| Construct |
Matches |
| |
| Characters |
| x |
The character x
|
| \\ |
The backslash character |
|
\0n
|
The character with octal value 0n (0 <= n <= 7) |
|
\0nn
|
The character with octal value 0nn (0 <= n <= 7) |
|
\0mnn
|
The character with octal value 0mnn (0 <= m <= 3, 0 <= n <= 7) |
|
\xhh
|
The character with hexadecimal value 0xhh
|
|
\uhhhh
|
The character with hexadecimal value 0xhhhh
|
|
\x{h...h}
|
The character with hexadecimal value 0xh...h (Character.MIN_CODE_POINT <= 0xh...h <= Character.MAX_CODE_POINT) |
| \t |
The tab character ('\u0009') |
| \n |
The newline (line feed) character ('\u000A') |
| \r |
The carriage-return character ('\u000D') |
| \f |
The form-feed character ('\u000C') |
| \a |
The alert (bell) character ('\u0007') |
| \e |
The escape character ('\u001B') |
|
\cx
|
The control character corresponding to x
|
| |
| Character classes |
[abc] |
a, b, or c (simple class) |
[^abc] |
Any character except a, b, or c (negation) |
[a-zA-Z] |
a through z or A through Z, inclusive (range) |
[a-d[m-p]] |
a through d, or m through p: [a-dm-p] (union) |
[a-z&&[def]] |
d, e, or f (intersection) |
[a-z&&[^bc]] |
a through z, except for b and c: [ad-z] (subtraction) |
[a-z&&[^m-p]] |
a through z, and not m through p: [a-lq-z](subtraction) |
| |
| Predefined character classes |
| . |
Any character (may or may not match line terminators) |
| \d |
A digit: [0-9]
|
| \D |
A non-digit: [^0-9]
|
| \h |
A horizontal whitespace character: [ \t\xA0\u1680\u180e\u2000-\u200a\u202f\u205f\u3000]
|
| \H |
A non-horizontal whitespace character: [^\h]
|
| \s |
A whitespace character: [ \t\n\x0B\f\r]
|
| \S |
A non-whitespace character: [^\s]
|
| \v |
A vertical whitespace character: [\n\x0B\f\r\x85\u2028\u2029]
|
| \V |
A non-vertical whitespace character: [^\v]
|
| \w |
A word character: [a-zA-Z_0-9]
|
| \W |
A non-word character: [^\w]
|
| |
| POSIX character classes (US-ASCII only) |
\p{Lower} |
A lower-case alphabetic character: [a-z]
|
\p{Upper} |
An upper-case alphabetic character:[A-Z]
|
\p{ASCII} |
All ASCII:[\x00-\x7F]
|
\p{Alpha} |
An alphabetic character:[\p{Lower}\p{Upper}]
|
\p{Digit} |
A decimal digit: [0-9]
|
\p{Alnum} |
An alphanumeric character:[\p{Alpha}\p{Digit}]
|
\p{Punct} |
Punctuation: One of !"#$%&'()*+,-./:;<=>?@[\]^_`{|}~
|
\p{Graph} |
A visible character: [\p{Alnum}\p{Punct}]
|
\p{Print} |
A printable character: [\p{Graph}\x20]
|
\p{Blank} |
A space or a tab: [ \t]
|
\p{Cntrl} |
A control character: [\x00-\x1F\x7F]
|
\p{XDigit} |
A hexadecimal digit: [0-9a-fA-F]
|
\p{Space} |
A whitespace character: [ \t\n\x0B\f\r]
|
| |
| java.lang.Character classes (simple java character type) |
| \p{javaLowerCase} |
Equivalent to java.lang.Character.isLowerCase() |
| \p{javaUpperCase} |
Equivalent to java.lang.Character.isUpperCase() |
| \p{javaWhitespace} |
Equivalent to java.lang.Character.isWhitespace() |
| \p{javaMirrored} |
Equivalent to java.lang.Character.isMirrored() |
| |
| Classes for Unicode scripts, blocks, categories and binary properties |
\p{IsLatin} |
A Latin script character (script) |
\p{InGreek} |
A character in the Greek block (block) |
\p{Lu} |
An uppercase letter (category) |
\p{IsAlphabetic} |
An alphabetic character (binary property) |
\p{Sc} |
A currency symbol |
\P{InGreek} |
Any character except one in the Greek block (negation) |
[\p{L}&&[^\p{Lu}]] |
Any letter except an uppercase letter (subtraction) |
| |
| Boundary matchers |
| ^ |
The beginning of a line |
| $ |
The end of a line |
| \b |
A word boundary |
| \B |
A non-word boundary |
| \A |
The beginning of the input |
| \G |
The end of the previous match |
| \Z |
The end of the input but for the final terminator, if any |
| \z |
The end of the input |
| |
| Linebreak matcher |
| \R |
Any Unicode linebreak sequence, is equivalent to \u000D\u000A|[\u000A\u000B\u000C\u000D\u0085\u2028\u2029]
|
| |
| Greedy quantifiers |
|
X?
|
X, once or not at all |
|
X*
|
X, zero or more times |
|
X+
|
X, one or more times |
|
X{n}
|
X, exactly n times |
|
X{n,}
|
X, at least n times |
|
X{n,m}
|
X, at least n but not more than m times |
| |
| Reluctant quantifiers |
|
X??
|
X, once or not at all |
|
X*?
|
X, zero or more times |
|
X+?
|
X, one or more times |
|
X{n}?
|
X, exactly n times |
|
X{n,}?
|
X, at least n times |
|
X{n,m}?
|
X, at least n but not more than m times |
| |
| Possessive quantifiers |
|
X?+
|
X, once or not at all |
|
X*+
|
X, zero or more times |
|
X++
|
X, one or more times |
|
X{n}+
|
X, exactly n times |
|
X{n,}+
|
X, at least n times |
|
X{n,m}+
|
X, at least n but not more than m times |
| |
| Logical operators |
| XY |
X followed by Y
|
|
X|Y
|
Either X or Y
|
|
(X)
|
X, as a capturing group
|
| |
| Back references |
|
\n
|
Whatever the nth capturing group matched |
|
\k<name> |
Whatever the named-capturing group "name" matched |
| |
| Quotation |
| \ |
Nothing, but quotes the following character |
| \Q |
Nothing, but quotes all characters until \E
|
| \E |
Nothing, but ends quoting started by \Q
|
| |
| Special constructs (named-capturing and non-capturing) |
|
(?<name>X)
|
X, as a named-capturing group |
|
(?:X)
|
X, as a non-capturing group |
| (?idmsuxU-idmsuxU) |
Nothing, but turns match flags i d m s u x U on - off |
|
(?idmsux-idmsux:X) |
X, as a non-capturing group with the given flags i d m s u x on - off |
|
(?=X)
|
X, via zero-width positive lookahead |
|
(?!X)
|
X, via zero-width negative lookahead |
|
(?<=X)
|
X, via zero-width positive lookbehind |
|
(?<!X)
|
X, via zero-width negative lookbehind |
|
(?>X)
|
X, as an independent, non-capturing group |
