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/*
* Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package com.ingerlflori.util.regex;
import java.text.Normalizer;
import java.util.Locale;
import java.util.Iterator;
import java.util.Map;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Arrays;
import java.util.NoSuchElementException;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.Stack;
import java.util.Vector;
import java.util.function.Predicate;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
/**
* A compiled representation of a regular expression.
*
*
* A regular expression, specified as a string, must first be compiled into an
* instance of this class. The resulting pattern can then be used to create a
* {@link Matcher} object that can match arbitrary
* {@linkplain java.lang.CharSequence character sequences} against the regular
* expression. All of the state involved in performing a match resides in the
* matcher, so many matchers can share the same pattern.
*
*
* A typical invocation sequence is thus
*
*
*
*
* Pattern p = Pattern.{@link #compile compile}("a*b");
* Matcher m = p.{@link #matcher matcher}("aaaaab");
* boolean b = m.{@link Matcher#matches matches}();
*
*
*
*
*
* A {@link #matches matches} method is defined by this class as a convenience
* for when a regular expression is used just once. This method compiles an
* expression and matches an input sequence against it in a single invocation.
* The statement
*
*
*
*
* boolean b = Pattern.matches("a*b", "aaaaab");
*
*
*
*
* is equivalent to the three statements above, though for repeated matches it
* is less efficient since it does not allow the compiled pattern to be reused.
*
*
* Instances of this class are immutable and are safe for use by multiple
* concurrent threads. Instances of the {@link Matcher} class are not safe for
* such use.
*
*
*
Summary of regular-expression constructs
*
*
*
*
* 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 ({@link java.lang.Character#MIN_CODE_POINT
* Character.MIN_CODE_POINT} <= 0xh...h
* <= {@link java.lang.Character#MAX_CODE_POINT
* 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
*
*
*
* {@code [abc]}
* {@code a}, {@code b}, or {@code c} (simple class)
*
*
* {@code [^abc]}
* Any character except {@code a}, {@code b}, or {@code c}
* (negation)
*
*
* {@code [a-zA-Z]}
* {@code a} through {@code z} or {@code A} through
* {@code Z}, inclusive (range)
*
*
* {@code [a-d[m-p]]}
* {@code a} through {@code d}, or {@code m} through
* {@code p}: {@code [a-dm-p]} (union)
*
*
* {@code [a-z&&[def]]}
* {@code d}, {@code e}, or {@code f} (intersection)
*
*
* {@code [a-z&&[^bc]]}
* {@code a} through {@code z}, except for {@code b} and
* {@code c}: {@code [ad-z]} (subtraction)
*
*
* {@code [a-z&&[^m-p]]}
* {@code a} through {@code z}, and not {@code m} through
* {@code p}: {@code [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)
*
*
*
*
* {@code \p{Lower}}
* A lower-case alphabetic character: {@code [a-z]}
*
*
* {@code \p{Upper}}
* An upper-case alphabetic character:{@code [A-Z]}
*
*
* {@code \p{ASCII}}
* All ASCII:{@code [\x00-\x7F]}
*
*
* {@code \p{Alpha}}
* An alphabetic character:{@code [\p{Lower}\p{Upper}]}
*
*
*
* {@code \p{Digit}}
* A decimal digit: {@code [0-9]}
*
*
* {@code \p{Alnum}}
* An alphanumeric character:{@code [\p{Alpha}\p{Digit}]}
*
*
*
* {@code \p{Punct}}
* Punctuation: One of {@code !"#$%&'()*+,-./:;
* <=>?@[\]^_`{|}~}
*
*
*
* {@code \p{Graph}}
* A visible character: {@code [\p{Alnum}\p{Punct}]}
*
*
* {@code \p{Print}}
* A printable character: {@code [\p{Graph}\x20]}
*
*
* {@code \p{Blank}}
* A space or a tab: {@code [ \t]}
*
*
* {@code \p{Cntrl}}
* A control character: {@code [\x00-\x1F\x7F]}
*
*
* {@code \p{XDigit}}
* A hexadecimal digit: {@code [0-9a-fA-F]}
*
*
* {@code \p{Space}}
* A whitespace character: {@code [ \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
*
*
* {@code \p{IsLatin}}
* A Latin script character (
* script)
*
*
* {@code \p{InGreek}}
* A character in the Greek block (
* block)
*
*
* {@code \p{Lu}}
* An uppercase letter (category)
*
*
* {@code \p{IsAlphabetic}}
* An alphabetic character (binary
* property)
*
*
* {@code \p{Sc}}
* A currency symbol
*
*
* {@code \P{InGreek}}
* Any character except one in the Greek block (negation)
*
*
*
* {@code [\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
*
*
*
*
*
*
*
*
* Recursive expressions
*
*
*
* (?name)
* Matches the pattern of the
* named-capturing group "name" again.
*
*
* (?n)
*
* Matches the pattern given by the nth
* group again. n must be greater than 0.
*
*
*
*
*
* Conditional expressions
*
*
*
* (?(name)Y|N)
* If the capture stack of the
* named-capturing group "name" isn't empty, Y is
* matched. Otherwise the optional pattern N is matched.
*
*
* (?(n
* )Y|N)
* If the capture stack of the nth group
* isn't empty, Y is matched. Otherwise the optional pattern N is matched.
*
*
* (?(COND)Y|N)
* If the pattern (?=COND) can be matched, Y is matched.
* Otherwise the optional pattern N is matched.
*
*
*
*
*
*
* Special constructs (named-capturing and
* non-capturing)
*
*
*
*
* (?<name>X)
* X, as a named-capturing group
*
*
*
* (?<-name>X)
* After a successfull match of X, one capture is
* popped from the capture stack of the named-capturing
* group "name". If the capture stack is empty, the search backtracks.
*
*
* (?<-n
* >X)
* After a successfull match of X, one capture is
* popped from the capture stack of the nth group. If the
* capture stack is empty, the search backtracks.
*
*
* (?: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 atomic, non-capturing group
*
*
*
*
*
*
* Backslashes, escapes, and quoting
*
*
* 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 (section 3.3) or other character escapes (section 3.10.6) 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
*
*
* 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:
*
*
*
*
* 1
* Literal escape
* \x
*
*
* 2
* Grouping
* [...]
*
*
* 3
* Range
* a-z
*
*
* 4
* Union
* [a-e][i-u]
*
*
* 5
* Intersection
* {@code [a-z&&[aeiou]]}
*
*
*
*
*
* 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.
*
*
Line terminators
*
*
* 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:
*
*
*
* - A newline (line feed) character ('\n'),
*
*
- A carriage-return character followed immediately by a newline
* character ("\r\n"),
*
*
- A standalone carriage-return character ('\r'),
*
*
- A next-line character ('\u0085'),
*
*
- A line-separator character ('\u2028'), or
*
*
- A paragraph-separator character ('\u2029).
*
*
*
* If {@link #UNIX_LINES} mode is activated, then the only line terminators
* recognized are newline characters.
*
*
* The regular expression . matches any character except a line
* terminator unless the {@link #DOTALL} flag is specified.
*
*
* 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 {@link #MULTILINE} mode is activated then
* ^ matches at the beginning of input and after any line terminator
* except at the end of input. When in {@link #MULTILINE} mode $
* matches just before a line terminator or the end of the input sequence.
*
*
Groups and capturing
*
* Group number
*
* 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:
*
*
*
*
*
* 1
* ((A)(B(C)))
*
*
* 2
* (A)
*
*
* 3
* (B(C))
*
*
* 4
* (C)
*
*
*
*
*
* 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.
*
*
Group name
*
* A capturing group can also be assigned a "name", a
* named-capturing group, and then be back-referenced later by the
* "name". Group names are composed of the following characters. The first
* character must be a letter.
*
*
* - The uppercase letters 'A' through 'Z' (
* '\u0041' through '\u005a'),
*
- The lowercase letters 'a' through 'z' (
* '\u0061' through '\u007a'),
*
- The digits '0' through '9' ('\u0030'
* through '\u0039'),
*
*
*
* A named-capturing group is still numbered as described in
* Group number.
*
*
* 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 either pure, non-capturing
* groups that do not capture text and do not count towards the group total, or
* named-capturing group.
*
*
Unicode support
*
*
* This class is in conformance with Level 1 of
* Unicode Technical Standard
* #18: Unicode Regular Expression, plus RL2.1 Canonical Equivalents.
*
* Unicode escape sequences such as \u2014 in Java source
* code are processed as described in section 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.
*
* A Unicode character can also be represented in a regular-expression by using
* its Hex notation(hexadecimal code point value) directly as described
* in construct \x{...}, for example a supplementary character
* U+2011F can be specified as \x{2011F}, instead of two
* consecutive Unicode escape sequences of the surrogate pair
* \uD840\uDD1F.
*
* Unicode scripts, blocks, categories and binary properties 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.
*
* Scripts, blocks, categories and binary properties can be used both inside and
* outside of a character class.
*
*
* Scripts are specified either with the prefix
* {@code Is}, as in {@code IsHiragana}, or by using the {@code script} keyword
* (or its short form {@code sc})as in {@code script=Hiragana} or
* {@code sc=Hiragana}.
*
* The script names supported by Pattern are the valid script names
* accepted and defined by
* {@link java.lang.Character.UnicodeScript#forName(String)
* UnicodeScript.forName}.
*
*
* Blocks are specified with the prefix {@code In}, as
* in {@code InMongolian}, or by using the keyword {@code block} (or its short
* form {@code blk}) as in {@code block=Mongolian} or {@code blk=Mongolian}.
*
* The block names supported by Pattern are the valid block names
* accepted and defined by
* {@link java.lang.Character.UnicodeBlock#forName(String) UnicodeBlock.forName}
* .
*
*
* Categories may be specified with the optional prefix
* {@code Is}: Both {@code \p{L}} and {@code \p{IsL}} denote the category of
* Unicode letters. Same as scripts and blocks, categories can also be specified
* by using the keyword {@code general_category} (or its short form {@code gc})
* as in {@code general_category=Lu} or {@code gc=Lu}.
*
* The supported categories are those of
* The
* Unicode Standard in the version specified by the
* {@link java.lang.Character Character} class. The category names are those
* defined in the Standard, both normative and informative.
*
*
* Binary properties are specified with the prefix
* {@code Is}, as in {@code IsAlphabetic}. The supported binary properties by
* Pattern are
*
* - Alphabetic
*
- Ideographic
*
- Letter
*
- Lowercase
*
- Uppercase
*
- Titlecase
*
- Punctuation
*
- Control
*
- White_Space
*
- Digit
*
- Hex_Digit
*
- Join_Control
*
- Noncharacter_Code_Point
*
- Assigned
*
*
* The following Predefined Character classes and POSIX character
* classes are in conformance with the recommendation of Annex C:
* Compatibility Properties of
* Unicode Regular
* Expression , when {@link #UNICODE_CHARACTER_CLASS} flag is specified.
*
*
*
* Classes
* Matches
*
*
* \p{Lower}
* A lowercase character:\p{IsLowercase}
*
*
* \p{Upper}
* An uppercase character:\p{IsUppercase}
*
*
* \p{ASCII}
* All ASCII:[\x00-\x7F]
*
*
* \p{Alpha}
* An alphabetic character:\p{IsAlphabetic}
*
*
* \p{Digit}
* A decimal digit character:p{IsDigit}
*
*
* \p{Alnum}
* An alphanumeric character:[\p{IsAlphabetic}\p{IsDigit}]
*
*
* \p{Punct}
* A punctuation character:p{IsPunctuation}
*
*
* \p{Graph}
* A visible character:
* [^\p{IsWhite_Space}\p{gc=Cc}\p{gc=Cs}\p{gc=Cn}]
*
*
* \p{Print}
* A printable character: {@code [\p{Graph}\p{Blank}&&[^\p{Cntrl}]]}
*
*
* \p{Blank}
* A space or a tab:
* {@code [\p{IsWhite_Space}&&[^\p{gc=Zl}\p{gc=Zp}\x0a\x0b\x0c\x0d\x85]]}
*
*
* \p{Cntrl}
* A control character: \p{gc=Cc}
*
*
* \p{XDigit}
* A hexadecimal digit: [\p{gc=Nd}\p{IsHex_Digit}]
*
*
* \p{Space}
* A whitespace character:\p{IsWhite_Space}
*
*
* \d
* A digit: \p{IsDigit}
*
*
* \D
* A non-digit: [^\d]
*
*
* \s
* A whitespace character: \p{IsWhite_Space}
*
*
* \S
* A non-whitespace character: [^\s]
*
*
* \w
* A word character:
* [\p{Alpha}\p{gc=Mn}\p{gc=Me}\p{gc=Mc}\p{Digit}\p{gc=Pc}\p{IsJoin_Control}]
*
*
*
* \W
* A non-word character: [^\w]
*
*
* Comparison to Perl 5
*
*
* The Pattern engine performs traditional NFA-based matching with
* ordered alternation as occurs in Perl 5.
*
*
* Perl constructs not supported by this class:
*
*
*
* -
*
* Predefined character classes (Unicode character)
*
* \X Match Unicode
*
* extended grapheme cluster
*
*
*
* -
*
* The backreference constructs, \g{n} for the n
* thcapturing group and \g{name
* } for named-capturing group.
*
*
*
* -
*
* The named character construct, \N{name} for a
* Unicode character by its name.
*
*
*
* -
*
* The conditional constructs (?(condition)X
* ) and (?(condition)X|
* Y),
*
*
*
* -
*
* The embedded code constructs (?{code}) and
* (??{code}),
*
*
*
* -
*
* The embedded comment syntax (?#comment), and
*
*
*
* -
*
* The preprocessing operations \l \u, \L, and
* \U.
*
*
*
*
*
*
* Constructs supported by this class but not by Perl:
*
*
*
*
* -
*
* Character-class union and intersection as described above.
*
*
*
*
*
*
* Notable differences from Perl:
*
*
*
*
* -
*
* In Perl, \1 through \9 are always interpreted as back
* references; a backslash-escaped number greater than 9 is treated as
* a back reference if at least that many subexpressions exist, otherwise it is
* interpreted, if possible, as an octal escape. In this class octal escapes
* must always begin with a zero. In this class, \1 through \9
* are always interpreted as back references, and a larger number is accepted as
* a back reference if at least that many subexpressions exist at that point in
* the regular expression, otherwise the parser will drop digits until the
* number is smaller or equal to the existing number of groups or it is one
* digit.
*
*
*
* -
*
* Perl uses the g flag to request a match that resumes where the last
* match left off. This functionality is provided implicitly by the
* {@link Matcher} class: Repeated invocations of the {@link Matcher#find find}
* method will resume where the last match left off, unless the matcher is
* reset.
*
*
*
* -
*
* In Perl, embedded flags at the top level of an expression affect the whole
* expression. In this class, embedded flags always take effect at the point at
* which they appear, whether they are at the top level or within a group; in
* the latter case, flags are restored at the end of the group just as in Perl.
*
*
*
*
*
*
*
* For a more precise description of the behavior of regular expression
* constructs, please see
* Mastering Regular
* Expressions, 3nd Edition, Jeffrey E. F. Friedl, O'Reilly and Associates,
* 2006.
*
*
* @see java.lang.String#split(String, int)
* @see java.lang.String#split(String)
*
* @author Mike McCloskey
* @author Mark Reinhold
* @author JSR-51 Expert Group
* @since 1.4
*/
public final class Pattern implements java.io.Serializable {
/**
* Regular expression modifier values. Instead of being passed as arguments,
* they can also be passed as inline modifiers. For example, the following
* statements have the same effect.
*
*
* RegExp r1 = RegExp.compile("abc", Pattern.I | Pattern.M);
* RegExp r2 = RegExp.compile("(?im)abc", 0);
*
*
* The flags are duplicated so that the familiar Perl match flag names are
* available.
*/
/**
* Enables Unix lines mode.
*
*
* In this mode, only the '\n' line terminator is recognized in the
* behavior of ., ^, and $.
*
*
* Unix lines mode can also be enabled via the embedded flag
* expression (?d).
*/
public static final int UNIX_LINES = 0x01;
/**
* Enables case-insensitive matching.
*
*
* By default, case-insensitive matching assumes that only characters in the
* US-ASCII charset are being matched. Unicode-aware case-insensitive
* matching can be enabled by specifying the {@link #UNICODE_CASE} flag in
* conjunction with this flag.
*
*
* Case-insensitive matching can also be enabled via the embedded flag
* expression (?i).
*
*
* Specifying this flag may impose a slight performance penalty.
*
*/
public static final int CASE_INSENSITIVE = 0x02;
/**
* Permits whitespace and comments in pattern.
*
*
* In this mode, whitespace is ignored, and embedded comments starting with
* # are ignored until the end of a line.
*
*
* Comments mode can also be enabled via the embedded flag expression
* (?x).
*/
public static final int COMMENTS = 0x04;
/**
* Enables multiline mode.
*
*
* In multiline mode the expressions ^ and $ match just
* after or just before, respectively, a line terminator or the end of the
* input sequence. By default these expressions only match at the beginning
* and the end of the entire input sequence.
*
*
* Multiline mode can also be enabled via the embedded flag expression
* (?m).
*
*/
public static final int MULTILINE = 0x08;
/**
* Enables literal parsing of the pattern.
*
*
* When this flag is specified then the input string that specifies the
* pattern is treated as a sequence of literal characters. Metacharacters or
* escape sequences in the input sequence will be given no special meaning.
