\uDC00' && ch <= '\uDFFF'
is true
.
Parameters:
ch
- the char
value to be tested.
Returns:
true
if the char
value is between '\uDC00' and '\uDFFF' inclusive;false
otherwise.
Since:
1.5
See Also:
isSurrogatePair
public static boolean isSurrogatePair(char high, char low)
Determines whether the specified pair of char
values is a valid surrogate pair. This method is equivalent to the expression:
isHighSurrogate(high) && isLowSurrogate(low)
Parameters:
high
- the high-surrogate code value to be tested
low
- the low-surrogate code value to be tested
Returns:
true
if the specified high and low-surrogate code values represent a valid surrogate pair;false
otherwise.
Since:
1.5
charCount
public static int charCount(int codePoint)
Determines the number of char
values needed to represent the specified character (Unicode code point). If the specified character is equal to or greater than 0x10000, then the method returns 2. Otherwise, the method returns 1.
This method doesn't validate the specified character to be a valid Unicode code point. The caller must validate the character value using isValidCodePoint if 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
See Also:
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 using [isSurrogatePair](../../java/lang/Character.html#isSurrogatePair%28char, char%29) if necessary.
Parameters:
high
- the high-surrogate code unit
low
- the low-surrogate code unit
Returns:
the supplementary code point composed from the specified surrogate pair.
Since:
1.5
codePointAt
public static int codePointAt(CharSequence seq, int index)
Returns the code point at the given index of theCharSequence
. If the char
value at the given index in the CharSequence
is in the high-surrogate range, the following index is less than the length of the CharSequence
, and thechar
value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char
value at the given index is returned.
Parameters:
seq
- a sequence of char
values (Unicode code units)
index
- the index to the char
values (Unicode code units) in seq
to be converted
Returns:
the Unicode code point at the given index
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if seq
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if the valueindex
is negative or not less thanseq.length().
Since:
1.5
codePointAt
public static int codePointAt(char[] a, int index)
Returns the code point at the given index of thechar
array. If the char
value at the given index in the char
array is in the high-surrogate range, the following index is less than the length of the char
array, and thechar
value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char
value at the given index is returned.
Parameters:
a
- the char
array
index
- the index to the char
values (Unicode code units) in the char
array to be converted
Returns:
the Unicode code point at the given index
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if a
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if the valueindex
is negative or not less than the length of the char
array.
Since:
1.5
codePointAt
public static int codePointAt(char[] a, int index, int limit)
Returns the code point at the given index of thechar
array, where only array elements withindex
less than limit
can be used. If the char
value at the given index in thechar
array is in the high-surrogate range, the following index is less than the limit
, and thechar
value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char
value at the given index is returned.
Parameters:
a
- the char
array
index
- the index to the char
values (Unicode code units) in the char
array to be converted
limit
- the index after the last array element that can be used in thechar
array
Returns:
the Unicode code point at the given index
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if a
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if the index
argument is negative or not less than the limit
argument, or if the limit
argument is negative or greater than the length of the char
array.
Since:
1.5
codePointBefore
public static int codePointBefore(CharSequence seq, int index)
Returns the code point preceding the given index of theCharSequence
. If the char
value at(index - 1)
in the CharSequence
is in the low-surrogate range, (index - 2)
is not negative, and the char
value at (index - 2)
in the CharSequence
is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char
value at (index - 1)
is returned.
Parameters:
seq
- the CharSequence
instance
index
- the index following the code point that should be returned
Returns:
the Unicode code point value before the given index.
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if seq
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if the index
argument is less than 1 or greater than seq.length().
Since:
1.5
codePointBefore
public static int codePointBefore(char[] a, int index)
Returns the code point preceding the given index of thechar
array. If the char
value at(index - 1)
in the char
array is in the low-surrogate range, (index - 2)
is not negative, and the char
value at (index - 2)
in the char
array is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char
value at (index - 1)
is returned.
Parameters:
a
- the char
array
index
- the index following the code point that should be returned
Returns:
the Unicode code point value before the given index.
