Der reguläre Ausdruck muss im Java Pattern Format angegeben werden. Am besten werden im regulären Ausdruck auch bereits Gruppen für den Dateinamen, die Zeilennummer und den Meldungstext definiert, die dann später im Groovy Skript einfach referenziert werden können.
Hier folgt ein Beispiel, das als Ausgangsbasis für den regulären Ausdruck verwendet werden kann: ^\s*(.*):(\d+):(.*):\s*(.*)$
Wenn dieser Ausdruck auf den Text file/name/relative/unix:42:MeineKategorie: Dies ist eine Beispielmeldung angewendet wird, dann wird ein Treffer gefunden. Anschließend sind die folgenden Gruppen verfügbar:
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 |
\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] |
\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] |
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 blocks and categories | |
\p{InGreek} | A character in the Greek block (simple block) |
\p{Lu} | An uppercase letter (simple category) |
\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 |
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 |
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 (non-capturing) | |
(?:X) | X, as a non-capturing group |
(?idmsux-idmsux) | Nothing, but turns match flags on - off |
(?idmsux-idmsux:X) | X, as a non-capturing group with the given flags 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 |
The backslash character ('\') serves to introduce escaped constructs, as defined in the table above, as well as to quote characters that otherwise would be interpreted as unescaped constructs. Thus the expression \\ matches a single backslash and \{ matches a left brace.
It is an error to use a backslash prior to any alphabetic character that does not denote an escaped construct; these are reserved for future extensions to the regular-expression language. A backslash may be used prior to a non-alphabetic character regardless of whether that character is part of an unescaped construct.
Backslashes within string literals in Java source code are interpreted
as required by the Java Language
Specification as either Unicode
escapes or other character
escapes. It is therefore necessary to double backslashes in string
literals that represent regular expressions to protect them from
interpretation by the Java bytecode compiler. The string literal
"\b", for example, matches a single backspace character when
interpreted as a regular expression, while "\\b" matches a
word boundary. The string literal "\(hello\)" is illegal
and leads to a compile-time error; in order to match the string
(hello) the string literal "\\(hello\\)"
must be used.
Character classes may appear within other character classes, and
may be composed by the union operator (implicit) and the intersection
operator (&&).
The union operator denotes a class that contains every character that is
in at least one of its operand classes. The intersection operator
denotes a class that contains every character that is in both of its
operand classes.
The precedence of character-class operators is as follows, from
highest to lowest:
Note that a different set of metacharacters are in effect inside
a character class than outside a character class. For instance, the
regular expression . loses its special meaning inside a
character class, while the expression - becomes a range
forming metacharacter.
A line terminator is a one- or two-character sequence that marks
the end of a line of the input character sequence. The following are
recognized as line terminators:
If The regular expression . matches any character except a line
terminator unless the By default, the regular expressions ^ and $ ignore
line terminators and only match at the beginning and the end, respectively,
of the entire input sequence. If Capturing groups are numbered by counting their opening parentheses from
left to right. In the expression ((A)(B(C))), for example, there
are four such groups: Group zero always stands for the entire expression.
Capturing groups are so named because, during a match, each subsequence
of the input sequence that matches such a group is saved. The captured
subsequence may be used later in the expression, via a back reference, and
may also be retrieved from the matcher once the match operation is complete.
The captured input associated with a group is always the subsequence
that the group most recently matched. If a group is evaluated a second time
because of quantification then its previously-captured value, if any, will
be retained if the second evaluation fails. Matching the string
"aba" against the expression (a(b)?)+, for example, leaves
group two set to "b". All captured input is discarded at the
beginning of each match.
Groups beginning with (? are pure, non-capturing groups
that do not capture text and do not count towards the group total.
This class is in conformance with Level 1 of Unicode Technical
Standard #18: Unicode Regular Expression Guidelines, plus RL2.1
Canonical Equivalents.
Unicode escape sequences such as \u2014 in Java source code
are processed as described in �3.3
of the Java Language Specification. Such escape sequences are also
implemented directly by the regular-expression parser so that Unicode
escapes can be used in expressions that are read from files or from the
keyboard. Thus the strings "\u2014" and "\\u2014",
while not equal, compile into the same pattern, which matches the character
with hexadecimal value 0x2014.
Unicode blocks and categories are written with the
\p and \P constructs as in
Perl. \p{prop} matches if the input has the
property prop, while \P{prop} does not match if
the input has that property. Blocks are specified with the prefix
In, as in InMongolian. Categories may be specified with
the optional prefix Is: Both \p{L} and \p{IsL}
denote the category of Unicode letters. Blocks and categories can be used
both inside and outside of a character class.
The supported categories are those of
The Unicode Standard in the version specified by the
Categories that behave like the java.lang.Character
boolean ismethodname methods (except for the deprecated ones) are
available through the same \p{prop} syntax where
the specified property has the name javamethodname.
Character Classes
1
Literal escape
\x 2
Grouping
[...] 3
Range
a-z 4
Union
[a-e][i-u] 5
Intersection
[a-z&&[aeiou]] Line terminators
UNIX_LINES
mode is activated, then the only line terminators
recognized are newline characters.
DOTALL
flag is specified.
MULTILINE
mode is activated then
^ matches at the beginning of input and after any line terminator
except at the end of input. When in MULTILINE
mode $
matches just before a line terminator or the end of the input sequence.
Groups and capturing
1
((A)(B(C))) 2
(A) 3
(B(C)) 4
(C) Unicode support
Character
class. The category names are those
defined in the Standard, both normative and informative.
The block names supported by Pattern
are the valid block names
accepted and defined by
UnicodeBlock.forName
.