*
*
* The flags CASE_INSENSITIVE and UNICODE_CASE retain their impact on
* matching when used in conjunction with this flag. The other flags become
* superfluous.
*
*
* There is no embedded flag character for enabling literal parsing.
*
* @since 1.5
*/
public static final int LITERAL = 0x10;
/**
* Enables dotall mode.
*
*
* In dotall mode, the expression . matches any character,
* including a line terminator. By default this expression does not match
* line terminators.
*
*
* Dotall mode can also be enabled via the embedded flag expression
* (?s). (The s is a mnemonic for "single-line" mode,
* which is what this is called in Perl.)
*
*/
public static final int DOTALL = 0x20;
/**
* Enables Unicode-aware case folding.
*
*
* When this flag is specified then case-insensitive matching, when enabled
* by the {@link #CASE_INSENSITIVE} flag, is done in a manner consistent
* with the Unicode Standard. By default, case-insensitive matching assumes
* that only characters in the US-ASCII charset are being matched.
*
*
* Unicode-aware case folding can also be enabled via the embedded flag
* expression (?u).
*
*
* Specifying this flag may impose a performance penalty.
*
*/
public static final int UNICODE_CASE = 0x40;
/**
* Enables canonical equivalence.
*
*
* When this flag is specified then two characters will be considered to
* match if, and only if, their full canonical decompositions match. The
* expression "a\u030A", for example, will match the string
* "\u00E5" when this flag is specified. By default, matching
* does not take canonical equivalence into account.
*
*
* There is no embedded flag character for enabling canonical equivalence.
*
*
* Specifying this flag may impose a performance penalty.
*
*/
public static final int CANON_EQ = 0x80;
/**
* Enables the Unicode version of Predefined character classes and
* POSIX character classes.
*
*
* When this flag is specified then the (US-ASCII only) Predefined
* character classes and POSIX character classes are in
* conformance with
* Unicode Technical
* Standard #18: Unicode Regular Expression Annex C:
* Compatibility Properties.
*
* The UNICODE_CHARACTER_CLASS mode can also be enabled via the embedded
* flag expression (?U).
*
* The flag implies UNICODE_CASE, that is, it enables Unicode-aware case
* folding.
*
* Specifying this flag may impose a performance penalty.
*
*
* @since 1.7
*/
public static final int UNICODE_CHARACTER_CLASS = 0x100;
/*
* Pattern has only two serialized components: The pattern string and the
* flags, which are all that is needed to recompile the pattern when it is
* deserialized.
*/
/** use serialVersionUID from Merlin b59 for interoperability */
private static final long serialVersionUID = 5073258162644648461L;
/**
* The original regular-expression pattern string.
*
* @serial
*/
private String pattern;
/**
* The original pattern flags.
*
* @serial
*/
private int flags;
/**
* Boolean indicating this Pattern is compiled; this is necessary in order
* to lazily compile deserialized Patterns.
*/
private transient volatile boolean compiled = false;
/**
* The normalized pattern string.
*/
private transient String normalizedPattern;
/**
* The starting point of state machine for the find operation. This allows a
* match to start anywhere in the input.
*/
transient Node root;
/**
* The root of object tree for a match operation. The pattern is matched at
* the beginning. This may include a find that uses BnM or a First node.
*/
transient Node matchRoot;
/**
* Temporary storage used by parsing pattern slice.
*/
transient int[] buffer;
/**
* Map the "name" of the "named capturing group" to its group id node.
*/
transient volatile Map namedGroups;
private transient ArrayList groupHeadAndTailNodes;
/**
* Temporary null terminated code point array used by pattern compiling.
*/
private transient int[] temp;
/**
* The number of capturing groups in this Pattern. Used by matchers to
* allocate storage needed to perform a match.
*/
transient int capturingGroupCount;
/**
* The local variable count used by parsing tree. Used by matchers to
* allocate storage needed to perform a match.
*/
transient int localCount;
/**
* Index into the pattern string that keeps track of how much has been
* parsed.
*/
private transient int cursor;
/**
* Holds the length of the pattern string.
*/
private transient int patternLength;
/**
* If the Start node might possibly match supplementary characters. It is
* set to true during compiling if (1) There is supplementary char in
* pattern, or (2) There is complement node of Category or Block
*/
private transient boolean hasSupplementary;
/**
* Compiles the given regular expression into a pattern.
*
* @param regex
* The expression to be compiled
* @return the given regular expression compiled into a pattern
* @throws PatternSyntaxException
* If the expression's syntax is invalid
*/
public static Pattern compile(String regex) {
return new Pattern(regex, 0);
}
/**
* Compiles the given regular expression into a pattern with the given
* flags.
*
* @param regex
* The expression to be compiled
*
* @param flags
* Match flags, a bit mask that may include
* {@link #CASE_INSENSITIVE}, {@link #MULTILINE}, {@link #DOTALL}
* , {@link #UNICODE_CASE}, {@link #CANON_EQ},
* {@link #UNIX_LINES}, {@link #LITERAL},
* {@link #UNICODE_CHARACTER_CLASS} and {@link #COMMENTS}
*
* @return the given regular expression compiled into a pattern with the
* given flags
* @throws IllegalArgumentException
* If bit values other than those corresponding to the defined
* match flags are set in flags
*
* @throws PatternSyntaxException
* If the expression's syntax is invalid
*/
public static Pattern compile(String regex, int flags) {
return new Pattern(regex, flags);
}
/**
* Returns the regular expression from which this pattern was compiled.
*
* @return The source of this pattern
*/
public String pattern() {
return pattern;
}
/**
*
* Returns the string representation of this pattern. This is the regular
* expression from which this pattern was compiled.
*
*
* @return The string representation of this pattern
* @since 1.5
*/
public String toString() {
return pattern;
}
/**
* Creates a matcher that will match the given input against this pattern.
*
* @param input
* The character sequence to be matched
*
* @return A new matcher for this pattern
*/
public Matcher matcher(CharSequence input) {
if (!compiled) {
synchronized (this) {
if (!compiled)
compile();
}
}
Matcher m = new Matcher(this, input);
return m;
}
/**
* Returns this pattern's match flags.
*
* @return The match flags specified when this pattern was compiled
*/
public int flags() {
return flags;
}
/**
* Compiles the given regular expression and attempts to match the given
* input against it.
*
*
* An invocation of this convenience method of the form
*
*
*
*
* Pattern.matches(regex, input);
*
*
*
*
* behaves in exactly the same way as the expression
*
*
*
*
* Pattern.compile(regex).matcher(input).matches()
*
*
*
*
*
* If a pattern is to be used multiple times, compiling it once and reusing
* it will be more efficient than invoking this method each time.
*
*
* @param regex
* The expression to be compiled
*
* @param input
* The character sequence to be matched
* @return whether or not the regular expression matches on the input
* @throws PatternSyntaxException
* If the expression's syntax is invalid
*/
public static boolean matches(String regex, CharSequence input) {
Pattern p = Pattern.compile(regex);
Matcher m = p.matcher(input);
return m.matches();
}
/**
* Splits the given input sequence around matches of this pattern.
*
*
* The array returned by this method contains each substring of the input
* sequence that is terminated by another subsequence that matches this
* pattern or is terminated by the end of the input sequence. The substrings
* in the array are in the order in which they occur in the input. If this
* pattern does not match any subsequence of the input then the resulting
* array has just one element, namely the input sequence in string form.
*
*
* When there is a positive-width match at the beginning of the input
* sequence then an empty leading substring is included at the beginning of
* the resulting array. A zero-width match at the beginning however never
* produces such empty leading substring.
*
*
* The limit parameter controls the number of times the pattern is
* applied and therefore affects the length of the resulting array. If the
* limit n is greater than zero then the pattern will be applied at
* most n - 1 times, the array's length will be no greater
* than n, and the array's last entry will contain all input beyond
* the last matched delimiter. If n is non-positive then the pattern
* will be applied as many times as possible and the array can have any
* length. If n is zero then the pattern will be applied as many
* times as possible, the array can have any length, and trailing empty
* strings will be discarded.
*
*
* The input "boo:and:foo", for example, yields the following
* results with these parameters:
*
*
*
*
* Regex
* Limit
* Result
*
*
* :
* 2
* { "boo", "and:foo" }
*
*
* :
* 5
* { "boo", "and", "foo" }
*
*
* :
* -2
* { "boo", "and", "foo" }
*
*
* o
* 5
* { "b", "", ":and:f", "", "" }
*
*
* o
* -2
* { "b", "", ":and:f", "", "" }
*
*
* o
* 0
* { "b", "", ":and:f" }
*
*
*
*
* @param input
* The character sequence to be split
*
* @param limit
* The result threshold, as described above
*
* @return The array of strings computed by splitting the input around
* matches of this pattern
*/
public String[] split(CharSequence input, int limit) {
int index = 0;
boolean matchLimited = limit > 0;
ArrayList matchList = new ArrayList();
Matcher m = matcher(input);
// Add segments before each match found
while (m.find()) {
if (!matchLimited || matchList.size() < limit - 1) {
if (index == 0 && index == m.start() && m.start() == m.end()) {
// no empty leading substring included for zero-width match
// at the beginning of the input char sequence.
continue;
}
String match = input.subSequence(index, m.start()).toString();
matchList.add(match);
index = m.end();
} else if (matchList.size() == limit - 1) { // last one
String match = input.subSequence(index, input.length()).toString();
matchList.add(match);
index = m.end();
}
}
// If no match was found, return this
if (index == 0)
return new String[] { input.toString() };
// Add remaining segment
if (!matchLimited || matchList.size() < limit)
matchList.add(input.subSequence(index, input.length()).toString());
// Construct result
int resultSize = matchList.size();
if (limit == 0)
while (resultSize > 0 && matchList.get(resultSize - 1).equals(""))
resultSize--;
String[] result = new String[resultSize];
return matchList.subList(0, resultSize).toArray(result);
}
/**
* Splits the given input sequence around matches of this pattern.
*
*
* This method works as if by invoking the two-argument
* {@link #split(java.lang.CharSequence, int) split} method with the given
* input sequence and a limit argument of zero. Trailing empty strings are
* therefore not included in the resulting array.
*
*
*
* The input "boo:and:foo", for example, yields the following
* results with these expressions:
*
*
*
*
* Regex
* Result
*
*
* :
* { "boo", "and", "foo" }
*
*
* o
* { "b", "", ":and:f" }
*
*
*
*
*
* @param input
* The character sequence to be split
*
* @return The array of strings computed by splitting the input around
* matches of this pattern
*/
public String[] split(CharSequence input) {
return split(input, 0);
}
/**
* Returns a literal pattern String for the specified
* String.
*
*
* This method produces a String that can be used to create a
* Pattern that would match the string s as if it
* were a literal pattern.
*
* Metacharacters or escape sequences in the input sequence will be given no
* special meaning.
*
* @param s
* The string to be literalized
* @return A literal string replacement
* @since 1.5
*/
public static String quote(String s) {
int slashEIndex = s.indexOf("\\E");
if (slashEIndex == -1)
return "\\Q" + s + "\\E";
StringBuilder sb = new StringBuilder(s.length() * 2);
sb.append("\\Q");
slashEIndex = 0;
int current = 0;
while ((slashEIndex = s.indexOf("\\E", current)) != -1) {
sb.append(s.substring(current, slashEIndex));
current = slashEIndex + 2;
sb.append("\\E\\\\E\\Q");
}
sb.append(s.substring(current, s.length()));
sb.append("\\E");
return sb.toString();
}
/**
* Recompile the Pattern instance from a stream. The original pattern string
* is read in and the object tree is recompiled from it.
*/
private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
// Read in all fields
s.defaultReadObject();
// Initialize counts
capturingGroupCount = 1;
localCount = 0;
// if length > 0, the Pattern is lazily compiled
compiled = false;
if (pattern.length() == 0) {
root = new Start(lastAccept);
matchRoot = lastAccept;
compiled = true;
}
}
/**
* This private constructor is used to create all Patterns. The pattern
* string and match flags are all that is needed to completely describe a
* Pattern. An empty pattern string results in an object tree with only a
* Start node and a LastNode node.
*/
private Pattern(String p, int f) {
pattern = p;
flags = f;
// to use UNICODE_CASE if UNICODE_CHARACTER_CLASS present
if ((flags & UNICODE_CHARACTER_CLASS) != 0)
flags |= UNICODE_CASE;
// Reset group index count
capturingGroupCount = 1;
localCount = 0;
if (pattern.length() > 0) {
compile();
} else {
root = new Start(lastAccept);
matchRoot = lastAccept;
}
}
/**
* The pattern is converted to normalizedD form and then a pure group is
* constructed to match canonical equivalences of the characters.
*/
private void normalize() {
boolean inCharClass = false;
int lastCodePoint = -1;
// Convert pattern into normalizedD form
normalizedPattern = Normalizer.normalize(pattern, Normalizer.Form.NFD);
patternLength = normalizedPattern.length();
// Modify pattern to match canonical equivalences
StringBuilder newPattern = new StringBuilder(patternLength);
for (int i = 0; i < patternLength;) {
int c = normalizedPattern.codePointAt(i);
StringBuilder sequenceBuffer;
if ((Character.getType(c) == Character.NON_SPACING_MARK) && (lastCodePoint != -1)) {
sequenceBuffer = new StringBuilder();
sequenceBuffer.appendCodePoint(lastCodePoint);
sequenceBuffer.appendCodePoint(c);
while (Character.getType(c) == Character.NON_SPACING_MARK) {
i += Character.charCount(c);
if (i >= patternLength)
break;
c = normalizedPattern.codePointAt(i);
sequenceBuffer.appendCodePoint(c);
}
String ea = produceEquivalentAlternation(sequenceBuffer.toString());
newPattern.setLength(newPattern.length() - Character.charCount(lastCodePoint));
newPattern.append("(?:").append(ea).append(")");
} else if (c == '[' && lastCodePoint != '\\') {
i = normalizeCharClass(newPattern, i);
} else {
newPattern.appendCodePoint(c);
}
lastCodePoint = c;
i += Character.charCount(c);
}
normalizedPattern = newPattern.toString();
}
/**
* Complete the character class being parsed and add a set of alternations
* to it that will match the canonical equivalences of the characters within
* the class.
*/
private int normalizeCharClass(StringBuilder newPattern, int i) {
StringBuilder charClass = new StringBuilder();
StringBuilder eq = null;
int lastCodePoint = -1;
String result;
i++;
charClass.append("[");
while (true) {
int c = normalizedPattern.codePointAt(i);
StringBuilder sequenceBuffer;
if (c == ']' && lastCodePoint != '\\') {
charClass.append((char) c);
break;
} else if (Character.getType(c) == Character.NON_SPACING_MARK) {
sequenceBuffer = new StringBuilder();
sequenceBuffer.appendCodePoint(lastCodePoint);
while (Character.getType(c) == Character.NON_SPACING_MARK) {
sequenceBuffer.appendCodePoint(c);
i += Character.charCount(c);
if (i >= normalizedPattern.length())
break;
c = normalizedPattern.codePointAt(i);
}
String ea = produceEquivalentAlternation(sequenceBuffer.toString());
charClass.setLength(charClass.length() - Character.charCount(lastCodePoint));
if (eq == null)
eq = new StringBuilder();
eq.append('|');
eq.append(ea);
} else {
charClass.appendCodePoint(c);
i++;
}
if (i == normalizedPattern.length())
throw error("Unclosed character class");
lastCodePoint = c;
}
if (eq != null) {
result = "(?:" + charClass.toString() + eq.toString() + ")";
} else {
result = charClass.toString();
}
newPattern.append(result);
return i;
}
/**
* Given a specific sequence composed of a regular character and combining
* marks that follow it, produce the alternation that will match all
* canonical equivalences of that sequence.
*/
private String produceEquivalentAlternation(String source) {
int len = countChars(source, 0, 1);
if (source.length() == len)
// source has one character.
return source;
String base = source.substring(0, len);
String combiningMarks = source.substring(len);
String[] perms = producePermutations(combiningMarks);
StringBuilder result = new StringBuilder(source);
// Add combined permutations
for (int x = 0; x < perms.length; x++) {
String next = base + perms[x];
if (x > 0)
result.append("|" + next);
next = composeOneStep(next);
if (next != null)
result.append("|" + produceEquivalentAlternation(next));
}
return result.toString();
}
/**
* Returns an array of strings that have all the possible permutations of
* the characters in the input string. This is used to get a list of all
* possible orderings of a set of combining marks. Note that some of the
* permutations are invalid because of combining class collisions, and these
* possibilities must be removed because they are not canonically
* equivalent.