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if a
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if the index
argument is less than 1 or greater than the length of thechar
array
Since:
1.5
codePointBefore
public static int codePointBefore(char[] a, int index, int start)
Returns the code point preceding the given index of thechar
array, where only array elements withindex
greater than or equal to start
can be used. If the char
value at (index - 1)
in the char
array is in the low-surrogate range, (index - 2)
is not less thanstart
, and the char
value at(index - 2)
in the char
array is in the high-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char
value at (index - 1)
is returned.
Parameters:
a
- the char
array
index
- the index following the code point that should be returned
start
- the index of the first array element in thechar
array
Returns:
the Unicode code point value before the given index.
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if a
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if the index
argument is not greater than the start
argument or is greater than the length of the char
array, or if the start
argument is negative or not less than the length of the char
array.
Since:
1.5
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 in dst[dstIndex]
, and 1 is returned. If the specified code point is a supplementary character, its surrogate values are stored in dst[dstIndex]
(high-surrogate) and dst[dstIndex+1]
(low-surrogate), and 2 is returned.
Parameters:
codePoint
- the character (Unicode code point) to be converted.
dst
- an array of char
in which thecodePoint
's UTF-16 value is stored.
dstIndex
- the start index into the dst
array 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](../../java/lang/IllegalArgumentException.html "class in java.lang")
- if the specifiedcodePoint
is not a valid Unicode code point.
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if the specified dst
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if dstIndex
is negative or not less than dst.length
, or ifdst
at dstIndex
doesn't have enough array element(s) to store the resulting char
value(s). (If dstIndex
is equal todst.length-1
and the specifiedcodePoint
is a supplementary character, the high-surrogate value is not stored indst[dstIndex]
.)
Since:
1.5
toChars
public static char[] toChars(int codePoint)
Converts the specified character (Unicode code point) to its UTF-16 representation stored in a char
array. If the specified code point is a BMP (Basic Multilingual Plane or Plane 0) value, the resulting char
array has the same value as codePoint
. If the specified code point is a supplementary code point, the resultingchar
array has the corresponding surrogate pair.
Parameters:
codePoint
- a Unicode code point
Returns:
a char
array havingcodePoint
's UTF-16 representation.
Throws:
[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")
- if the specifiedcodePoint
is not a valid Unicode code point.
Since:
1.5
codePointCount
public static int codePointCount(CharSequence seq, int beginIndex, int endIndex)
Returns the number of Unicode code points in the text range of the specified char sequence. The text range begins at the specified beginIndex
and extends to thechar
at index endIndex - 1
. Thus the length (in char
s) of the text range isendIndex-beginIndex
. Unpaired surrogates within the text range count as one code point each.
Parameters:
seq
- the char sequence
beginIndex
- the index to the first char
of the text range.
endIndex
- the index after the last char
of the text range.
Returns:
the number of Unicode code points in the specified text range
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if seq
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if thebeginIndex
is negative, or endIndex
is larger than the length of the given sequence, orbeginIndex
is larger than endIndex
.
Since:
1.5
codePointCount
public static int codePointCount(char[] a, int offset, int count)
Returns the number of Unicode code points in a subarray of thechar
array argument. The offset
argument is the index of the first char
of the subarray and the count
argument specifies the length of the subarray in char
s. Unpaired surrogates within the subarray count as one code point each.
Parameters:
a
- the char
array
offset
- the index of the first char
in the given char
array
count
- the length of the subarray in char
s
Returns:
the number of Unicode code points in the specified subarray
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if a
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if offset
orcount
is negative, or if offset + count
is larger than the length of the given array.
Since:
1.5
offsetByCodePoints
public static int offsetByCodePoints(CharSequence seq, int index, int codePointOffset)
Returns the index within the given char sequence that is offset from the given index
by codePointOffset
code points. Unpaired surrogates within the text range given byindex
and codePointOffset
count as one code point each.
Parameters:
seq
- the char sequence
index
- the index to be offset
codePointOffset
- the offset in code points
Returns:
the index within the char sequence
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if seq
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if index
is negative or larger then the length of the char sequence, or if codePointOffset
is positive and the subsequence starting with index
has fewer thancodePointOffset
code points, or ifcodePointOffset
is negative and the subsequence before index
has fewer than the absolute value of codePointOffset
code points.
