Regular expressions are used to classify assets and tie them to data elements depending on whether the sample data of an asset matches with the regular expressions defined on data elements.
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 (’007`)
\e The escape character ('\u001B)
\cx The control character corresponding to x
[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)
. Any character (may or may not match line terminators)
\d A digit: [0-9]
\\D A non-digit: [^0-9]
\s A whitespace character: [ \t\n\x0B\f\r]
\\S A non-whitespace character: [^\s]
\w A word character: [a-zA-Z_0-9]
\W A non-word character: [^\w]
\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]
\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)
^ 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
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
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
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
XY X followed by Y
X|Y Either X or Y
(X) X, as a capturing group
\n Whatever the nth capturing group matched
\k<name> Whatever the named-capturing group name matched
\ Nothing, but quotes the following character
\Q Nothing, but quotes all characters until \E
\E Nothing, but ends quoting started by \Q
(?<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