*/
private String[] producePermutations(String input) {
if (input.length() == countChars(input, 0, 1))
return new String[] { input };
if (input.length() == countChars(input, 0, 2)) {
int c0 = Character.codePointAt(input, 0);
int c1 = Character.codePointAt(input, Character.charCount(c0));
if (getClass(c1) == getClass(c0)) {
return new String[] { input };
}
String[] result = new String[2];
result[0] = input;
StringBuilder sb = new StringBuilder(2);
sb.appendCodePoint(c1);
sb.appendCodePoint(c0);
result[1] = sb.toString();
return result;
}
int length = 1;
int nCodePoints = countCodePoints(input);
for (int x = 1; x < nCodePoints; x++)
length = length * (x + 1);
String[] temp = new String[length];
int combClass[] = new int[nCodePoints];
for (int x = 0, i = 0; x < nCodePoints; x++) {
int c = Character.codePointAt(input, i);
combClass[x] = getClass(c);
i += Character.charCount(c);
}
// For each char, take it out and add the permutations
// of the remaining chars
int index = 0;
int len;
// offset maintains the index in code units.
loop: for (int x = 0, offset = 0; x < nCodePoints; x++, offset += len) {
len = countChars(input, offset, 1);
boolean skip = false;
for (int y = x - 1; y >= 0; y--) {
if (combClass[y] == combClass[x]) {
continue loop;
}
}
StringBuilder sb = new StringBuilder(input);
String otherChars = sb.delete(offset, offset + len).toString();
String[] subResult = producePermutations(otherChars);
String prefix = input.substring(offset, offset + len);
for (int y = 0; y < subResult.length; y++)
temp[index++] = prefix + subResult[y];
}
String[] result = new String[index];
for (int x = 0; x < index; x++)
result[x] = temp[x];
return result;
}
private int getClass(int c) {
return sun.text.Normalizer.getCombiningClass(c);
}
/**
* Attempts to compose input by combining the first character with the first
* combining mark following it. Returns a String that is the composition of
* the leading character with its first combining mark followed by the
* remaining combining marks. Returns null if the first two characters
* cannot be further composed.
*/
private String composeOneStep(String input) {
int len = countChars(input, 0, 2);
String firstTwoCharacters = input.substring(0, len);
String result = Normalizer.normalize(firstTwoCharacters, Normalizer.Form.NFC);
if (result.equals(firstTwoCharacters))
return null;
else {
String remainder = input.substring(len);
return result + remainder;
}
}
/**
* Preprocess any \Q...\E sequences in `temp', meta-quoting them. See the
* description of `quotemeta' in perlfunc(1).
*/
private void RemoveQEQuoting() {
final int pLen = patternLength;
int i = 0;
while (i < pLen - 1) {
if (temp[i] != '\\')
i += 1;
else if (temp[i + 1] != 'Q')
i += 2;
else
break;
}
if (i >= pLen - 1) // No \Q sequence found
return;
int j = i;
i += 2;
int[] newtemp = new int[j + 3 * (pLen - i) + 2];
System.arraycopy(temp, 0, newtemp, 0, j);
boolean inQuote = true;
boolean beginQuote = true;
while (i < pLen) {
int c = temp[i++];
if (!ASCII.isAscii(c) || ASCII.isAlpha(c)) {
newtemp[j++] = c;
} else if (ASCII.isDigit(c)) {
if (beginQuote) {
/*
* A unicode escape \[0xu] could be before this quote, and
* we don't want this numeric char to processed as part of
* the escape.
*/
newtemp[j++] = '\\';
newtemp[j++] = 'x';
newtemp[j++] = '3';
}
newtemp[j++] = c;
} else if (c != '\\') {
if (inQuote)
newtemp[j++] = '\\';
newtemp[j++] = c;
} else if (inQuote) {
if (temp[i] == 'E') {
i++;
inQuote = false;
} else {
newtemp[j++] = '\\';
newtemp[j++] = '\\';
}
} else {
if (temp[i] == 'Q') {
i++;
inQuote = true;
beginQuote = true;
continue;
} else {
newtemp[j++] = c;
if (i != pLen)
newtemp[j++] = temp[i++];
}
}
beginQuote = false;
}
patternLength = j;
temp = Arrays.copyOf(newtemp, j + 2); // double zero termination
}
/**
* Copies regular expression to an int array and invokes the parsing of the
* expression which will create the object tree.
*/
private void compile() {
// Handle canonical equivalences
if (has(CANON_EQ) && !has(LITERAL)) {
normalize();
} else {
normalizedPattern = pattern;
}
patternLength = normalizedPattern.length();
// Copy pattern to int array for convenience
// Use double zero to terminate pattern
temp = new int[patternLength + 2];
hasSupplementary = false;
int c, count = 0;
// Convert all chars into code points
for (int x = 0; x < patternLength; x += Character.charCount(c)) {
c = normalizedPattern.codePointAt(x);
if (isSupplementary(c)) {
hasSupplementary = true;
}
temp[count++] = c;
}
patternLength = count; // patternLength now in code points
if (!has(LITERAL))
RemoveQEQuoting();
// Allocate all temporary objects here.
buffer = new int[32];
groupHeadAndTailNodes = new ArrayList(10);
groupHeadAndTailNodes.add(null);
namedGroups = null;
if (has(LITERAL)) {
// Literal pattern handling
matchRoot = newSlice(temp, patternLength, hasSupplementary);
matchRoot.setNext(lastAccept);
} else {
// Start recursive descent parsing
matchRoot = expr(lastAccept);
// Check extra pattern characters
if (patternLength != cursor) {
if (peek() == ')') {
throw error("Unmatched closing ')'");
} else {
throw error("Unexpected internal error");
}
}
}
// Peephole optimization
if (matchRoot instanceof Slice) {
root = BnM.optimize(matchRoot);
if (root == matchRoot) {
root = hasSupplementary ? new StartS(matchRoot) : new Start(matchRoot);
}
} else if (matchRoot instanceof Begin || matchRoot instanceof First) {
root = matchRoot;
} else {
root = hasSupplementary ? new StartS(matchRoot) : new Start(matchRoot);
}
// Release temporary storage
temp = null;
buffer = null;
patternLength = 0;
compiled = true;
}
Map namedGroups() {
if (namedGroups == null)
namedGroups = new HashMap(2);
return namedGroups;
}
/**
* Used to print out a subtree of the Pattern to help with debugging.
*/
private static void printObjectTree(Node node) {
while (node != null) {
/*
* if (node instanceof Prolog) { System.out.println(node);
* printObjectTree(((Prolog) node).loop); System.out.println(
* "**** end contents prolog loop"); } else if (node instanceof
* Loop) { System.out.println(node); printObjectTree(((Loop)
* node).body); System.out.println("**** end contents Loop body");
*/
if (node instanceof Curly) {
System.out.println(node);
printObjectTree(((Curly) node).beginNode);
System.out.println("**** end contents Curly body");
/*
* } else if (node instanceof GroupCurly) {
* System.out.println(node); printObjectTree(((GroupCurly)
* node).atom); System.out.println(
* "**** end contents GroupCurly body");
*/
} else if (node instanceof GroupTail) {
System.out.println(node);
System.out.println("Tail next is " + node.getNext());
return;
} else {
System.out.println(node);
}
node = node.getNext();
if (node != null)
System.out.println("->next:");
if (node == Pattern.accept) {
System.out.println("Accept Node");
node = null;
}
}
}
/**
* Used to accumulate information about a subtree of the object graph so
* that optimizations can be applied to the subtree.
*/
static final class TreeInfo {
int minLength;
int maxLength;
boolean maxValid;
boolean deterministic;
TreeInfo() {
reset();
}
void reset() {
minLength = 0;
maxLength = 0;
maxValid = true;
deterministic = true;
}
}
/*
* The following private methods are mainly used to improve the readability
* of the code. In order to let the Java compiler easily inline them, we
* should not put many assertions or error checks in them.
*/
/**
* Indicates whether a particular flag is set or not.
*/
private boolean has(int f) {
return (flags & f) != 0;
}
/**
* Match next character, signal error if failed.
*/
private void accept(int ch, String s) {
int testChar = temp[cursor++];
if (has(COMMENTS))
testChar = parsePastWhitespace(testChar);
if (ch != testChar) {
throw error(s);
}
}
/**
* Mark the end of pattern with a specific character.
*/
private void mark(int c) {
temp[patternLength] = c;
}
/**
* Peek the next character, and do not advance the cursor.
*/
private int peek() {
int ch = temp[cursor];
if (has(COMMENTS))
ch = peekPastWhitespace(ch);
return ch;
}
/**
* Read the next character, and advance the cursor by one.
*/
private int read() {
int ch = temp[cursor++];
if (has(COMMENTS))
ch = parsePastWhitespace(ch);
return ch;
}
/**
* Read the next character, and advance the cursor by one, ignoring the
* COMMENTS setting
*/
private int readEscaped() {
int ch = temp[cursor++];
return ch;
}
/**
* Advance the cursor by one, and peek the next character.
*/
private int next() {
int ch = temp[++cursor];
if (has(COMMENTS))
ch = peekPastWhitespace(ch);
return ch;
}
/**
* Advance the cursor by one, and peek the next character, ignoring the
* COMMENTS setting
*/
private int nextEscaped() {
int ch = temp[++cursor];
return ch;
}
/**
* If in xmode peek past whitespace and comments.
*/
private int peekPastWhitespace(int ch) {
while (ASCII.isSpace(ch) || ch == '#') {
while (ASCII.isSpace(ch))
ch = temp[++cursor];
if (ch == '#') {
ch = peekPastLine();
}
}
return ch;
}
/**
* If in xmode parse past whitespace and comments.
*/
private int parsePastWhitespace(int ch) {
while (ASCII.isSpace(ch) || ch == '#') {
while (ASCII.isSpace(ch))
ch = temp[cursor++];
if (ch == '#')
ch = parsePastLine();
}
return ch;
}
/**
* xmode parse past comment to end of line.
*/
private int parsePastLine() {
int ch = temp[cursor++];
while (ch != 0 && !isLineSeparator(ch))
ch = temp[cursor++];
return ch;
}
/**
* xmode peek past comment to end of line.
*/
private int peekPastLine() {
int ch = temp[++cursor];
while (ch != 0 && !isLineSeparator(ch))
ch = temp[++cursor];
return ch;
}
/**
* Determines if character is a line separator in the current mode
*/
private boolean isLineSeparator(int ch) {
if (has(UNIX_LINES)) {
return ch == '\n';
} else {
return (ch == '\n' || ch == '\r' || (ch | 1) == '\u2029' || ch == '\u0085');
}
}
/**
* Read the character after the next one, and advance the cursor by two.
*/
private int skip() {
int i = cursor;
int ch = temp[i + 1];
cursor = i + 2;
return ch;
}
/**
* Unread one next character, and retreat cursor by one.
*/
private void unread() {
cursor--;
}
/**
* Internal method used for handling all syntax errors. The pattern is
* displayed with a pointer to aid in locating the syntax error.
*/
private PatternSyntaxException error(String s) {
return new PatternSyntaxException(s, normalizedPattern, cursor - 1);
}
/**
* Determines if there is any supplementary character or unpaired surrogate
* in the specified range.
*/
private boolean findSupplementary(int start, int end) {
for (int i = start; i < end; i++) {
if (isSupplementary(temp[i]))
return true;
}
return false;
}
/**
* Determines if the specified code point is a supplementary character or
* unpaired surrogate.
*/
private static final boolean isSupplementary(int ch) {
return ch >= Character.MIN_SUPPLEMENTARY_CODE_POINT || Character.isSurrogate((char) ch);
}
/**
* The following methods handle the main parsing. They are sorted according
* to their precedence order, the lowest one first.
*/
/**
* The expression is parsed with branch nodes added for alternations. This
* may be called recursively to parse sub expressions that may contain
* alternations.
*/
private Node expr(Node end) {
Node prev = null;
Node firstTail = null;
Branch branch = null;
Node branchConn = null;
for (;;) {
Node node = sequence(end);
Node nodeTail = root; // double return
if (prev == null) {
prev = node;
firstTail = nodeTail;
} else {
// Branch
if (branchConn == null) {
branchConn = new BranchConn();
branchConn.setNext(end);
}
if (node == end) {
// if the node returned from sequence() is "end"
// we have an empty expr, set a null atom into
// the branch to indicate to go "next" directly.
node = null;
} else {
// the "tail.next" of each atom goes to branchConn
nodeTail.setNext(branchConn);
}
if (prev == branch) {
branch.add(node);
} else {
if (prev == end) {
prev = null;
} else {
// replace the "end" with "branchConn" at its tail.next
// when put the "prev" into the branch as the first
// atom.
firstTail.setNext(branchConn);
}
prev = branch = new Branch(prev, node, branchConn);
}
}
if (peek() != '|') {
return prev;
}
next();
}
}
@SuppressWarnings("fallthrough")
/**
* Parsing of sequences between alternations.
*/
private Node sequence(Node end) {
Node head = null;
Node tail = null;
Node node = null;
LOOP: for (;;) {
int ch = peek();
switch (ch) {
case '(':
// Because group handles its own closure,
// we need to treat it differently
node = group0();
// Check for comment or flag group
if (node == null)
continue;
if (head == null)
head = node;
else
tail.setNext(node);
// Double return: Tail was returned in root
tail = root;
continue;
case '[':
node = clazz(true);
break;
case '\\':
ch = nextEscaped();
if (ch == 'p' || ch == 'P') {
boolean oneLetter = true;
boolean comp = (ch == 'P');
ch = next(); // Consume { if present
if (ch != '{') {
unread();
} else {
oneLetter = false;
}
node = family(oneLetter, comp);
} else {
unread();
node = atom();
}
break;
case '^':
next();
if (has(MULTILINE)) {
if (has(UNIX_LINES))
node = new UnixCaret();
else
node = new Caret();
} else {
node = new Begin();
}
break;
case '$':
next();
if (has(UNIX_LINES))
node = new UnixDollar(has(MULTILINE));
else
node = new Dollar(has(MULTILINE));
break;
case '.':
next();
if (has(DOTALL)) {
node = new All();
} else {
if (has(UNIX_LINES))
node = new UnixDot();
else {
node = new Dot();
}
}
break;
case '|':
case ')':
break LOOP;
case ']': // Now interpreting dangling ] and } as literals
case '}':
node = atom();
break;
case '?':
case '*':
case '+':
next();
throw error("Dangling meta character '" + ((char) ch) + "'");
case 0:
if (cursor >= patternLength) {
break LOOP;
}
// Fall through
default:
node = atom();
break;
}
node = closure(node, node);
if (head == null) {
head = tail = node;
} else {
tail.setNext(node);
tail = node;
}
}
if (head == null) {
return end;
}
tail.setNext(end);
root = tail; // double return
return head;
}
@SuppressWarnings("fallthrough")
/**
* Parse and add a new Single or Slice.
*/
private Node atom() {
int first = 0;
int prev = -1;
boolean hasSupplementary = false;
int ch = peek();
for (;;) {
switch (ch) {
case '*':
case '+':
case '?':
case '{':
if (first > 1) {
cursor = prev; // Unwind one character
first--;
}
break;
case '$':
case '.':
case '^':
case '(':
case '[':
case '|':
case ')':
break;
case '\\':
ch = nextEscaped();
if (ch == 'p' || ch == 'P') { // Property
if (first > 0) { // Slice is waiting; handle it first
unread();
break;
} else { // No slice; just return the family node
boolean comp = (ch == 'P');
boolean oneLetter = true;
ch = next(); // Consume { if present
if (ch != '{')
unread();
else
oneLetter = false;
return family(oneLetter, comp);
}
}
unread();
prev = cursor;
ch = escape(false, first == 0, false);
if (ch >= 0) {
append(ch, first);
first++;
if (isSupplementary(ch)) {
hasSupplementary = true;
}
ch = peek();
continue;
} else if (first == 0) {
return root;
}
// Unwind meta escape sequence
cursor = prev;
break;
case 0:
if (cursor >= patternLength) {
break;
}
// Fall through
default:
prev = cursor;
append(ch, first);
first++;
if (isSupplementary(ch)) {
hasSupplementary = true;
}
ch = next();
continue;
}
break;
}
if (first == 1) {
return newSingle(buffer[0]);
} else {
return newSlice(buffer, first, hasSupplementary);
}
}
private void append(int ch, int len) {
if (len >= buffer.length) {
int[] tmp = new int[len + len];
System.arraycopy(buffer, 0, tmp, 0, len);
buffer = tmp;
}
buffer[len] = ch;
}
/**
* Parses a backref greedily, taking as many numbers as it can. The first
* digit is always treated as a backref, but multi digit numbers are only
* treated as a backref if at least that many backrefs exist at this point
* in the regex.
*/
private Node ref(int refNum) {
boolean done = false;
while (!done) {
int ch = peek();
switch (ch) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
int newRefNum = (refNum * 10) + (ch - '0');
// Add another number if it doesn't make a group
// that doesn't exist
if (capturingGroupCount - 1 < newRefNum) {
done = true;
break;
}
refNum = newRefNum;
read();
break;
default:
done = true;
break;
}
}
if (has(CASE_INSENSITIVE))
return new CIBackRef(refNum, has(UNICODE_CASE));
else
return new BackRef(refNum);
}
/**
* Parses an escape sequence to determine the actual value that needs to be
* matched. If -1 is returned and create was true a new object was added to
* the tree to handle the escape sequence. If the returned value is greater
* than zero, it is the value that matches the escape sequence.