Since:
1.5
offsetByCodePoints
public static int offsetByCodePoints(char[] a, int start, int count, int index, int codePointOffset)
Returns the index within the given char
subarray that is offset from the given index
bycodePointOffset
code points. Thestart
and count
arguments specify a subarray of the char
array. Unpaired surrogates within the text range given by index
andcodePointOffset
count as one code point each.
Parameters:
a
- the char
array
start
- the index of the first char
of the subarray
count
- the length of the subarray in char
s
index
- the index to be offset
codePointOffset
- the offset in code points
Returns:
the index within the subarray
Throws:
[NullPointerException](../../java/lang/NullPointerException.html "class in java.lang")
- if a
is null.
[IndexOutOfBoundsException](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")
- if start
or count
is negative, or if start + count
is larger than the length of the given array, or if index
is less than start
or larger then start + count
, or if codePointOffset
is positive and the text range starting with index
and ending with start + count - 1
has fewer than codePointOffset
code points, or if codePointOffset
is negative and the text range starting with start
and ending with index - 1
has fewer than the absolute value ofcodePointOffset
code points.
Since:
1.5
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
.
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:
true
if the character is lowercase;false
otherwise.
See Also:
isLowerCase(char), isTitleCase(char), toLowerCase(char), getType(char)
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
.
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:
true
if the character is lowercase;false
otherwise.
Since:
1.5
See Also:
isLowerCase(int), isTitleCase(int), toLowerCase(int), getType(int)
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 byCharacter.getType(ch)
, is UPPERCASE_LETTER
.
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:
true
if the character is uppercase;false
otherwise.
Since:
1.0
See Also:
isLowerCase(char), isTitleCase(char), toUpperCase(char), getType(char)
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 bygetType(codePoint), is UPPERCASE_LETTER
.
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:
true
if the character is uppercase;false
otherwise.
Since:
1.5
See Also:
isLowerCase(int), isTitleCase(int), toUpperCase(int), getType(int)
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)
, is TITLECASE_LETTER
.
Some characters look like pairs of Latin letters. For example, there is an uppercase letter that looks like "LJ" and has a corresponding lowercase letter that looks like "lj". A third form, which looks like "Lj", is the appropriate form to use when rendering a word in lowercase with initial capitals, as for a book title.
These are some of the Unicode characters for which this method returnstrue
:
LATIN CAPITAL LETTER D WITH SMALL LETTER Z WITH CARON
LATIN CAPITAL LETTER L WITH SMALL LETTER J
LATIN CAPITAL LETTER N WITH SMALL LETTER J
LATIN 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:
true
if the character is titlecase;false
otherwise.
Since:
1.0.2
See Also:
isLowerCase(char), isUpperCase(char), toTitleCase(char), getType(char)
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), is TITLECASE_LETTER
.
Some characters look like pairs of Latin letters. For example, there is an uppercase letter that looks like "LJ" and has a corresponding lowercase letter that looks like "lj". A third form, which looks like "Lj", is the appropriate form to use when rendering a word in lowercase with initial capitals, as for a book title.
These are some of the Unicode characters for which this method returnstrue
:
LATIN CAPITAL LETTER D WITH SMALL LETTER Z WITH CARON
LATIN CAPITAL LETTER L WITH SMALL LETTER J
LATIN CAPITAL LETTER N WITH SMALL LETTER J
LATIN 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:
true
if the character is titlecase;false
otherwise.
Since:
1.5
See Also:
isLowerCase(int), isUpperCase(int), toTitleCase(int), getType(int)
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 Many other character ranges contain digits as well.
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:
true
if the character is a digit;false
otherwise.
See Also:
[digit(char, int)](../../java/lang/Character.html#digit%28char, int%29), [forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), getType(char)
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 Many other character ranges contain digits as well.
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character is a digit;false
otherwise.
Since:
1.5
See Also:
[forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), getType(int)
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:
true
if the character has a defined meaning in Unicode; false
otherwise.
Since:
1.0.2
See Also:
isDigit(char), isLetter(char), isLetterOrDigit(char), isLowerCase(char), isTitleCase(char), isUpperCase(char)
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:
true
if the character has a defined meaning in Unicode; false
otherwise.
