JAVA中正则表达式元字符

Summary of regular-expression constructs

ConstructMatches CharactersxThe character x\\The backslash character\0nThe character with octal value 0n (0 <= n <= 7)\0nnThe character with octal value 0nn (0 <= n <= 7)\0mnnThe character with octal value 0mnn (0 <= m <= 3, 0 <= n <= 7)\xhhThe character with hexadecimal value 0xhh\uhhhhThe 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)\tThe tab character ('\u0009')\nThe newline (line feed) character ('\u000A')\rThe carriage-return character ('\u000D')\fThe form-feed character ('\u000C')\aThe alert (bell) character ('\u0007')\eThe escape character ('\u001B')\cxThe 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)\dA digit: [0-9]\DA non-digit: [^0-9]\hA horizontal whitespace character: [ \t\xA0\u1680\u180e\u2000-\u200a\u202f\u205f\u3000]\HA non-horizontal whitespace character: [^\h]\sA whitespace character: [ \t\n\x0B\f\r]\SA non-whitespace character: [^\s]\vA vertical whitespace character: [\n\x0B\f\r\x85\u2028\u2029]\VA non-vertical whitespace character: [^\v]\wA word character: [a-zA-Z_0-9]\WA 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\bA word boundary\BA non-word boundary\AThe beginning of the input\GThe end of the previous match\ZThe end of the input but for the final terminator, if any\zThe end of the input Linebreak matcher\RAny Unicode linebreak sequence, is equivalent to \u000D\u000A|[\u000A\u000B\u000C\u000D\u0085\u2028\u2029] Greedy quantifiersX?X, once or not at allX*X, zero or more timesX+X, one or more timesX{n}X, exactly n timesX{n,}X, at least n timesX{n,m}X, at least n but not more than m times Reluctant quantifiersX??X, once or not at allX*?X, zero or more timesX+?X, one or more timesX{n}?X, exactly n timesX{n,}?X, at least n timesX{n,m}?X, at least n but not more than m times Possessive quantifiersX?+X, once or not at allX*+X, zero or more timesX++X, one or more timesX{n}+X, exactly n timesX{n,}+X, at least n timesX{n,m}+X, at least n but not more than m times Logical operatorsXYX followed by YX|YEither X or Y(X)X, as a capturing group Back references\nWhatever the n^th capturing group matched\k<name>Whatever the named-capturing group "name" matched Quotation\Nothing, but quotes the following character\QNothing, but quotes all characters until \E\ENothing, 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