*/
private int escape(boolean inclass, boolean create, boolean isrange) {
int ch = skip();
switch (ch) {
case '0':
return o();
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if (inclass)
break;
if (create) {
root = ref((ch - '0'));
}
return -1;
case 'A':
if (inclass)
break;
if (create)
root = new Begin();
return -1;
case 'B':
if (inclass)
break;
if (create)
root = new Bound(Bound.NONE, has(UNICODE_CHARACTER_CLASS));
return -1;
case 'C':
break;
case 'D':
if (create)
root = has(UNICODE_CHARACTER_CLASS) ? new Utype(UnicodeProp.DIGIT).complement()
: new Ctype(ASCII.DIGIT).complement();
return -1;
case 'E':
case 'F':
break;
case 'G':
if (inclass)
break;
if (create)
root = new LastMatch();
return -1;
case 'H':
if (create)
root = new HorizWS().complement();
return -1;
case 'I':
case 'J':
case 'K':
case 'L':
case 'M':
case 'N':
case 'O':
case 'P':
case 'Q':
break;
case 'R':
if (inclass)
break;
if (create)
root = new LineEnding();
return -1;
case 'S':
if (create)
root = has(UNICODE_CHARACTER_CLASS) ? new Utype(UnicodeProp.WHITE_SPACE).complement()
: new Ctype(ASCII.SPACE).complement();
return -1;
case 'T':
case 'U':
break;
case 'V':
if (create)
root = new VertWS().complement();
return -1;
case 'W':
if (create)
root = has(UNICODE_CHARACTER_CLASS) ? new Utype(UnicodeProp.WORD).complement()
: new Ctype(ASCII.WORD).complement();
return -1;
case 'X':
case 'Y':
break;
case 'Z':
if (inclass)
break;
if (create) {
if (has(UNIX_LINES))
root = new UnixDollar(false);
else
root = new Dollar(false);
}
return -1;
case 'a':
return '\007';
case 'b':
if (inclass)
break;
if (create)
root = new Bound(Bound.BOTH, has(UNICODE_CHARACTER_CLASS));
return -1;
case 'c':
return c();
case 'd':
if (create)
root = has(UNICODE_CHARACTER_CLASS) ? new Utype(UnicodeProp.DIGIT) : new Ctype(ASCII.DIGIT);
return -1;
case 'e':
return '\033';
case 'f':
return '\f';
case 'g':
break;
case 'h':
if (create)
root = new HorizWS();
return -1;
case 'i':
case 'j':
break;
case 'k':
if (inclass)
break;
if (read() != '<')
throw error("\\k is not followed by '<' for named capturing group");
String name = groupname(read());
if (!namedGroups().containsKey(name))
throw error("(named capturing group <" + name + "> does not exit");
if (create) {
if (has(CASE_INSENSITIVE))
root = new CIBackRef(namedGroups().get(name), has(UNICODE_CASE));
else
root = new BackRef(namedGroups().get(name));
}
return -1;
case 'l':
case 'm':
break;
case 'n':
return '\n';
case 'o':
case 'p':
case 'q':
break;
case 'r':
return '\r';
case 's':
if (create)
root = has(UNICODE_CHARACTER_CLASS) ? new Utype(UnicodeProp.WHITE_SPACE) : new Ctype(ASCII.SPACE);
return -1;
case 't':
return '\t';
case 'u':
return u();
case 'v':
// '\v' was implemented as VT/0x0B in releases < 1.8 (though
// undocumented). In JDK8 '\v' is specified as a predefined
// character class for all vertical whitespace characters.
// So [-1, root=VertWS node] pair is returned (instead of a
// single 0x0B). This breaks the range if '\v' is used as
// the start or end value, such as [\v-...] or [...-\v], in
// which a single definite value (0x0B) is expected. For
// compatibility concern '\013'/0x0B is returned if isrange.
if (isrange)
return '\013';
if (create)
root = new VertWS();
return -1;
case 'w':
if (create)
root = has(UNICODE_CHARACTER_CLASS) ? new Utype(UnicodeProp.WORD) : new Ctype(ASCII.WORD);
return -1;
case 'x':
return x();
case 'y':
break;
case 'z':
if (inclass)
break;
if (create)
root = new End();
return -1;
default:
return ch;
}
throw error("Illegal/unsupported escape sequence");
}
/**
* Parse a character class, and return the node that matches it.
*
* Consumes a ] on the way out if consume is true. Usually consume is true
* except for the case of [abc&&def] where def is a separate right hand node
* with "understood" brackets.
*/
private CharProperty clazz(boolean consume) {
CharProperty prev = null;
CharProperty node = null;
BitClass bits = new BitClass();
boolean include = true;
boolean firstInClass = true;
int ch = next();
for (;;) {
switch (ch) {
case '^':
// Negates if first char in a class, otherwise literal
if (firstInClass) {
if (temp[cursor - 1] != '[')
break;
ch = next();
include = !include;
continue;
} else {
// ^ not first in class, treat as literal
break;
}
case '[':
firstInClass = false;
node = clazz(true);
if (prev == null)
prev = node;
else
prev = union(prev, node);
ch = peek();
continue;
case '&':
firstInClass = false;
ch = next();
if (ch == '&') {
ch = next();
CharProperty rightNode = null;
while (ch != ']' && ch != '&') {
if (ch == '[') {
if (rightNode == null)
rightNode = clazz(true);
else
rightNode = union(rightNode, clazz(true));
} else { // abc&&def
unread();
rightNode = clazz(false);
}
ch = peek();
}
if (rightNode != null)
node = rightNode;
if (prev == null) {
if (rightNode == null)
throw error("Bad class syntax");
else
prev = rightNode;
} else {
prev = intersection(prev, node);
}
} else {
// treat as a literal &
unread();
break;
}
continue;
case 0:
firstInClass = false;
if (cursor >= patternLength)
throw error("Unclosed character class");
break;
case ']':
firstInClass = false;
if (prev != null) {
if (consume)
next();
return prev;
}
break;
default:
firstInClass = false;
break;
}
node = range(bits);
if (include) {
if (prev == null) {
prev = node;
} else {
if (prev != node)
prev = union(prev, node);
}
} else {
if (prev == null) {
prev = node.complement();
} else {
if (prev != node)
prev = setDifference(prev, node);
}
}
ch = peek();
}
}
private CharProperty bitsOrSingle(BitClass bits, int ch) {
/*
* Bits can only handle codepoints in [u+0000-u+00ff] range. Use
* "single" node instead of bits when dealing with unicode case folding
* for codepoints listed below. (1)Uppercase out of range: u+00ff,
* u+00b5 toUpperCase(u+00ff) -> u+0178 toUpperCase(u+00b5) -> u+039c
* (2)LatinSmallLetterLongS u+17f toUpperCase(u+017f) -> u+0053
* (3)LatinSmallLetterDotlessI u+131 toUpperCase(u+0131) -> u+0049
* (4)LatinCapitalLetterIWithDotAbove u+0130 toLowerCase(u+0130) ->
* u+0069 (5)KelvinSign u+212a toLowerCase(u+212a) ==> u+006B
* (6)AngstromSign u+212b toLowerCase(u+212b) ==> u+00e5
*/
int d;
if (ch < 256 && !(has(CASE_INSENSITIVE) && has(UNICODE_CASE)
&& (ch == 0xff || ch == 0xb5 || ch == 0x49 || ch == 0x69 || // I
// and
// i
ch == 0x53 || ch == 0x73 || // S and s
ch == 0x4b || ch == 0x6b || // K and k
ch == 0xc5 || ch == 0xe5))) // A+ring
return bits.add(ch, flags());
return newSingle(ch);
}
/**
* Parse a single character or a character range in a character class and
* return its representative node.
*/
private CharProperty range(BitClass bits) {
int ch = peek();
if (ch == '\\') {
ch = nextEscaped();
if (ch == 'p' || ch == 'P') { // A property
boolean comp = (ch == 'P');
boolean oneLetter = true;
// Consume { if present
ch = next();
if (ch != '{')
unread();
else
oneLetter = false;
return family(oneLetter, comp);
} else { // ordinary escape
boolean isrange = temp[cursor + 1] == '-';
unread();
ch = escape(true, true, isrange);
if (ch == -1)
return (CharProperty) root;
}
} else {
next();
}
if (ch >= 0) {
if (peek() == '-') {
int endRange = temp[cursor + 1];
if (endRange == '[') {
return bitsOrSingle(bits, ch);
}
if (endRange != ']') {
next();
int m = peek();
if (m == '\\') {
m = escape(true, false, true);
} else {
next();
}
if (m < ch) {
throw error("Illegal character range");
}
if (has(CASE_INSENSITIVE))
return caseInsensitiveRangeFor(ch, m);
else
return rangeFor(ch, m);
}
}
return bitsOrSingle(bits, ch);
}
throw error("Unexpected character '" + ((char) ch) + "'");
}
/**
* Parses a Unicode character family and returns its representative node.
*/
private CharProperty family(boolean singleLetter, boolean maybeComplement) {
next();
String name;
CharProperty node = null;
if (singleLetter) {
int c = temp[cursor];
if (!Character.isSupplementaryCodePoint(c)) {
name = String.valueOf((char) c);
} else {
name = new String(temp, cursor, 1);
}
read();
} else {
int i = cursor;
mark('}');
while (read() != '}') {
}
mark('\000');
int j = cursor;
if (j > patternLength)
throw error("Unclosed character family");
if (i + 1 >= j)
throw error("Empty character family");
name = new String(temp, i, j - i - 1);
}
int i = name.indexOf('=');
if (i != -1) {
// property construct \p{name=value}
String value = name.substring(i + 1);
name = name.substring(0, i).toLowerCase(Locale.ENGLISH);
if ("sc".equals(name) || "script".equals(name)) {
node = unicodeScriptPropertyFor(value);
} else if ("blk".equals(name) || "block".equals(name)) {
node = unicodeBlockPropertyFor(value);
} else if ("gc".equals(name) || "general_category".equals(name)) {
node = charPropertyNodeFor(value);
} else {
throw error("Unknown Unicode property {name=<" + name + ">, " + "value=<" + value + ">}");
}
} else {
if (name.startsWith("In")) {
// \p{inBlockName}
node = unicodeBlockPropertyFor(name.substring(2));
} else if (name.startsWith("Is")) {
// \p{isGeneralCategory} and \p{isScriptName}
name = name.substring(2);
UnicodeProp uprop = UnicodeProp.forName(name);
if (uprop != null)
node = new Utype(uprop);
if (node == null)
node = CharPropertyNames.charPropertyFor(name);
if (node == null)
node = unicodeScriptPropertyFor(name);
} else {
if (has(UNICODE_CHARACTER_CLASS)) {
UnicodeProp uprop = UnicodeProp.forPOSIXName(name);
if (uprop != null)
node = new Utype(uprop);
}
if (node == null)
node = charPropertyNodeFor(name);
}
}
if (maybeComplement) {
if (node instanceof Category || node instanceof Block)
hasSupplementary = true;
node = node.complement();
}
return node;
}
/**
* Returns a CharProperty matching all characters belong to a UnicodeScript.
*/
private CharProperty unicodeScriptPropertyFor(String name) {
final Character.UnicodeScript script;
try {
script = Character.UnicodeScript.forName(name);
} catch (IllegalArgumentException iae) {
throw error("Unknown character script name {" + name + "}");
}
return new Script(script);
}
/**
* Returns a CharProperty matching all characters in a UnicodeBlock.
*/
private CharProperty unicodeBlockPropertyFor(String name) {
final Character.UnicodeBlock block;
try {
block = Character.UnicodeBlock.forName(name);
} catch (IllegalArgumentException iae) {
throw error("Unknown character block name {" + name + "}");
}
return new Block(block);
}
/**
* Returns a CharProperty matching all characters in a named property.
*/
private CharProperty charPropertyNodeFor(String name) {
CharProperty p = CharPropertyNames.charPropertyFor(name);
if (p == null)
throw error("Unknown character property name {" + name + "}");
return p;
}
/**
* Parses and returns the name of a "named capturing group", the trailing
* ">" is consumed after parsing.
*/
private String groupname(int ch) {
StringBuilder sb = new StringBuilder();
sb.append(Character.toChars(ch));
while (ASCII.isLower(ch = read()) || ASCII.isUpper(ch) || ASCII.isDigit(ch)) {
sb.append(Character.toChars(ch));
}
if (sb.length() == 0)
throw error("named capturing group has 0 length name");
if (ch != '>')
throw error("named capturing group is missing trailing '>'");
return sb.toString();
}
/**
* Parses a group and returns the head node of a set of nodes that process
* the group. Sometimes a double return system is used where the tail is
* returned in root.
*/
private Node group0() {
boolean capturingGroup = false;
Node head = null;
Node tail = null;
int save = flags;
root = null;
int ch = next();
if (ch == '?') {
ch = skip();
switch (ch) {
case ':': // (?:xxx) pure group
head = createGroup(true);
tail = root;
head.setNext(expr(tail));
break;
case '=': // (?=xxx) and (?!xxx) lookahead
case '!':
head = createGroup(true);
tail = root;
head.setNext(expr(tail));
if (ch == '=') {
head = tail = new Pos(head);
} else {
head = tail = new Neg(head);
}
break;
case '>': // (?>xxx) independent group
head = tail = new AtomicGroup(expr(accept));
break;
case '<': // (? is already defined");
capturingGroup = true;
head = createGroup(false);
tail = root;
namedGroups().put(name, capturingGroupCount - 1);
head.setNext(expr(tail));
break;
} else if (ch == '-') {
ch = peek();
int groupNumber;
if ((groupNumber = doesGroupNumberFollowBefore('>')) == -1
&& (groupNumber = doesGroupNameFollowBefore('>')) == -1) {
throw error("Illegal pop group capture syntax");
}
tail = new PopCapture(groupNumber);
head = expr(tail);
break;
}
int start = cursor;
head = createGroup(true);
tail = root;
head.setNext(expr(tail));
tail.setNext(lookbehindEnd);
TreeInfo info = new TreeInfo();
head.study(info);
if (info.maxValid == false) {
throw error("Look-behind group does not have " + "an obvious maximum length");
}
boolean hasSupplementary = findSupplementary(start, patternLength);
if (ch == '=') {
head = tail = (hasSupplementary ? new BehindS(head, info.maxLength, info.minLength)
: new Behind(head, info.maxLength, info.minLength));
} else if (ch == '!') {
head = tail = (hasSupplementary ? new NotBehindS(head, info.maxLength, info.minLength)
: new NotBehind(head, info.maxLength, info.minLength));
} else {
throw error("Unknown look-behind group");
}
break;
case '(': // (?(groupNumber)yes|no)
int group;
Conditional conditional;
if ((group = doesGroupNumberFollowBefore(')')) != -1
|| (group = doesGroupNameFollowBefore(')')) != -1) {
conditional = new ConditionalGP(group);
} else {
Pos pos = new Pos(expr(accept));
accept(')', "Unclosed condition");
conditional = new ConditionalLookahead(pos);
}
head = createGroup(true);// Conditionals are really uncaptured
// groups
tail = root;
head.next = expr(tail);
if (head.next instanceof Branch) {
Branch branch = (Branch) head.next;
conditional.yes = branch.atoms[0];
conditional.not = branch.atoms[1];
head.next = conditional;
} else {
conditional.yes = head.next;
head.next = conditional;
head.next.next = tail;
}
break;
case '$':
case '@':
throw error("Unknown group type");
default: // (?xxx:) inlined match flags or (?digit) recursive group
// call
unread();
int groupNumber;
if ((groupNumber = doesGroupNumberFollowBefore(')')) != -1
|| (groupNumber = doesGroupNameFollowBefore(')')) != -1) {
unread();
head = tail = new RecursiveGroupCall(groupNumber);
} else {
addFlag();
ch = read();
if (ch == ')') {
return null; // Inline modifier only
}
if (ch != ':') {
throw error("Unknown inline modifier");
}
head = createGroup(true);
tail = root;
head.setNext(expr(tail));
break;
}
}
} else { // (xxx) a regular group
capturingGroup = true;
head = createGroup(false);
tail = root;
head.setNext(expr(tail));
}
accept(')', "Unclosed group");
flags = save;
// Check for quantifiers
Node node = closure(head, tail);
if (node == head) { // No closure
root = tail;
return node; // Dual return
}
if (head == tail) { // Zero length assertion
root = node;
return node; // Dual return
}
root = node;
return node;
}
private int doesGroupNameFollowBefore(int closing) {
int ch = peek();
int save = cursor;
if (ASCII.isLower(ch) || ASCII.isUpper(ch)) {
StringBuilder sb = new StringBuilder();
while (ASCII.isLower(ch = read()) || ASCII.isUpper(ch) || ASCII.isDigit(ch)) {
sb.append(Character.toChars(ch));
}
if (!namedGroups().containsKey(sb.toString()) || ch != closing) {
cursor = save;
return -1;
}
return namedGroups.get(sb.toString());
}
return -1;
}
private int doesGroupNumberFollowBefore(int closing) {
int number = 0;
int ch;
int save = cursor;
while (ASCII.isDigit(ch = read())) {
number = number * 10 + ch - '0';
}
if (number <= 0 || number >= capturingGroupCount || ch != closing) {
cursor = save;
return -1;
}
return number;
}
/**
* Create group head and tail nodes using double return. If the group is
* created with anonymous true then it is a pure group and should not affect
* group counting.
*/
private Node createGroup(boolean anonymous) {
int localIndex = localCount++;
int groupIndex = 0;
if (!anonymous)
groupIndex = capturingGroupCount++;
GroupHead head = new GroupHead(localIndex);
GroupTail tail = new GroupTail(localIndex, groupIndex);
root = tail;
if (!anonymous) {
groupHeadAndTailNodes.add(new GroupHeadAndTail(head, tail));
}
return head;
}
@SuppressWarnings("fallthrough")
/**
* Parses inlined match flags and set them appropriately.