Since:
1.5
See Also:
isDigit(int), isLetter(int), isLetterOrDigit(int), isLowerCase(int), isTitleCase(int), isUpperCase(int)
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
Not all letters have case. Many characters are letters but are neither uppercase nor lowercase nor titlecase.
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:
true
if the character is a letter;false
otherwise.
See Also:
isDigit(char), isJavaIdentifierStart(char), isJavaLetter(char), isJavaLetterOrDigit(char), isLetterOrDigit(char), isLowerCase(char), isTitleCase(char), isUnicodeIdentifierStart(char), isUpperCase(char)
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
Not all letters have case. Many characters are letters but are neither uppercase nor lowercase nor titlecase.
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character is a letter;false
otherwise.
Since:
1.5
See Also:
isDigit(int), isJavaIdentifierStart(int), isLetterOrDigit(int), isLowerCase(int), isTitleCase(int), isUnicodeIdentifierStart(int), isUpperCase(int)
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 eitherCharacter.isLetter(char ch)
orCharacter.isDigit(char ch)
returnstrue
for the character.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the isLetterOrDigit(int) method.
Parameters:
ch
- the character to be tested.
Returns:
true
if the character is a letter or digit;false
otherwise.
Since:
1.0.2
See Also:
isDigit(char), isJavaIdentifierPart(char), isJavaLetter(char), isJavaLetterOrDigit(char), isLetter(char), isUnicodeIdentifierPart(char)
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 eitherisLetter(codePoint) orisDigit(codePoint) returnstrue
for the character.
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character is a letter or digit;false
otherwise.
Since:
1.5
See Also:
isDigit(int), isJavaIdentifierPart(int), isLetter(int), isUnicodeIdentifierPart(int)
isJavaLetter
@Deprecated public static boolean isJavaLetter(char ch)
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 is true:
- isLetter(ch) returns
true
- getType(ch) returns
LETTER_NUMBER
- ch is a currency symbol (such as "$")
- ch is a connecting punctuation character (such as "_").
Parameters:
ch
- the character to be tested.
Returns:
true
if the character may start a Java identifier; false
otherwise.
Since:
1.02
See Also:
isJavaLetterOrDigit(char), isJavaIdentifierStart(char), isJavaIdentifierPart(char), isLetter(char), isLetterOrDigit(char), isUnicodeIdentifierStart(char)
isJavaLetterOrDigit
@Deprecated public static boolean isJavaLetterOrDigit(char ch)
Deprecated. Replaced by isJavaIdentifierPart(char).
Determines if the specified character may be part of a Java identifier as other than the first character.
A character may be part of a Java identifier if and only if any of the following are true:
- it is a letter
- it is a currency symbol (such as
'$'
) - 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
returnstrue
for the character.
Parameters:
ch
- the character to be tested.
Returns:
true
if the character may be part of a Java identifier; false
otherwise.
Since:
1.02
See Also:
isJavaLetter(char), isJavaIdentifierStart(char), isJavaIdentifierPart(char), isLetter(char), isLetterOrDigit(char), isUnicodeIdentifierPart(char), isIdentifierIgnorable(char)
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) returns
true
- getType(ch) returns
LETTER_NUMBER
- ch is a currency symbol (such as "$")
- ch is a connecting punctuation character (such as "_").
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the isJavaIdentifierStart(int) method.
Parameters:
ch
- the character to be tested.
Returns:
true
if the character may start a Java identifier;false
otherwise.
Since:
1.1
See Also:
isJavaIdentifierPart(char), isLetter(char), isUnicodeIdentifierStart(char)
isJavaIdentifierStart
public static boolean isJavaIdentifierStart(int codePoint)
Determines if the character (Unicode code point) is permissible as the first character in a Java identifier.
A character may start a Java identifier if and only if one of the following conditions is true:
- isLetter(codePoint) returns
true
- getType(codePoint) returns
LETTER_NUMBER
- the referenced character is a currency symbol (such as "$")
- the referenced character is a connecting punctuation character (such as "_").
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character may start a Java identifier;false
otherwise.