*/
private void addFlag() {
int ch = peek();
for (;;) {
switch (ch) {
case 'i':
flags |= CASE_INSENSITIVE;
break;
case 'm':
flags |= MULTILINE;
break;
case 's':
flags |= DOTALL;
break;
case 'd':
flags |= UNIX_LINES;
break;
case 'u':
flags |= UNICODE_CASE;
break;
case 'c':
flags |= CANON_EQ;
break;
case 'x':
flags |= COMMENTS;
break;
case 'U':
flags |= (UNICODE_CHARACTER_CLASS | UNICODE_CASE);
break;
case '-': // subFlag then fall through
ch = next();
subFlag();
default:
return;
}
ch = next();
}
}
@SuppressWarnings("fallthrough")
/**
* Parses the second part of inlined match flags and turns off flags
* appropriately.
*/
private void subFlag() {
int ch = peek();
for (;;) {
switch (ch) {
case 'i':
flags &= ~CASE_INSENSITIVE;
break;
case 'm':
flags &= ~MULTILINE;
break;
case 's':
flags &= ~DOTALL;
break;
case 'd':
flags &= ~UNIX_LINES;
break;
case 'u':
flags &= ~UNICODE_CASE;
break;
case 'c':
flags &= ~CANON_EQ;
break;
case 'x':
flags &= ~COMMENTS;
break;
case 'U':
flags &= ~(UNICODE_CHARACTER_CLASS | UNICODE_CASE);
default:
return;
}
ch = next();
}
}
static final int MAX_REPS = 0x7FFFFFFF;
static final int GREEDY = 0;
static final int LAZY = 1;
/**
* Processes repetition. If the next character peeked is a quantifier then
* new nodes must be appended to handle the repetition. Prev could be a
* single or a group, so it could be a chain of nodes.
*/
private Node closure(Node beginNode, Node endNode) {
Node atom;
int ch = peek();
switch (ch) {
case '?':
ch = next();
if (ch == '?') {
next();
return new Curly(beginNode, endNode, 0, 1, LAZY);
} else if (ch == '+') {
next();
return new AtomicGroup(new Curly(beginNode, endNode, 0, 1, GREEDY));
}
return new Curly(beginNode, endNode, 0, 1, GREEDY);
case '*':
ch = next();
if (ch == '?') {
next();
return new Curly(beginNode, endNode, 0, MAX_REPS, LAZY);
} else if (ch == '+') {
next();
return new AtomicGroup(new Curly(beginNode, endNode, 0, MAX_REPS, GREEDY));
}
return new Curly(beginNode, endNode, 0, MAX_REPS, GREEDY);
case '+':
ch = next();
if (ch == '?') {
next();
return new Curly(beginNode, endNode, 1, MAX_REPS, LAZY);
} else if (ch == '+') {
next();
return new AtomicGroup(new Curly(beginNode, endNode, 1, MAX_REPS, GREEDY));
}
return new Curly(beginNode, endNode, 1, MAX_REPS, GREEDY);
case '{':
ch = temp[cursor + 1];
if (ASCII.isDigit(ch)) {
skip();
int cmin = 0;
do {
cmin = cmin * 10 + (ch - '0');
} while (ASCII.isDigit(ch = read()));
int cmax = cmin;
if (ch == ',') {
ch = read();
cmax = MAX_REPS;
if (ch != '}') {
cmax = 0;
while (ASCII.isDigit(ch)) {
cmax = cmax * 10 + (ch - '0');
ch = read();
}
}
}
if (ch != '}')
throw error("Unclosed counted closure");
if (((cmin) | (cmax) | (cmax - cmin)) < 0)
throw error("Illegal repetition range");
Node curly;
ch = peek();
if (ch == '?') {
next();
curly = new Curly(beginNode, endNode, cmin, cmax, LAZY);
} else if (ch == '+') {
next();
curly = new AtomicGroup(new Curly(beginNode, endNode, cmin, cmax, GREEDY));
} else {
curly = new Curly(beginNode, endNode, cmin, cmax, GREEDY);
}
return curly;
} else {
throw error("Illegal repetition");
}
default:
return beginNode;
}
}
/**
* Utility method for parsing control escape sequences.
*/
private int c() {
if (cursor < patternLength) {
return read() ^ 64;
}
throw error("Illegal control escape sequence");
}
/**
* Utility method for parsing octal escape sequences.
*/
private int o() {
int n = read();
if (((n - '0') | ('7' - n)) >= 0) {
int m = read();
if (((m - '0') | ('7' - m)) >= 0) {
int o = read();
if ((((o - '0') | ('7' - o)) >= 0) && (((n - '0') | ('3' - n)) >= 0)) {
return (n - '0') * 64 + (m - '0') * 8 + (o - '0');
}
unread();
return (n - '0') * 8 + (m - '0');
}
unread();
return (n - '0');
}
throw error("Illegal octal escape sequence");
}
/**
* Utility method for parsing hexadecimal escape sequences.
*/
private int x() {
int n = read();
if (ASCII.isHexDigit(n)) {
int m = read();
if (ASCII.isHexDigit(m)) {
return ASCII.toDigit(n) * 16 + ASCII.toDigit(m);
}
} else if (n == '{' && ASCII.isHexDigit(peek())) {
int ch = 0;
while (ASCII.isHexDigit(n = read())) {
ch = (ch << 4) + ASCII.toDigit(n);
if (ch > Character.MAX_CODE_POINT)
throw error("Hexadecimal codepoint is too big");
}
if (n != '}')
throw error("Unclosed hexadecimal escape sequence");
return ch;
}
throw error("Illegal hexadecimal escape sequence");
}
/**
* Utility method for parsing unicode escape sequences.
*/
private int cursor() {
return cursor;
}
private void setcursor(int pos) {
cursor = pos;
}
private int uxxxx() {
int n = 0;
for (int i = 0; i < 4; i++) {
int ch = read();
if (!ASCII.isHexDigit(ch)) {
throw error("Illegal Unicode escape sequence");
}
n = n * 16 + ASCII.toDigit(ch);
}
return n;
}
private int u() {
int n = uxxxx();
if (Character.isHighSurrogate((char) n)) {
int cur = cursor();
if (read() == '\\' && read() == 'u') {
int n2 = uxxxx();
if (Character.isLowSurrogate((char) n2))
return Character.toCodePoint((char) n, (char) n2);
}
setcursor(cur);
}
return n;
}
//
// Utility methods for code point support
//
private static final int countChars(CharSequence seq, int index, int lengthInCodePoints) {
// optimization
if (lengthInCodePoints == 1 && !Character.isHighSurrogate(seq.charAt(index))) {
assert (index >= 0 && index < seq.length());
return 1;
}
int length = seq.length();
int x = index;
if (lengthInCodePoints >= 0) {
assert (index >= 0 && index < length);
for (int i = 0; x < length && i < lengthInCodePoints; i++) {
if (Character.isHighSurrogate(seq.charAt(x++))) {
if (x < length && Character.isLowSurrogate(seq.charAt(x))) {
x++;
}
}
}
return x - index;
}
assert (index >= 0 && index <= length);
if (index == 0) {
return 0;
}
int len = -lengthInCodePoints;
for (int i = 0; x > 0 && i < len; i++) {
if (Character.isLowSurrogate(seq.charAt(--x))) {
if (x > 0 && Character.isHighSurrogate(seq.charAt(x - 1))) {
x--;
}
}
}
return index - x;
}
private static final int countCodePoints(CharSequence seq) {
int length = seq.length();
int n = 0;
for (int i = 0; i < length;) {
n++;
if (Character.isHighSurrogate(seq.charAt(i++))) {
if (i < length && Character.isLowSurrogate(seq.charAt(i))) {
i++;
}
}
}
return n;
}
/**
* Creates a bit vector for matching Latin-1 values. A normal BitClass never
* matches values above Latin-1, and a complemented BitClass always matches
* values above Latin-1.
*/
private static final class BitClass extends BmpCharProperty {
final boolean[] bits;
BitClass() {
bits = new boolean[256];
}
private BitClass(boolean[] bits) {
this.bits = bits;
}
BitClass add(int c, int flags) {
assert c >= 0 && c <= 255;
if ((flags & CASE_INSENSITIVE) != 0) {
if (ASCII.isAscii(c)) {
bits[ASCII.toUpper(c)] = true;
bits[ASCII.toLower(c)] = true;
} else if ((flags & UNICODE_CASE) != 0) {
bits[Character.toLowerCase(c)] = true;
bits[Character.toUpperCase(c)] = true;
}
}
bits[c] = true;
return this;
}
boolean isSatisfiedBy(int ch) {
return ch < 256 && bits[ch];
}
}
/**
* Returns a suitably optimized, single character matcher.
*/
private CharProperty newSingle(final int ch) {
if (has(CASE_INSENSITIVE)) {
int lower, upper;
if (has(UNICODE_CASE)) {
upper = Character.toUpperCase(ch);
lower = Character.toLowerCase(upper);
if (upper != lower)
return new SingleU(lower);
} else if (ASCII.isAscii(ch)) {
lower = ASCII.toLower(ch);
upper = ASCII.toUpper(ch);
if (lower != upper)
return new SingleI(lower, upper);
}
}
if (isSupplementary(ch))
return new SingleS(ch); // Match a given Unicode character
return new Single(ch); // Match a given BMP character
}
/**
* Utility method for creating a string slice matcher.
*/
private Node newSlice(int[] buf, int count, boolean hasSupplementary) {
int[] tmp = new int[count];
if (has(CASE_INSENSITIVE)) {
if (has(UNICODE_CASE)) {
for (int i = 0; i < count; i++) {
tmp[i] = Character.toLowerCase(Character.toUpperCase(buf[i]));
}
return hasSupplementary ? new SliceUS(tmp) : new SliceU(tmp);
}
for (int i = 0; i < count; i++) {
tmp[i] = ASCII.toLower(buf[i]);
}
return hasSupplementary ? new SliceIS(tmp) : new SliceI(tmp);
}
for (int i = 0; i < count; i++) {
tmp[i] = buf[i];
}
return hasSupplementary ? new SliceS(tmp) : new Slice(tmp);
}
/**
* The following classes are the building components of the object tree that
* represents a compiled regular expression. The object tree is made of
* individual elements that handle constructs in the Pattern. Each type of
* object knows how to match its equivalent construct with the match()
* method.
*/
/**
* Base class for all node classes. Subclasses should override the match()
* method as appropriate. This class is an accepting node, so its match()
* always returns true.
*/
static class Node {
private Node next;
Node getNext() {
return next;
}
void setNext(Node next) {
this.next = next;
}
Node() {
this.setNext(Pattern.accept);
}
/**
* This method implements the classic accept node.
*/
boolean match(Matcher matcher, int i, CharSequence seq) {
matcher.last = i;
matcher.setGroup0(seq, matcher.first, matcher.last);
return true;
}
/**
* This method is good for all zero length assertions.
*/
boolean study(TreeInfo info) {
if (getNext() != null) {
return getNext().study(info);
} else {
return info.deterministic;
}
}
}
static class LastNode extends Node {
/**
* This method implements the classic accept node with the addition of a
* check to see if the match occurred using all of the input.
*/
boolean match(Matcher matcher, int i, CharSequence seq) {
if (matcher.acceptMode == Matcher.ENDANCHOR && i != matcher.to)
return false;
matcher.last = i;
matcher.setGroup0(seq, matcher.first, matcher.last);
return true;
}
}
/**
* Used for REs that can start anywhere within the input string. This
* basically tries to match repeatedly at each spot in the input string,
* moving forward after each try. An anchored search or a BnM will bypass
* this node completely.
*/
static class Start extends Node {
int minLength;
Start(Node node) {
this.setNext(node);
TreeInfo info = new TreeInfo();
getNext().study(info);
minLength = info.minLength;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
if (i > matcher.to - minLength) {
matcher.hitEnd = true;
return false;
}
int guard = matcher.to - minLength;
for (; i <= guard; i++) {
if (getNext().match(matcher, i, seq)) {
matcher.first = i;
matcher.setGroup0(seq, matcher.first, matcher.last);
return true;
}
}
matcher.hitEnd = true;
return false;
}
boolean study(TreeInfo info) {
getNext().study(info);
info.maxValid = false;
info.deterministic = false;
return false;
}
}
/*
* StartS supports supplementary characters, including unpaired surrogates.
*/
static final class StartS extends Start {
StartS(Node node) {
super(node);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
if (i > matcher.to - minLength) {
matcher.hitEnd = true;
return false;
}
int guard = matcher.to - minLength;
while (i <= guard) {
// if ((ret = getNext().match(matcher, i, seq)) || i == guard)
if (getNext().match(matcher, i, seq)) {
matcher.first = i;
matcher.setGroup0(seq, matcher.first, matcher.last);
return true;
}
if (i == guard)
break;
// Optimization to move to the next character. This is
// faster than countChars(seq, i, 1).
if (Character.isHighSurrogate(seq.charAt(i++))) {
if (i < seq.length() && Character.isLowSurrogate(seq.charAt(i))) {
i++;
}
}
}
matcher.hitEnd = true;
return false;
}
}
/**
* Node to anchor at the beginning of input. This object implements the
* match for a \A sequence, and the caret anchor will use this if not in
* multiline mode.
*/
static final class Begin extends Node {
boolean match(Matcher matcher, int i, CharSequence seq) {
int fromIndex = (matcher.anchoringBounds) ? matcher.from : 0;
if (i == fromIndex && getNext().match(matcher, i, seq)) {
matcher.first = i;
matcher.setGroup0(seq, i, matcher.last);
return true;
} else {
return false;
}
}
}
/**
* Node to anchor at the end of input. This is the absolute end, so this
* should not match at the last newline before the end as $ will.
*/
static final class End extends Node {
boolean match(Matcher matcher, int i, CharSequence seq) {
int endIndex = (matcher.anchoringBounds) ? matcher.to : matcher.getTextLength();
if (i == endIndex) {
matcher.hitEnd = true;
return getNext().match(matcher, i, seq);
}
return false;
}
}
/**
* Node to anchor at the beginning of a line. This is essentially the object
* to match for the multiline ^.
*/
static final class Caret extends Node {
boolean match(Matcher matcher, int i, CharSequence seq) {
int startIndex = matcher.from;
int endIndex = matcher.to;
if (!matcher.anchoringBounds) {
startIndex = 0;
endIndex = matcher.getTextLength();
}
// Perl does not match ^ at end of input even after newline
if (i == endIndex) {
matcher.hitEnd = true;
return false;
}
if (i > startIndex) {
char ch = seq.charAt(i - 1);
if (ch != '\n' && ch != '\r' && (ch | 1) != '\u2029' && ch != '\u0085') {
return false;
}
// Should treat /r/n as one newline
if (ch == '\r' && seq.charAt(i) == '\n')
return false;
}
return getNext().match(matcher, i, seq);
}
}
/**
* Node to anchor at the beginning of a line when in unixdot mode.
*/
static final class UnixCaret extends Node {
boolean match(Matcher matcher, int i, CharSequence seq) {
int startIndex = matcher.from;
int endIndex = matcher.to;
if (!matcher.anchoringBounds) {
startIndex = 0;
endIndex = matcher.getTextLength();
}
// Perl does not match ^ at end of input even after newline
if (i == endIndex) {
matcher.hitEnd = true;
return false;
}
if (i > startIndex) {
char ch = seq.charAt(i - 1);
if (ch != '\n') {
return false;
}
}
return getNext().match(matcher, i, seq);
}
}
/**
* Node to match the location where the last match ended. This is used for
* the \G construct.
*/
static final class LastMatch extends Node {
boolean match(Matcher matcher, int i, CharSequence seq) {
if (i != matcher.oldLast)
return false;
return getNext().match(matcher, i, seq);
}
}
/**
* Node to anchor at the end of a line or the end of input based on the
* multiline mode.
*
* When not in multiline mode, the $ can only match at the very end of the
* input, unless the input ends in a line terminator in which it matches
* right before the last line terminator.
*
* Note that \r\n is considered an atomic line terminator.
*
* Like ^ the $ operator matches at a position, it does not match the line
* terminators themselves.
*/
static final class Dollar extends Node {
boolean multiline;
Dollar(boolean mul) {
multiline = mul;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int endIndex = (matcher.anchoringBounds) ? matcher.to : matcher.getTextLength();
if (!multiline) {
if (i < endIndex - 2)
return false;
if (i == endIndex - 2) {
char ch = seq.charAt(i);
if (ch != '\r')
return false;
ch = seq.charAt(i + 1);
if (ch != '\n')
return false;
}
}
// Matches before any line terminator; also matches at the
// end of input
// Before line terminator:
// If multiline, we match here no matter what
// If not multiline, fall through so that the end
// is marked as hit; this must be a /r/n or a /n
// at the very end so the end was hit; more input
// could make this not match here
if (i < endIndex) {
char ch = seq.charAt(i);
if (ch == '\n') {
// No match between \r\n
if (i > 0 && seq.charAt(i - 1) == '\r')
return false;
if (multiline)
return getNext().match(matcher, i, seq);
} else if (ch == '\r' || ch == '\u0085' || (ch | 1) == '\u2029') {
if (multiline)
return getNext().match(matcher, i, seq);
} else { // No line terminator, no match
return false;
}
}
// Matched at current end so hit end
matcher.hitEnd = true;
// If a $ matches because of end of input, then more input
// could cause it to fail!
matcher.requireEnd = true;
return getNext().match(matcher, i, seq);
}
boolean study(TreeInfo info) {
getNext().study(info);
return info.deterministic;
}
}
/**
* Node to anchor at the end of a line or the end of input based on the
* multiline mode when in unix lines mode.