Since:
1.5
See Also:
isJavaIdentifierPart(int), isLetter(int), isUnicodeIdentifierStart(int)
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 are true:
- it is a letter
- it is a currency symbol (such as
'$'
) - it is a connecting punctuation character (such as
'_'
) - it is a digit
- it is a numeric letter (such as a Roman numeral character)
- it is a combining mark
- it is a non-spacing mark
isIdentifierIgnorable
returnstrue
for the character
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the isJavaIdentifierPart(int) method.
Parameters:
ch
- the character to be tested.
Returns:
true
if the character may be part of a Java identifier; false
otherwise.
Since:
1.1
See Also:
isIdentifierIgnorable(char), isJavaIdentifierStart(char), isLetterOrDigit(char), isUnicodeIdentifierPart(char)
isJavaIdentifierPart
public static boolean isJavaIdentifierPart(int codePoint)
Determines if the character (Unicode code point) may be part of a Java identifier as other than the first character.
A character may be part of a Java identifier if any of the following are true:
- it is a letter
- it is a currency symbol (such as
'$'
) - 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) returns
true
for the character
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character may be part of a Java identifier; false
otherwise.
Since:
1.5
See Also:
isIdentifierIgnorable(int), isJavaIdentifierStart(int), isLetterOrDigit(int), isUnicodeIdentifierPart(int)
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) returns
true
- getType(ch) returns
LETTER_NUMBER
.
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:
true
if the character may start a Unicode identifier; false
otherwise.
Since:
1.1
See Also:
isJavaIdentifierStart(char), isLetter(char), isUnicodeIdentifierPart(char)
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) returns
true
- getType(codePoint) returns
LETTER_NUMBER
.
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character may start a Unicode identifier; false
otherwise.
Since:
1.5
See Also:
isJavaIdentifierStart(int), isLetter(int), isUnicodeIdentifierPart(int)
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
isIdentifierIgnorable
returnstrue
for this character.
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:
true
if the character may be part of a Unicode identifier; false
otherwise.
Since:
1.1
See Also:
isIdentifierIgnorable(char), isJavaIdentifierPart(char), isLetterOrDigit(char), isUnicodeIdentifierStart(char)
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
isIdentifierIgnorable
returnstrue
for this character.
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character may be part of a Unicode identifier; false
otherwise.
Since:
1.5
See Also:
isIdentifierIgnorable(int), isJavaIdentifierPart(int), isLetterOrDigit(int), isUnicodeIdentifierStart(int)
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
FORMAT
general 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:
true
if the character is an ignorable control character that may be part of a Java or Unicode identifier;false
otherwise.
Since:
1.1
See Also:
isJavaIdentifierPart(char), isUnicodeIdentifierPart(char)
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
FORMAT
general category value
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character is an ignorable control character that may be part of a Java or Unicode identifier;false
otherwise.
Since:
1.5
See Also:
isJavaIdentifierPart(int), isUnicodeIdentifierPart(int)
toLowerCase
public static char toLowerCase(char ch)
Converts the character argument to lowercase using case mapping information from the UnicodeData file.
Note thatCharacter.isLowerCase(Character.toLowerCase(ch))
does not always return true
for some ranges of characters, particularly those that are symbols or ideographs.
In general, String.toLowerCase() should be used to map characters to lowercase. String
case mapping methods have several benefits over Character
case mapping methods.String
case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas the Character
case 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:
isLowerCase(char), String.toLowerCase()
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 thatCharacter.isLowerCase(Character.toLowerCase(codePoint))
does not always return true
for some ranges of characters, particularly those that are symbols or ideographs.
In general, String.toLowerCase() should be used to map characters to lowercase. String
case mapping methods have several benefits over Character
case mapping methods.String
case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas the Character
case 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:
isLowerCase(int), String.toLowerCase()
toUpperCase
public static char toUpperCase(char ch)
Converts the character argument to uppercase using case mapping information from the UnicodeData file.
Note thatCharacter.isUpperCase(Character.toUpperCase(ch))
does not always return true
for some ranges of characters, particularly those that are symbols or ideographs.