*/
static final class UnixDollar extends Node {
boolean multiline;
UnixDollar(boolean mul) {
multiline = mul;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int endIndex = (matcher.anchoringBounds) ? matcher.to : matcher.getTextLength();
if (i < endIndex) {
char ch = seq.charAt(i);
if (ch == '\n') {
// If not multiline, then only possible to
// match at very end or one before end
if (multiline == false && i != endIndex - 1)
return false;
// If multiline return getNext().match without setting
// matcher.hitEnd
if (multiline)
return getNext().match(matcher, i, seq);
} else {
return false;
}
}
// Matching because at the end or 1 before the end;
// more input could change this so set hitEnd
matcher.hitEnd = true;
// If a $ matches because of end of input, then more input
// could cause it to fail!
matcher.requireEnd = true;
return getNext().match(matcher, i, seq);
}
boolean study(TreeInfo info) {
getNext().study(info);
return info.deterministic;
}
}
/**
* Node class that matches a Unicode line ending '\R'
*/
static final class LineEnding extends Node {
boolean match(Matcher matcher, int i, CharSequence seq) {
// (u+000Du+000A|[u+000Au+000Bu+000Cu+000Du+0085u+2028u+2029])
if (i < matcher.to) {
int ch = seq.charAt(i);
if (ch == 0x0A || ch == 0x0B || ch == 0x0C || ch == 0x85 || ch == 0x2028 || ch == 0x2029)
return getNext().match(matcher, i + 1, seq);
if (ch == 0x0D) {
i++;
if (i < matcher.to && seq.charAt(i) == 0x0A)
i++;
return getNext().match(matcher, i, seq);
}
} else {
matcher.hitEnd = true;
}
return false;
}
boolean study(TreeInfo info) {
info.minLength++;
info.maxLength += 2;
return getNext().study(info);
}
}
/**
* Abstract node class to match one character satisfying some boolean
* property.
*/
private static abstract class CharProperty extends Node {
abstract boolean isSatisfiedBy(int ch);
CharProperty complement() {
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
return !CharProperty.this.isSatisfiedBy(ch);
}
};
}
boolean match(Matcher matcher, int i, CharSequence seq) {
if (i < matcher.to) {
int ch = Character.codePointAt(seq, i);
return isSatisfiedBy(ch) && getNext().match(matcher, i + Character.charCount(ch), seq);
} else {
matcher.hitEnd = true;
return false;
}
}
boolean study(TreeInfo info) {
info.minLength++;
info.maxLength++;
return getNext().study(info);
}
}
/**
* Optimized version of CharProperty that works only for properties never
* satisfied by Supplementary characters.
*/
private static abstract class BmpCharProperty extends CharProperty {
boolean match(Matcher matcher, int i, CharSequence seq) {
if (i < matcher.to) {
return isSatisfiedBy(seq.charAt(i)) && getNext().match(matcher, i + 1, seq);
} else {
matcher.hitEnd = true;
return false;
}
}
}
/**
* Node class that matches a Supplementary Unicode character
*/
static final class SingleS extends CharProperty {
final int c;
SingleS(int c) {
this.c = c;
}
boolean isSatisfiedBy(int ch) {
return ch == c;
}
}
/**
* Optimization -- matches a given BMP character
*/
static final class Single extends BmpCharProperty {
final int c;
Single(int c) {
this.c = c;
}
boolean isSatisfiedBy(int ch) {
return ch == c;
}
}
/**
* Case insensitive matches a given BMP character
*/
static final class SingleI extends BmpCharProperty {
final int lower;
final int upper;
SingleI(int lower, int upper) {
this.lower = lower;
this.upper = upper;
}
boolean isSatisfiedBy(int ch) {
return ch == lower || ch == upper;
}
}
/**
* Unicode case insensitive matches a given Unicode character
*/
static final class SingleU extends CharProperty {
final int lower;
SingleU(int lower) {
this.lower = lower;
}
boolean isSatisfiedBy(int ch) {
return lower == ch || lower == Character.toLowerCase(Character.toUpperCase(ch));
}
}
/**
* Node class that matches a Unicode block.
*/
static final class Block extends CharProperty {
final Character.UnicodeBlock block;
Block(Character.UnicodeBlock block) {
this.block = block;
}
boolean isSatisfiedBy(int ch) {
return block == Character.UnicodeBlock.of(ch);
}
}
/**
* Node class that matches a Unicode script
*/
static final class Script extends CharProperty {
final Character.UnicodeScript script;
Script(Character.UnicodeScript script) {
this.script = script;
}
boolean isSatisfiedBy(int ch) {
return script == Character.UnicodeScript.of(ch);
}
}
/**
* Node class that matches a Unicode category.
*/
static final class Category extends CharProperty {
final int typeMask;
Category(int typeMask) {
this.typeMask = typeMask;
}
boolean isSatisfiedBy(int ch) {
return (typeMask & (1 << Character.getType(ch))) != 0;
}
}
/**
* Node class that matches a Unicode "type"
*/
static final class Utype extends CharProperty {
final UnicodeProp uprop;
Utype(UnicodeProp uprop) {
this.uprop = uprop;
}
boolean isSatisfiedBy(int ch) {
return uprop.is(ch);
}
}
/**
* Node class that matches a POSIX type.
*/
static final class Ctype extends BmpCharProperty {
final int ctype;
Ctype(int ctype) {
this.ctype = ctype;
}
boolean isSatisfiedBy(int ch) {
return ch < 128 && ASCII.isType(ch, ctype);
}
}
/**
* Node class that matches a Perl vertical whitespace
*/
static final class VertWS extends BmpCharProperty {
boolean isSatisfiedBy(int cp) {
return (cp >= 0x0A && cp <= 0x0D) || cp == 0x85 || cp == 0x2028 || cp == 0x2029;
}
}
/**
* Node class that matches a Perl horizontal whitespace
*/
static final class HorizWS extends BmpCharProperty {
boolean isSatisfiedBy(int cp) {
return cp == 0x09 || cp == 0x20 || cp == 0xa0 || cp == 0x1680 || cp == 0x180e
|| cp >= 0x2000 && cp <= 0x200a || cp == 0x202f || cp == 0x205f || cp == 0x3000;
}
}
/**
* Base class for all Slice nodes
*/
static class SliceNode extends Node {
int[] buffer;
SliceNode(int[] buf) {
buffer = buf;
}
boolean study(TreeInfo info) {
info.minLength += buffer.length;
info.maxLength += buffer.length;
return getNext().study(info);
}
}
/**
* Node class for a case sensitive/BMP-only sequence of literal characters.
*/
static final class Slice extends SliceNode {
Slice(int[] buf) {
super(buf);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] buf = buffer;
int len = buf.length;
for (int j = 0; j < len; j++) {
if ((i + j) >= matcher.to) {
matcher.hitEnd = true;
return false;
}
if (buf[j] != seq.charAt(i + j))
return false;
}
return getNext().match(matcher, i + len, seq);
}
}
/**
* Node class for a case_insensitive/BMP-only sequence of literal
* characters.
*/
static class SliceI extends SliceNode {
SliceI(int[] buf) {
super(buf);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] buf = buffer;
int len = buf.length;
for (int j = 0; j < len; j++) {
if ((i + j) >= matcher.to) {
matcher.hitEnd = true;
return false;
}
int c = seq.charAt(i + j);
if (buf[j] != c && buf[j] != ASCII.toLower(c))
return false;
}
return getNext().match(matcher, i + len, seq);
}
}
/**
* Node class for a unicode_case_insensitive/BMP-only sequence of literal
* characters. Uses unicode case folding.
*/
static final class SliceU extends SliceNode {
SliceU(int[] buf) {
super(buf);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] buf = buffer;
int len = buf.length;
for (int j = 0; j < len; j++) {
if ((i + j) >= matcher.to) {
matcher.hitEnd = true;
return false;
}
int c = seq.charAt(i + j);
if (buf[j] != c && buf[j] != Character.toLowerCase(Character.toUpperCase(c)))
return false;
}
return getNext().match(matcher, i + len, seq);
}
}
/**
* Node class for a case sensitive sequence of literal characters including
* supplementary characters.
*/
static final class SliceS extends SliceNode {
SliceS(int[] buf) {
super(buf);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] buf = buffer;
int x = i;
for (int j = 0; j < buf.length; j++) {
if (x >= matcher.to) {
matcher.hitEnd = true;
return false;
}
int c = Character.codePointAt(seq, x);
if (buf[j] != c)
return false;
x += Character.charCount(c);
if (x > matcher.to) {
matcher.hitEnd = true;
return false;
}
}
return getNext().match(matcher, x, seq);
}
}
/**
* Node class for a case insensitive sequence of literal characters
* including supplementary characters.
*/
static class SliceIS extends SliceNode {
SliceIS(int[] buf) {
super(buf);
}
int toLower(int c) {
return ASCII.toLower(c);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] buf = buffer;
int x = i;
for (int j = 0; j < buf.length; j++) {
if (x >= matcher.to) {
matcher.hitEnd = true;
return false;
}
int c = Character.codePointAt(seq, x);
if (buf[j] != c && buf[j] != toLower(c))
return false;
x += Character.charCount(c);
if (x > matcher.to) {
matcher.hitEnd = true;
return false;
}
}
return getNext().match(matcher, x, seq);
}
}
/**
* Node class for a case insensitive sequence of literal characters. Uses
* unicode case folding.
*/
static final class SliceUS extends SliceIS {
SliceUS(int[] buf) {
super(buf);
}
int toLower(int c) {
return Character.toLowerCase(Character.toUpperCase(c));
}
}
private static boolean inRange(int lower, int ch, int upper) {
return lower <= ch && ch <= upper;
}
/**
* Returns node for matching characters within an explicit value range.
*/
private static CharProperty rangeFor(final int lower, final int upper) {
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
return inRange(lower, ch, upper);
}
};
}
/**
* Returns node for matching characters within an explicit value range in a
* case insensitive manner.
*/
private CharProperty caseInsensitiveRangeFor(final int lower, final int upper) {
if (has(UNICODE_CASE))
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
if (inRange(lower, ch, upper))
return true;
int up = Character.toUpperCase(ch);
return inRange(lower, up, upper) || inRange(lower, Character.toLowerCase(up), upper);
}
};
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
return inRange(lower, ch, upper) || ASCII.isAscii(ch)
&& (inRange(lower, ASCII.toUpper(ch), upper) || inRange(lower, ASCII.toLower(ch), upper));
}
};
}
/**
* Implements the Unicode category ALL and the dot metacharacter when in
* dotall mode.
*/
static final class All extends CharProperty {
boolean isSatisfiedBy(int ch) {
return true;
}
}
/**
* Node class for the dot metacharacter when dotall is not enabled.
*/
static final class Dot extends CharProperty {
boolean isSatisfiedBy(int ch) {
return (ch != '\n' && ch != '\r' && (ch | 1) != '\u2029' && ch != '\u0085');
}
}
/**
* Node class for the dot metacharacter when dotall is not enabled but
* UNIX_LINES is enabled.
*/
static final class UnixDot extends CharProperty {
boolean isSatisfiedBy(int ch) {
return ch != '\n';
}
}
/**
* The 0 or 1 quantifier. This one class implements all three types.
*/
/*
* static final class Ques extends Node { Node atom; int type;
*
* Ques(Node node, int type) { this.atom = node; this.type = type; }
*
* boolean match(Matcher matcher, int i, CharSequence seq) { switch (type) {
* case GREEDY: return (atom.match(matcher, i, seq) &&
* getNext().match(matcher, matcher.last, seq)) || getNext().match(matcher,
* i, seq); case LAZY: return getNext().match(matcher, i, seq) ||
* (atom.match(matcher, i, seq) && getNext().match(matcher, matcher.last,
* seq)); case POSSESSIVE: if (atom.match(matcher, i, seq)) i =
* matcher.last; return getNext().match(matcher, i, seq); default: return
* atom.match(matcher, i, seq) && getNext().match(matcher, matcher.last,
* seq); } }
*
* boolean study(TreeInfo info) { if (type != INDEPENDENT) { int minL =
* info.minLength; atom.study(info); info.minLength = minL;
* info.deterministic = false; return getNext().study(info); } else {
* atom.study(info); return getNext().study(info); } } }
*/
/**
* Handles the curly-brace style repetition with a specified minimum and
* maximum occurrences. The * quantifier is handled as a special case. This
* class handles the three types.
*/
static final class Curly extends Node {
Node beginNode;
Node endNode;
int type;
int cmin;
int cmax;
Curly(Node beginNode, Node endNode, int cmin, int cmax, int type) {
this.beginNode = beginNode;
this.endNode = endNode;
this.type = type;
this.cmin = cmin;
this.cmax = cmax;
}
private class MaxLazyRepeater extends Node {
private int counter;
private Node initialEndNext = endNode.getNext();
MaxLazyRepeater(int cmax) {
this.counter = cmax;
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
Node oldEndNodeNext = endNode.getNext();
endNode.setNext(initialEndNext);
boolean r = Curly.this.getNext().match(matcher, i, seq);
endNode.setNext(oldEndNodeNext);
if (r)
return true;
if (counter == 0) {
return false;
}
--counter;
oldEndNodeNext = endNode.getNext();
endNode.setNext(this);
r = beginNode.match(matcher, i, seq);
++counter;
endNode.setNext(oldEndNodeNext);
return r;
}
}
private class Repeater extends Node {
private int counter;
private Node initialEndNext = endNode.getNext();
private boolean isMax;
Repeater(Node next, int counter, boolean isMax) {
this.setNext(next);
this.counter = counter;
this.isMax = isMax;
}
@Override
public boolean match(Matcher matcher, int i, CharSequence seq) {
if (counter == 0) {
Node oldEndNext = endNode.getNext();
endNode.setNext(initialEndNext);
boolean r = getNext().match(matcher, i, seq);
endNode.setNext(oldEndNext);
return r;
}
--counter;
Node oldEndNext = endNode.getNext();
endNode.setNext(this);
boolean r = beginNode.match(matcher, i, seq);
++counter;
endNode.setNext(oldEndNext);
if (isMax)
r = r || getNext().match(matcher, i, seq);
return r;
}
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
if (type == GREEDY) {
Repeater mgr = new Repeater(this.getNext(), cmax - cmin, true);
Repeater mr = new Repeater(mgr, cmin, false);
return mr.match(matcher, i, seq);
} else { // type == LAZY
MaxLazyRepeater mlr = new MaxLazyRepeater(cmax - cmin);
Repeater mr = new Repeater(mlr, cmin, false);
return mr.match(matcher, i, seq);
}
}
boolean study(TreeInfo info) {
// Save original info
int minL = info.minLength;
int maxL = info.maxLength;
boolean maxV = info.maxValid;
boolean detm = info.deterministic;
info.reset();
beginNode.study(info);
int temp = info.minLength * cmin + minL;
if (temp < minL) {
temp = 0xFFFFFFF; // arbitrary large number
}
info.minLength = temp;
if (maxV & info.maxValid) {
temp = info.maxLength * cmax + maxL;
info.maxLength = temp;
if (temp < maxL) {
info.maxValid = false;
}
} else {
info.maxValid = false;
}
if (info.deterministic && cmin == cmax)
info.deterministic = detm;
else
info.deterministic = false;
return getNext().study(info);
}
}
/**
* Handles the curly-brace style repetition with a specified minimum and
* maximum occurrences in deterministic cases. This is an iterative
* optimization over the Prolog and Loop system which would handle this in a
* recursive way. The * quantifier is handled as a special case. If capture
* is true then this class saves group settings and ensures that groups are
* unset when backing off of a group match.