In general, String.toUpperCase() should be used to map characters to uppercase. String
case mapping methods have several benefits over Character
case mapping methods.String
case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas the Character
case 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:
isUpperCase(char), String.toUpperCase()
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 thatCharacter.isUpperCase(Character.toUpperCase(codePoint))
does not always return true
for some ranges of characters, particularly those that are symbols or ideographs.
In general, String.toUpperCase() should be used to map characters to uppercase. String
case mapping methods have several benefits over Character
case mapping methods.String
case mapping methods can perform locale-sensitive mappings, context-sensitive mappings, and 1:M character mappings, whereas the Character
case 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:
isUpperCase(int), String.toUpperCase()
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 thechar
argument is already a titlecasechar
, the same char
value will be returned.
Note thatCharacter.isTitleCase(Character.toTitleCase(ch))
does not always return true
for 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:
isTitleCase(char), toLowerCase(char), toUpperCase(char)
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 thatCharacter.isTitleCase(Character.toTitleCase(codePoint))
does not always return true
for 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:
isTitleCase(int), toLowerCase(int), toUpperCase(int)
digit
public static int digit(char ch, int radix)
Returns the numeric value of the character ch
in the specified radix.
If the radix is not in the range MIN_RADIX
<=radix
<= MAX_RADIX
or if the value of ch
is not a valid digit in the specified radix, -1
is returned. A character is a valid digit if at least one of the following is true:
- The method
isDigit
istrue
of the character and the Unicode decimal digit value of the character (or its single-character decomposition) is less than the specified radix. In this case the decimal digit value is returned. - 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' + 10
is 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' + 10
is returned.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the [digit(int, int)](../../java/lang/Character.html#digit%28int, int%29) 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:
[forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), isDigit(char)
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_RADIX
or if the character is not a valid digit in the specified radix, -1
is returned. A character is a valid digit if at least one of the following is true:
- The method isDigit(codePoint) is
true
of the character and the Unicode decimal digit value of the character (or its single-character decomposition) is less than the specified radix. In this case the decimal digit value is returned. - 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' + 10
is 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' + 10
is 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:
[forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), isDigit(int)
getNumericValue
public static int getNumericValue(char ch)
Returns the int
value that the specified Unicode character represents. For example, the character'\u216C'
(the roman numeral fifty) will return an int with a value of 50.
The letters A-Z in their uppercase ('\u0041'
through'\u005A'
), lowercase ('\u0061'
through '\u007A'
), and full width variant ('\uFF21'
through'\uFF3A'
and '\uFF41'
through'\uFF5A'
) forms have numeric values from 10 through 35. This is independent of the Unicode specification, which does not assign numeric values to these char
values.
If the character does not have a numeric value, then -1 is returned. If the character has a numeric value that cannot be represented as a nonnegative integer (for example, a fractional value), then -2 is returned.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the getNumericValue(int) method.
Parameters:
ch
- the character to be converted.
Returns:
the numeric value of the character, as a nonnegative int
value; -2 if the character has a numeric value that is not a nonnegative integer; -1 if the character has no numeric value.
Since:
1.1
See Also:
[forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), isDigit(char)
getNumericValue
public static int getNumericValue(int codePoint)
Returns the int
value that the specified character (Unicode code point) 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 these char
values.
If the character does not have a numeric value, then -1 is returned. If the character has a numeric value that cannot be represented as a nonnegative integer (for example, a fractional value), then -2 is returned.
Parameters:
codePoint
- the character (Unicode code point) to be converted.
Returns:
the numeric value of the character, as a nonnegative int
value; -2 if the character has a numeric value that is not a nonnegative integer; -1 if the character has no numeric value.
Since:
1.5
See Also:
[forDigit(int, int)](../../java/lang/Character.html#forDigit%28int, int%29), isDigit(int)
isSpace
@Deprecated public static boolean isSpace(char ch)
Deprecated. Replaced by isWhitespace(char).
Determines if the specified character is ISO-LATIN-1 white space. This method returns true
for the following five characters only:
'\t' | '\u0009' | HORIZONTAL TABULATION |
---|---|---|
'\n' | '\u000A' | NEW LINE |
'\f' | '\u000C' | FORM FEED |
'\r' | '\u000D' | CARRIAGE RETURN |
' ' | '\u0020' | SPACE |
Parameters:
ch
- the character to be tested.
Returns:
true
if the character is ISO-LATIN-1 white space; false
otherwise.
See Also:
isSpaceChar(char), isWhitespace(char)
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:
true
if the character is a space character; false
otherwise.
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:
true
if the character is a space character; false
otherwise.
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
'\u0009'
, HORIZONTAL TABULATION. - It is
'\u000A'
, LINE FEED. - It is
'\u000B'
, VERTICAL TABULATION. - It is
'\u000C'
, FORM FEED. - It is
'\u000D'
, CARRIAGE RETURN. - It is
'\u001C'
, FILE SEPARATOR. - It is
'\u001D'
, GROUP SEPARATOR. - It is
'\u001E'
, RECORD SEPARATOR. - It is
'\u001F'
, 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:
true
if the character is a Java whitespace character; false
otherwise.
Since:
1.1
See Also:
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, or PARAGRAPH_SEPARATOR) but is not also a non-breaking space (
'\u00A0'
,'\u2007'
,'\u202F'
). - It is
'\u0009'
, HORIZONTAL TABULATION. - It is
'\u000A'
, LINE FEED. - It is
'\u000B'
, VERTICAL TABULATION. - It is
'\u000C'
, FORM FEED. - It is
'\u000D'
, CARRIAGE RETURN. - It is
'\u001C'
, FILE SEPARATOR. - It is
'\u001D'
, GROUP SEPARATOR. - It is
'\u001E'
, RECORD SEPARATOR. - It is
'\u001F'
, UNIT SEPARATOR.
Parameters:
codePoint
- the character (Unicode code point) to be tested.
Returns:
true
if the character is a Java whitespace character; false
otherwise.
Since:
1.5
See Also:
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:
true
if the character is an ISO control character;false
otherwise.
Since:
1.1
See Also:
isSpaceChar(char), isWhitespace(char)
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:
true
if the character is an ISO control character;false
otherwise.
Since:
1.5
See Also:
isSpaceChar(int), isWhitespace(int)
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 int
representing the character's general category.
Since:
1.1
See Also:
COMBINING_SPACING_MARK, CONNECTOR_PUNCTUATION, CONTROL, CURRENCY_SYMBOL, DASH_PUNCTUATION, DECIMAL_DIGIT_NUMBER, ENCLOSING_MARK, END_PUNCTUATION, FINAL_QUOTE_PUNCTUATION, FORMAT, INITIAL_QUOTE_PUNCTUATION, LETTER_NUMBER, LINE_SEPARATOR, LOWERCASE_LETTER, MATH_SYMBOL, MODIFIER_LETTER, MODIFIER_SYMBOL, NON_SPACING_MARK, OTHER_LETTER, OTHER_NUMBER, OTHER_PUNCTUATION, OTHER_SYMBOL, PARAGRAPH_SEPARATOR, PRIVATE_USE, SPACE_SEPARATOR, START_PUNCTUATION, SURROGATE, TITLECASE_LETTER, UNASSIGNED, UPPERCASE_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 int
representing the character's general category.
Since:
1.5
See Also:
COMBINING_SPACING_MARK, CONNECTOR_PUNCTUATION, CONTROL, CURRENCY_SYMBOL, DASH_PUNCTUATION, DECIMAL_DIGIT_NUMBER, ENCLOSING_MARK, END_PUNCTUATION, FINAL_QUOTE_PUNCTUATION, FORMAT, INITIAL_QUOTE_PUNCTUATION, LETTER_NUMBER, LINE_SEPARATOR, LOWERCASE_LETTER, MATH_SYMBOL, MODIFIER_LETTER, MODIFIER_SYMBOL, NON_SPACING_MARK, OTHER_LETTER, OTHER_NUMBER, OTHER_PUNCTUATION, OTHER_SYMBOL, PARAGRAPH_SEPARATOR, PRIVATE_USE, SPACE_SEPARATOR, START_PUNCTUATION, SURROGATE, TITLECASE_LETTER, UNASSIGNED, UPPERCASE_LETTER
forDigit
public static char forDigit(int digit, int radix)
Determines the character representation for a specific digit in the specified radix. If the value of radix
is not a valid radix, or the value of digit
is not a valid digit in the specified radix, the null character ('\u0000'
) is returned.