*/
/*
* static final class GroupCurly extends Node { Node atom; int type; int
* cmin; int cmax; int localIndex; int groupIndex; boolean capture;
*
* GroupCurly(Node node, int cmin, int cmax, int type, int local, int group,
* boolean capture) { this.atom = node; this.type = type; this.cmin = cmin;
* this.cmax = cmax; this.localIndex = local; this.groupIndex = group;
* this.capture = capture; }
*
* boolean match(Matcher matcher, int i, CharSequence seq) { int[] groups =
* matcher.groups; int[] locals = matcher.locals; int save0 =
* locals[localIndex]; int save1 = 0; int save2 = 0;
*
* if (capture) { save1 = groups[groupIndex]; save2 = groups[groupIndex +
* 1]; }
*
* // Notify GroupTail there is no need to setup group info // because it
* will be set here locals[localIndex] = -1;
*
* boolean ret = true; for (int j = 0; j < cmin; j++) { if
* (atom.match(matcher, i, seq)) { if (capture) { groups[groupIndex] = i;
* groups[groupIndex + 1] = matcher.last; } i = matcher.last; } else { ret =
* false; break; } } if (ret) { if (type == GREEDY) { ret = match0(matcher,
* i, cmin, seq); } else if (type == LAZY) { ret = match1(matcher, i, cmin,
* seq); } else { ret = match2(matcher, i, cmin, seq); } } if (!ret) {
* locals[localIndex] = save0; if (capture) { groups[groupIndex] = save1;
* groups[groupIndex + 1] = save2; } } return ret; }
*
* // Aggressive group match boolean match0(Matcher matcher, int i, int j,
* CharSequence seq) { // don't back off passing the starting "j" int min =
* j; int[] groups = matcher.groups; int save0 = 0; int save1 = 0; if
* (capture) { save0 = groups[groupIndex]; save1 = groups[groupIndex + 1]; }
* for (;;) { if (j >= cmax) break; if (!atom.match(matcher, i, seq)) break;
* int k = matcher.last - i; if (k <= 0) { if (capture) { groups[groupIndex]
* = i; groups[groupIndex + 1] = i + k; } i = i + k; break; } for (;;) { if
* (capture) { groups[groupIndex] = i; groups[groupIndex + 1] = i + k; } i =
* i + k; if (++j >= cmax) break; if (!atom.match(matcher, i, seq)) break;
* if (i + k != matcher.last) { if (match0(matcher, i, j, seq)) return true;
* break; } } while (j > min) { if (getNext().match(matcher, i, seq)) { if
* (capture) { groups[groupIndex + 1] = i; groups[groupIndex] = i - k; }
* return true; } // backing off i = i - k; if (capture) { groups[groupIndex
* + 1] = i; groups[groupIndex] = i - k; } j--;
*
* } break; } if (capture) { groups[groupIndex] = save0; groups[groupIndex +
* 1] = save1; } return getNext().match(matcher, i, seq); }
*
* // Reluctant matching boolean match1(Matcher matcher, int i, int j,
* CharSequence seq) { for (;;) { if (getNext().match(matcher, i, seq))
* return true; if (j >= cmax) return false; if (!atom.match(matcher, i,
* seq)) return false; if (i == matcher.last) return false; if (capture) {
* matcher.groups[groupIndex] = i; matcher.groups[groupIndex + 1] =
* matcher.last; } i = matcher.last; j++; } }
*
* // Possessive matching boolean match2(Matcher matcher, int i, int j,
* CharSequence seq) { for (; j < cmax; j++) { if (!atom.match(matcher, i,
* seq)) { break; } if (capture) { matcher.groups[groupIndex] = i;
* matcher.groups[groupIndex + 1] = matcher.last; } if (i == matcher.last) {
* break; } i = matcher.last; } return getNext().match(matcher, i, seq); }
*
* boolean study(TreeInfo info) { // Save original info int minL =
* info.minLength; int maxL = info.maxLength; boolean maxV = info.maxValid;
* boolean detm = info.deterministic; info.reset();
*
* atom.study(info);
*
* int temp = info.minLength * cmin + minL; if (temp < minL) { temp =
* 0xFFFFFFF; // Arbitrary large number } info.minLength = temp;
*
* if (maxV & info.maxValid) { temp = info.maxLength * cmax + maxL;
* info.maxLength = temp; if (temp < maxL) { info.maxValid = false; } } else
* { info.maxValid = false; }
*
* if (info.deterministic && cmin == cmax) { info.deterministic = detm; }
* else { info.deterministic = false; } return getNext().study(info); } }
*/
/**
* A Guard node at the end of each atom node in a Branch. It serves the
* purpose of chaining the "match" operation to "next" but not the "study",
* so we can collect the TreeInfo of each atom node without including the
* TreeInfo of the "next".
*/
static final class BranchConn extends Node {
BranchConn() {
};
boolean match(Matcher matcher, int i, CharSequence seq) {
return getNext().match(matcher, i, seq);
}
boolean study(TreeInfo info) {
return info.deterministic;
}
}
/**
* Handles the branching of alternations. Note this is also used for the ?
* quantifier to branch between the case where it matches once and where it
* does not occur.
*/
static final class Branch extends Node {
Node[] atoms = new Node[2];
int size = 2;
Node conn;
Branch(Node first, Node second, Node branchConn) {
conn = branchConn;
atoms[0] = first;
atoms[1] = second;
}
void add(Node node) {
if (size >= atoms.length) {
Node[] tmp = new Node[atoms.length * 2];
System.arraycopy(atoms, 0, tmp, 0, atoms.length);
atoms = tmp;
}
atoms[size++] = node;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
for (int n = 0; n < size; n++) {
if (atoms[n] == null) {
if (conn.getNext().match(matcher, i, seq))
return true;
} else if (atoms[n].match(matcher, i, seq)) {
return true;
}
}
return false;
}
boolean study(TreeInfo info) {
int minL = info.minLength;
int maxL = info.maxLength;
boolean maxV = info.maxValid;
int minL2 = Integer.MAX_VALUE; // arbitrary large enough num
int maxL2 = -1;
for (int n = 0; n < size; n++) {
info.reset();
if (atoms[n] != null)
atoms[n].study(info);
minL2 = Math.min(minL2, info.minLength);
maxL2 = Math.max(maxL2, info.maxLength);
maxV = (maxV & info.maxValid);
}
minL += minL2;
maxL += maxL2;
info.reset();
conn.getNext().study(info);
info.minLength += minL;
info.maxLength += maxL;
info.maxValid &= maxV;
info.deterministic = false;
return false;
}
}
static final class AtomicGroup extends Node {
private Node atom;
AtomicGroup(Node atom) {
this.atom = atom;
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
Vector> captures = matcher.cloneCaptures();
if (atom.match(matcher, i, seq))
i = matcher.last;
else
return false;
boolean r = getNext().match(matcher, i, seq);
if (!r)
matcher.captures = captures;
return r;
}
@Override
boolean study(TreeInfo info) {
atom.study(info);
return getNext().study(info);
}
}
/**
* The GroupHead saves the location where the group begins in the locals and
* restores them when the match is done.
*
* The matchRef is used when a reference to this group is accessed later in
* the expression. The locals will have a negative value in them to indicate
* that we do not want to unset the group if the reference doesn't match.
*/
static final class GroupHead extends Node {
int localIndex;
GroupHead(int localCount) {
localIndex = localCount;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
matcher.localVector.get(localIndex).push(i);
boolean ret = getNext().match(matcher, i, seq);
matcher.localVector.get(localIndex).pop();
return ret;
}
}
/**
* The GroupTail handles the setting of group beginning and ending locations
* when groups are successfully matched. It must also be able to unset
* groups that have to be backed off of.
*
* The GroupTail node is also used when a previous group is referenced, and
* in that case no group information needs to be set.
*/
static final class GroupTail extends Node {
int localIndex;
int groupIndex;
GroupTail(int localCount, int groupCount) {
localIndex = localCount;
// if groupCount <= 0, this is an anonymous group
groupIndex = groupCount;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int tmp = matcher.localVector.get(localIndex).pop();
// Save the group so we can unset it if it
// backs off of a match.
/*
* int groupStart = matcher.groups[groupIndex]; int groupEnd =
* matcher.groups[groupIndex + 1];
*/
if (groupIndex > 0)
matcher.captures.get(groupIndex).push(new Capture(seq, tmp, i));
boolean r = getNext().match(matcher, i, seq);
if (!r && groupIndex > 0)
matcher.captures.get(groupIndex).pop();
matcher.localVector.get(localIndex).push(tmp);
return r;
}
}
static class GroupHeadAndTail {
GroupHead groupHead;
GroupTail groupTail;
GroupHeadAndTail(GroupHead groupHead, GroupTail groupTail) {
this.groupHead = groupHead;
this.groupTail = groupTail;
}
}
static final class PopCapture extends Node {
private int groupIndex;
PopCapture(int groupIndex) {
this.groupIndex = groupIndex;
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
if (matcher.captures.get(groupIndex).isEmpty())
return false;
Capture capture = matcher.captures.get(groupIndex).pop();
boolean r = getNext().match(matcher, i, seq);
if (!r)
matcher.captures.get(groupIndex).push(capture);
return r;
}
}
final class RecursiveGroupCall extends Node {
private GroupHead groupHead;
private GroupTail groupTail;
RecursiveGroupCall(int groupNumber) {
GroupHeadAndTail ghat = groupHeadAndTailNodes.get(groupNumber);
groupHead = ghat.groupHead;
groupTail = ghat.groupTail;
}
private class InternalRecursiveGroupCall extends Node {
boolean first = true;
Node groupTailsNext = groupTail.getNext();
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
if (first) {
first = false;
groupTail.setNext(this);
boolean r = groupHead.match(matcher, i, seq);
groupTail.setNext(groupTailsNext);
return r;
} else {
groupTail.setNext(groupTailsNext);
boolean r = RecursiveGroupCall.this.getNext().match(matcher, i, seq);
groupTail.setNext(this);
return r;
}
}
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
InternalRecursiveGroupCall ircc = new InternalRecursiveGroupCall();
return ircc.match(matcher, i, seq);
}
private boolean recursive = false;
@Override
boolean study(TreeInfo info) {
if (recursive) {
info.maxValid = false;
return false; // We can return something arbitrary here
}
recursive = true;
Node save = groupTail.getNext();
groupTail.setNext(accept);
groupHead.study(info);
recursive = false;
groupTail.setNext(save);
return info.deterministic;
}
}
/**
* This sets up a loop to handle a recursive quantifier structure.
*/
/*
* static final class Prolog extends Node { Loop loop;
*
* Prolog(Loop loop) { this.loop = loop; }
*
* boolean match(Matcher matcher, int i, CharSequence seq) { return
* loop.matchInit(matcher, i, seq); }
*
* boolean study(TreeInfo info) { return loop.study(info); } }
*/
/**
* Handles the repetition count for a greedy Curly. The matchInit is called
* from the Prolog to save the index of where the group beginning is stored.
* A zero length group check occurs in the normal match but is skipped in
* the matchInit.
*/
/*
* static class Loop extends Node { Node body; int countIndex; // local
* count index in matcher locals int beginIndex; // group beginning index
* int cmin, cmax;
*
* Loop(int countIndex, int beginIndex) { this.countIndex = countIndex;
* this.beginIndex = beginIndex; }
*
* boolean match(Matcher matcher, int i, CharSequence seq) { // Avoid
* infinite loop in zero-length case. if (i > matcher.locals[beginIndex]) {
* int count = matcher.locals[countIndex];
*
* // This block is for before we reach the minimum // iterations required
* for the loop to match if (count < cmin) { matcher.locals[countIndex] =
* count + 1; boolean b = body.match(matcher, i, seq); // If match failed we
* must backtrack, so // the loop count should NOT be incremented if (!b)
* matcher.locals[countIndex] = count; // Return success or failure since we
* are under // minimum return b; } // This block is for after we have the
* minimum // iterations required for the loop to match if (count < cmax) {
* matcher.locals[countIndex] = count + 1; boolean b = body.match(matcher,
* i, seq); // If match failed we must backtrack, so // the loop count
* should NOT be incremented if (!b) matcher.locals[countIndex] = count;
* else return true; } } return getNext().match(matcher, i, seq); }
*
* boolean matchInit(Matcher matcher, int i, CharSequence seq) { int save =
* matcher.locals[countIndex]; boolean ret = false; if (0 < cmin) {
* matcher.locals[countIndex] = 1; ret = body.match(matcher, i, seq); } else
* if (0 < cmax) { matcher.locals[countIndex] = 1; ret = body.match(matcher,
* i, seq); if (ret == false) ret = getNext().match(matcher, i, seq); } else
* { ret = getNext().match(matcher, i, seq); } matcher.locals[countIndex] =
* save; return ret; }
*
* boolean study(TreeInfo info) { info.maxValid = false; info.deterministic
* = false; return false; } }
*/
/**
* Handles the repetition count for a reluctant Curly. The matchInit is
* called from the Prolog to save the index of where the group beginning is
* stored. A zero length group check occurs in the normal match but is
* skipped in the matchInit.
*/
/*
* static final class LazyLoop extends Loop { LazyLoop(int countIndex, int
* beginIndex) { super(countIndex, beginIndex); }
*
* boolean match(Matcher matcher, int i, CharSequence seq) { // Check for
* zero length group if (i > matcher.locals[beginIndex]) { int count =
* matcher.locals[countIndex]; if (count < cmin) {
* matcher.locals[countIndex] = count + 1; boolean result =
* body.match(matcher, i, seq); // If match failed we must backtrack, so //
* the loop count should NOT be incremented if (!result)
* matcher.locals[countIndex] = count; return result; } if
* (getNext().match(matcher, i, seq)) return true; if (count < cmax) {
* matcher.locals[countIndex] = count + 1; boolean result =
* body.match(matcher, i, seq); // If match failed we must backtrack, so //
* the loop count should NOT be incremented if (!result)
* matcher.locals[countIndex] = count; return result; } return false; }
* return getNext().match(matcher, i, seq); }
*
* boolean matchInit(Matcher matcher, int i, CharSequence seq) { int save =
* matcher.locals[countIndex]; boolean ret = false; if (0 < cmin) {
* matcher.locals[countIndex] = 1; ret = body.match(matcher, i, seq); } else
* if (getNext().match(matcher, i, seq)) { ret = true; } else if (0 < cmax)
* { matcher.locals[countIndex] = 1; ret = body.match(matcher, i, seq); }
* matcher.locals[countIndex] = save; return ret; }
*
* boolean study(TreeInfo info) { info.maxValid = false; info.deterministic
* = false; return false; } }
*/
/**
* Refers to a group in the regular expression. Attempts to match whatever
* the group referred to last matched.
*/
static class BackRef extends Node {
int groupIndex;
BackRef(int groupCount) {
super();
groupIndex = groupCount;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
// If the referenced group didn't match, neither can this
if (matcher.captures.get(groupIndex).isEmpty())
return false;
Capture last = matcher.captures.get(groupIndex).peek();
int j = last.getStart();
int k = last.getEnd();
int groupSize = k - j;
// If there isn't enough input left no match
if (i + groupSize > matcher.to) {
matcher.hitEnd = true;
return false;
}
// Check each new char to make sure it matches what the group
// referenced matched last time around
for (int index = 0; index < groupSize; index++)
if (seq.charAt(i + index) != seq.charAt(j + index))
return false;
return getNext().match(matcher, i + groupSize, seq);
}
boolean study(TreeInfo info) {
info.maxValid = false;
return getNext().study(info);
}
}
static class CIBackRef extends Node {
int groupIndex;
boolean doUnicodeCase;
CIBackRef(int groupCount, boolean doUnicodeCase) {
super();
groupIndex = groupCount;
this.doUnicodeCase = doUnicodeCase;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
// If the referenced group didn't match, neither can this
if (matcher.captures.get(groupIndex).isEmpty())
return false;
Capture last = matcher.captures.get(groupIndex).peek();
int j = last.getStart();
int k = last.getEnd();
int groupSize = k - j;
// If there isn't enough input left no match
if (i + groupSize > matcher.to) {
matcher.hitEnd = true;
return false;
}
// Check each new char to make sure it matches what the group
// referenced matched last time around
int x = i;
for (int index = 0; index < groupSize; index++) {
int c1 = Character.codePointAt(seq, x);
int c2 = Character.codePointAt(seq, j);
if (c1 != c2) {
if (doUnicodeCase) {
int cc1 = Character.toUpperCase(c1);
int cc2 = Character.toUpperCase(c2);
if (cc1 != cc2 && Character.toLowerCase(cc1) != Character.toLowerCase(cc2))
return false;
} else {
if (ASCII.toLower(c1) != ASCII.toLower(c2))
return false;
}
}
x += Character.charCount(c1);
j += Character.charCount(c2);
}
return getNext().match(matcher, i + groupSize, seq);
}
boolean study(TreeInfo info) {
info.maxValid = false;
return getNext().study(info);
}
}
/**
* Searches until the next instance of its atom. This is useful for finding
* the atom efficiently without passing an instance of it (greedy problem)
* and without a lot of wasted search time (reluctant problem).
*/
static final class First extends Node {
Node atom;
First(Node node) {
this.atom = BnM.optimize(node);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
if (atom instanceof BnM) {
return atom.match(matcher, i, seq) && getNext().match(matcher, matcher.last, seq);
}
for (;;) {
if (i > matcher.to) {
matcher.hitEnd = true;
return false;
}
if (atom.match(matcher, i, seq)) {
return getNext().match(matcher, matcher.last, seq);
}
i += countChars(seq, i, 1);
matcher.first++;
}
}
boolean study(TreeInfo info) {
atom.study(info);
info.maxValid = false;
info.deterministic = false;
return getNext().study(info);
}
}
static class Conditional extends Node {
Node yes;
Node not;
@Override
boolean study(TreeInfo info) {
int minL = info.minLength;
int maxL = info.maxLength;
boolean maxV = info.maxValid;
int minL2 = Integer.MAX_VALUE; // arbitrary large enough num
int maxL2 = -1;
info.reset();
yes.study(info);
minL2 = Math.min(minL2, info.minLength);
maxL2 = Math.max(maxL2, info.maxLength);
maxV = (maxV & info.maxValid);
if (not != null) {
info.reset();
not.study(info);
minL2 = Math.min(minL2, info.minLength);
maxL2 = Math.max(maxL2, info.maxLength);
maxV = (maxV & info.maxValid);
} else {
info.reset();
getNext().study(info);
minL2 = Math.min(minL2, info.minLength);
// Maximum can't get higher as with yes or no
}
info.minLength = minL + minL2;
info.maxLength = maxL + maxL2;
info.maxValid = maxV;
info.deterministic = false;
return false;
}
}
static final class ConditionalGP extends Conditional {
int groupNumber;
ConditionalGP(int groupNumber) {
this.groupNumber = groupNumber;
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
if (!matcher.captures.get(groupNumber).isEmpty()) {
return yes.match(matcher, i, seq);
} else if (not != null) {
return not.match(matcher, i, seq);
} else {
return getNext().match(matcher, i, seq);
}
}
}
static final class ConditionalLookahead extends Conditional {
Pos cond;
ConditionalLookahead(Pos cond) {
this.cond = cond;
}
@Override
boolean match(Matcher matcher, int i, CharSequence seq) {
Vector> captures = matcher.cloneCaptures();
if (cond.match(matcher, i, seq)) {
if (!yes.match(matcher, i, seq)) {
matcher.captures = captures;
return false;
}
return true;
} else if (not != null) {
return not.match(matcher, i, seq);
} else {
return getNext().match(matcher, i, seq);
}
}
}
/**
* Zero width positive lookahead.