The radix
argument is valid if it is greater than or equal to MIN_RADIX
and less than or equal toMAX_RADIX
. The digit
argument is valid if0 <=digit < radix
.
If the digit is less than 10, then'0' + digit
is returned. Otherwise, the value'a' + digit - 10
is returned.
Parameters:
digit
- the number to convert to a character.
radix
- the radix.
Returns:
the char
representation of the specified digit in the specified radix.
See Also:
MIN_RADIX, MAX_RADIX, [digit(char, int)](../../java/lang/Character.html#digit%28char, int%29)
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 undefinedchar
values is DIRECTIONALITY_UNDEFINED
.
Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the getDirectionality(int) method.
Parameters:
ch
- char
for which the directionality property is requested.
Returns:
the directionality property of the char
value.
Since:
1.4
See Also:
DIRECTIONALITY_UNDEFINED, DIRECTIONALITY_LEFT_TO_RIGHT, DIRECTIONALITY_RIGHT_TO_LEFT, DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC, DIRECTIONALITY_EUROPEAN_NUMBER, DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR, DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR, DIRECTIONALITY_ARABIC_NUMBER, DIRECTIONALITY_COMMON_NUMBER_SEPARATOR, DIRECTIONALITY_NONSPACING_MARK, DIRECTIONALITY_BOUNDARY_NEUTRAL, DIRECTIONALITY_PARAGRAPH_SEPARATOR, DIRECTIONALITY_SEGMENT_SEPARATOR, DIRECTIONALITY_WHITESPACE, DIRECTIONALITY_OTHER_NEUTRALS, DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING, DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE, DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING, DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE, DIRECTIONALITY_POP_DIRECTIONAL_FORMAT
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 is DIRECTIONALITY_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:
DIRECTIONALITY_UNDEFINED, DIRECTIONALITY_LEFT_TO_RIGHT, DIRECTIONALITY_RIGHT_TO_LEFT, DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC, DIRECTIONALITY_EUROPEAN_NUMBER, DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR, DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR, DIRECTIONALITY_ARABIC_NUMBER, DIRECTIONALITY_COMMON_NUMBER_SEPARATOR, DIRECTIONALITY_NONSPACING_MARK, DIRECTIONALITY_BOUNDARY_NEUTRAL, DIRECTIONALITY_PARAGRAPH_SEPARATOR, DIRECTIONALITY_SEGMENT_SEPARATOR, DIRECTIONALITY_WHITESPACE, DIRECTIONALITY_OTHER_NEUTRALS, DIRECTIONALITY_LEFT_TO_RIGHT_EMBEDDING, DIRECTIONALITY_LEFT_TO_RIGHT_OVERRIDE, DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING, DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE, DIRECTIONALITY_POP_DIRECTIONAL_FORMAT
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
- char
for which the mirrored property is requested
Returns:
true
if the char is mirrored, false
if the char
is not mirrored or is not defined.
Since:
1.4
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:
true
if the character is mirrored, false
if the character is not mirrored or is not defined.
Since:
1.5
compareTo
public int compareTo(Character anotherCharacter)
Compares two Character
objects numerically.
Specified by:
[compareTo](../../java/lang/Comparable.html#compareTo%28T%29)
in interface [Comparable](../../java/lang/Comparable.html "interface in java.lang")<[Character](../../java/lang/Character.html "class in java.lang")>
Parameters:
anotherCharacter
- the Character
to be compared.
Returns:
the value 0
if the argument Character
is equal to this Character
; a value less than 0
if this Character
is numerically less than the Character
argument; and a value greater than 0
if this Character
is numerically greater than the Character
argument (unsigned comparison). Note that this is strictly a numerical comparison; it is not locale-dependent.
Since:
1.2
reverseBytes
public static char reverseBytes(char ch)
Returns the value obtained by reversing the order of the bytes in the specified char value.
Returns:
the value obtained by reversing (or, equivalently, swapping) the bytes in the specified char value.
Since:
1.5
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