*/
static final class Pos extends Node {
Node cond;
Pos(Node cond) {
this.cond = cond;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int savedTo = matcher.to;
boolean conditionMatched = false;
Vector> captures = matcher.cloneCaptures();
// Relax transparent region boundaries for lookahead
if (matcher.transparentBounds)
matcher.to = matcher.getTextLength();
try {
conditionMatched = cond.match(matcher, i, seq);
} finally {
// Reinstate region boundaries
matcher.to = savedTo;
}
if (conditionMatched) {
conditionMatched = conditionMatched & getNext().match(matcher, i, seq);
if (!conditionMatched)
matcher.captures = captures;
}
return conditionMatched;
}
}
/**
* Zero width negative lookahead.
*/
static final class Neg extends Node {
Node cond;
Neg(Node cond) {
this.cond = cond;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int savedTo = matcher.to;
boolean conditionMatched = false;
Vector> captures = matcher.cloneCaptures();
// Relax transparent region boundaries for lookahead
if (matcher.transparentBounds)
matcher.to = matcher.getTextLength();
try {
if (i < matcher.to) {
conditionMatched = !cond.match(matcher, i, seq);
} else {
// If a negative lookahead succeeds then more input
// could cause it to fail!
matcher.requireEnd = true;
conditionMatched = !cond.match(matcher, i, seq);
}
} finally {
// Reinstate region boundaries
matcher.to = savedTo;
}
if (!conditionMatched) {
matcher.captures = captures;
}
return conditionMatched && getNext().match(matcher, i, seq);
}
}
/**
* For use with lookbehinds; matches the position where the lookbehind was
* encountered.
*/
static Node lookbehindEnd = new Node() {
boolean match(Matcher matcher, int i, CharSequence seq) {
return i == matcher.lookbehindTo;
}
};
/**
* Zero width positive lookbehind.
*/
static class Behind extends Node {
Node cond;
int rmax, rmin;
Behind(Node cond, int rmax, int rmin) {
this.cond = cond;
this.rmax = rmax;
this.rmin = rmin;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int savedFrom = matcher.from;
boolean conditionMatched = false;
int startIndex = (!matcher.transparentBounds) ? matcher.from : 0;
int from = Math.max(i - rmax, startIndex);
// Set end boundary
int savedLBT = matcher.lookbehindTo;
matcher.lookbehindTo = i;
// Relax transparent region boundaries for lookbehind
if (matcher.transparentBounds)
matcher.from = 0;
Vector> savedCaptures = matcher.cloneCaptures();
for (int j = i - rmin; !conditionMatched && j >= from; j--) {
conditionMatched = cond.match(matcher, j, seq);
}
matcher.from = savedFrom;
matcher.lookbehindTo = savedLBT;
if (conditionMatched) {
conditionMatched = getNext().match(matcher, i, seq);
if (!conditionMatched) {
matcher.captures = savedCaptures;
}
}
return conditionMatched;
}
}
/**
* Zero width positive lookbehind, including supplementary characters or
* unpaired surrogates.
*/
static final class BehindS extends Behind {
BehindS(Node cond, int rmax, int rmin) {
super(cond, rmax, rmin);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int rmaxChars = countChars(seq, i, -rmax);
int rminChars = countChars(seq, i, -rmin);
int savedFrom = matcher.from;
int startIndex = (!matcher.transparentBounds) ? matcher.from : 0;
boolean conditionMatched = false;
int from = Math.max(i - rmaxChars, startIndex);
// Set end boundary
int savedLBT = matcher.lookbehindTo;
matcher.lookbehindTo = i;
// Relax transparent region boundaries for lookbehind
if (matcher.transparentBounds)
matcher.from = 0;
Vector> savedCaptures = matcher.cloneCaptures();
for (int j = i - rminChars; !conditionMatched && j >= from; j -= j > from ? countChars(seq, j, -1) : 1) {
conditionMatched = cond.match(matcher, j, seq);
}
matcher.from = savedFrom;
matcher.lookbehindTo = savedLBT;
if (conditionMatched) {
conditionMatched = getNext().match(matcher, i, seq);
if (!conditionMatched) {
matcher.captures = savedCaptures;
}
}
return conditionMatched;
}
}
/**
* Zero width negative lookbehind.
*/
static class NotBehind extends Node {
Node cond;
int rmax, rmin;
NotBehind(Node cond, int rmax, int rmin) {
this.cond = cond;
this.rmax = rmax;
this.rmin = rmin;
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int savedLBT = matcher.lookbehindTo;
int savedFrom = matcher.from;
boolean conditionMatched = false;
int startIndex = (!matcher.transparentBounds) ? matcher.from : 0;
int from = Math.max(i - rmax, startIndex);
matcher.lookbehindTo = i;
// Relax transparent region boundaries for lookbehind
if (matcher.transparentBounds)
matcher.from = 0;
Vector> savedCaptures = matcher.cloneCaptures();
for (int j = i - rmin; !conditionMatched && j >= from; j--) {
conditionMatched = cond.match(matcher, j, seq);
}
// Reinstate region boundaries
matcher.from = savedFrom;
matcher.lookbehindTo = savedLBT;
if (conditionMatched) {
matcher.captures = savedCaptures;
}
return !conditionMatched && getNext().match(matcher, i, seq);
}
}
/**
* Zero width negative lookbehind, including supplementary characters or
* unpaired surrogates.
*/
static final class NotBehindS extends NotBehind {
NotBehindS(Node cond, int rmax, int rmin) {
super(cond, rmax, rmin);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int rmaxChars = countChars(seq, i, -rmax);
int rminChars = countChars(seq, i, -rmin);
int savedFrom = matcher.from;
int savedLBT = matcher.lookbehindTo;
boolean conditionMatched = false;
int startIndex = (!matcher.transparentBounds) ? matcher.from : 0;
int from = Math.max(i - rmaxChars, startIndex);
matcher.lookbehindTo = i;
// Relax transparent region boundaries for lookbehind
if (matcher.transparentBounds)
matcher.from = 0;
Vector> savedCaptures = matcher.cloneCaptures();
for (int j = i - rminChars; !conditionMatched && j >= from; j -= j > from ? countChars(seq, j, -1) : 1) {
conditionMatched = cond.match(matcher, j, seq);
}
// Reinstate region boundaries
matcher.from = savedFrom;
matcher.lookbehindTo = savedLBT;
if (conditionMatched) {
matcher.captures = savedCaptures;
}
return !conditionMatched && getNext().match(matcher, i, seq);
}
}
/**
* Returns the set union of two CharProperty nodes.
*/
private static CharProperty union(final CharProperty lhs, final CharProperty rhs) {
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
return lhs.isSatisfiedBy(ch) || rhs.isSatisfiedBy(ch);
}
};
}
/**
* Returns the set intersection of two CharProperty nodes.
*/
private static CharProperty intersection(final CharProperty lhs, final CharProperty rhs) {
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
return lhs.isSatisfiedBy(ch) && rhs.isSatisfiedBy(ch);
}
};
}
/**
* Returns the set difference of two CharProperty nodes.
*/
private static CharProperty setDifference(final CharProperty lhs, final CharProperty rhs) {
return new CharProperty() {
boolean isSatisfiedBy(int ch) {
return !rhs.isSatisfiedBy(ch) && lhs.isSatisfiedBy(ch);
}
};
}
/**
* Handles word boundaries. Includes a field to allow this one class to deal
* with the different types of word boundaries we can match. The word
* characters include underscores, letters, and digits. Non spacing marks
* can are also part of a word if they have a base character, otherwise they
* are ignored for purposes of finding word boundaries.
*/
static final class Bound extends Node {
static int LEFT = 0x1;
static int RIGHT = 0x2;
static int BOTH = 0x3;
static int NONE = 0x4;
int type;
boolean useUWORD;
Bound(int n, boolean useUWORD) {
type = n;
this.useUWORD = useUWORD;
}
boolean isWord(int ch) {
return useUWORD ? UnicodeProp.WORD.is(ch) : (ch == '_' || Character.isLetterOrDigit(ch));
}
int check(Matcher matcher, int i, CharSequence seq) {
int ch;
boolean left = false;
int startIndex = matcher.from;
int endIndex = matcher.to;
if (matcher.transparentBounds) {
startIndex = 0;
endIndex = matcher.getTextLength();
}
if (i > startIndex) {
ch = Character.codePointBefore(seq, i);
left = (isWord(ch) || ((Character.getType(ch) == Character.NON_SPACING_MARK)
&& hasBaseCharacter(matcher, i - 1, seq)));
}
boolean right = false;
if (i < endIndex) {
ch = Character.codePointAt(seq, i);
right = (isWord(ch) || ((Character.getType(ch) == Character.NON_SPACING_MARK)
&& hasBaseCharacter(matcher, i, seq)));
} else {
// Tried to access char past the end
matcher.hitEnd = true;
// The addition of another char could wreck a boundary
matcher.requireEnd = true;
}
return ((left ^ right) ? (right ? LEFT : RIGHT) : NONE);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
return (check(matcher, i, seq) & type) > 0 && getNext().match(matcher, i, seq);
}
}
/**
* Non spacing marks only count as word characters in bounds calculations if
* they have a base character.
*/
private static boolean hasBaseCharacter(Matcher matcher, int i, CharSequence seq) {
int start = (!matcher.transparentBounds) ? matcher.from : 0;
for (int x = i; x >= start; x--) {
int ch = Character.codePointAt(seq, x);
if (Character.isLetterOrDigit(ch))
return true;
if (Character.getType(ch) == Character.NON_SPACING_MARK)
continue;
return false;
}
return false;
}
/**
* Attempts to match a slice in the input using the Boyer-Moore string
* matching algorithm. The algorithm is based on the idea that the pattern
* can be shifted farther ahead in the search text if it is matched right to
* left.
*
* The pattern is compared to the input one character at a time, from the
* rightmost character in the pattern to the left. If the characters all
* match the pattern has been found. If a character does not match, the
* pattern is shifted right a distance that is the maximum of two functions,
* the bad character shift and the good suffix shift. This shift moves the
* attempted match position through the input more quickly than a naive one
* position at a time check.
*
* The bad character shift is based on the character from the text that did
* not match. If the character does not appear in the pattern, the pattern
* can be shifted completely beyond the bad character. If the character does
* occur in the pattern, the pattern can be shifted to line the pattern up
* with the next occurrence of that character.
*
* The good suffix shift is based on the idea that some subset on the right
* side of the pattern has matched. When a bad character is found, the
* pattern can be shifted right by the pattern length if the subset does not
* occur again in pattern, or by the amount of distance to the next
* occurrence of the subset in the pattern.
*
* Boyer-Moore search methods adapted from code by Amy Yu.
*/
static class BnM extends Node {
int[] buffer;
int[] lastOcc;
int[] optoSft;
/**
* Pre calculates arrays needed to generate the bad character shift and
* the good suffix shift. Only the last seven bits are used to see if
* chars match; This keeps the tables small and covers the heavily used
* ASCII range, but occasionally results in an aliased match for the bad
* character shift.
*/
static Node optimize(Node node) {
if (!(node instanceof Slice)) {
return node;
}
int[] src = ((Slice) node).buffer;
int patternLength = src.length;
// The BM algorithm requires a bit of overhead;
// If the pattern is short don't use it, since
// a shift larger than the pattern length cannot
// be used anyway.
if (patternLength < 4) {
return node;
}
int i, j, k;
int[] lastOcc = new int[128];
int[] optoSft = new int[patternLength];
// Precalculate part of the bad character shift
// It is a table for where in the pattern each
// lower 7-bit value occurs
for (i = 0; i < patternLength; i++) {
lastOcc[src[i] & 0x7F] = i + 1;
}
// Precalculate the good suffix shift
// i is the shift amount being considered
NEXT: for (i = patternLength; i > 0; i--) {
// j is the beginning index of suffix being considered
for (j = patternLength - 1; j >= i; j--) {
// Testing for good suffix
if (src[j] == src[j - i]) {
// src[j..len] is a good suffix
optoSft[j - 1] = i;
} else {
// No match. The array has already been
// filled up with correct values before.
continue NEXT;
}
}
// This fills up the remaining of optoSft
// any suffix can not have larger shift amount
// then its sub-suffix. Why???
while (j > 0) {
optoSft[--j] = i;
}
}
// Set the guard value because of unicode compression
optoSft[patternLength - 1] = 1;
if (node instanceof SliceS)
return new BnMS(src, lastOcc, optoSft, node.getNext());
return new BnM(src, lastOcc, optoSft, node.getNext());
}
BnM(int[] src, int[] lastOcc, int[] optoSft, Node next) {
this.buffer = src;
this.lastOcc = lastOcc;
this.optoSft = optoSft;
this.setNext(next);
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] src = buffer;
int patternLength = src.length;
int last = matcher.to - patternLength;
// Loop over all possible match positions in text
NEXT: while (i <= last) {
// Loop over pattern from right to left
for (int j = patternLength - 1; j >= 0; j--) {
int ch = seq.charAt(i + j);
if (ch != src[j]) {
// Shift search to the right by the maximum of the
// bad character shift and the good suffix shift
i += Math.max(j + 1 - lastOcc[ch & 0x7F], optoSft[j]);
continue NEXT;
}
}
// Entire pattern matched starting at i
matcher.first = i;
boolean ret = getNext().match(matcher, i + patternLength, seq);
if (ret) {
matcher.first = i;
matcher.setGroup0(seq, matcher.first, matcher.last);
return true;
}
i++;
}
// BnM is only used as the leading node in the unanchored case,
// and it replaced its Start() which always searches to the end
// if it doesn't find what it's looking for, so hitEnd is true.
matcher.hitEnd = true;
return false;
}
boolean study(TreeInfo info) {
info.minLength += buffer.length;
info.maxValid = false;
return getNext().study(info);
}
}
/**
* Supplementary support version of BnM(). Unpaired surrogates are also
* handled by this class.
*/
static final class BnMS extends BnM {
int lengthInChars;
BnMS(int[] src, int[] lastOcc, int[] optoSft, Node next) {
super(src, lastOcc, optoSft, next);
for (int x = 0; x < buffer.length; x++) {
lengthInChars += Character.charCount(buffer[x]);
}
}
boolean match(Matcher matcher, int i, CharSequence seq) {
int[] src = buffer;
int patternLength = src.length;
int last = matcher.to - lengthInChars;
// Loop over all possible match positions in text
NEXT: while (i <= last) {
// Loop over pattern from right to left
int ch;
for (int j = countChars(seq, i, patternLength), x = patternLength - 1; j > 0; j -= Character
.charCount(ch), x--) {
ch = Character.codePointBefore(seq, i + j);
if (ch != src[x]) {
// Shift search to the right by the maximum of the
// bad character shift and the good suffix shift
int n = Math.max(x + 1 - lastOcc[ch & 0x7F], optoSft[x]);
i += countChars(seq, i, n);
continue NEXT;
}
}
// Entire pattern matched starting at i
matcher.first = i;
boolean ret = getNext().match(matcher, i + lengthInChars, seq);
if (ret) {
matcher.first = i;
matcher.setGroup0(seq, matcher.first, matcher.last);
return true;
}
i += countChars(seq, i, 1);
}
matcher.hitEnd = true;
return false;
}
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
/**
* This must be the very first initializer.
*/
static Node accept = new Node();
static Node lastAccept = new LastNode();
private static class CharPropertyNames {
static CharProperty charPropertyFor(String name) {
CharPropertyFactory m = map.get(name);
return m == null ? null : m.make();
}
private static abstract class CharPropertyFactory {
abstract CharProperty make();
}
private static void defCategory(String name, final int typeMask) {
map.put(name, new CharPropertyFactory() {
CharProperty make() {
return new Category(typeMask);
}
});
}
private static void defRange(String name, final int lower, final int upper) {
map.put(name, new CharPropertyFactory() {
CharProperty make() {
return rangeFor(lower, upper);
}
});
}
private static void defCtype(String name, final int ctype) {
map.put(name, new CharPropertyFactory() {
CharProperty make() {
return new Ctype(ctype);
}
});
}
private static abstract class CloneableProperty extends CharProperty implements Cloneable {
public CloneableProperty clone() {
try {
return (CloneableProperty) super.clone();
} catch (CloneNotSupportedException e) {
throw new AssertionError(e);
}
}
}
private static void defClone(String name, final CloneableProperty p) {
map.put(name, new CharPropertyFactory() {
CharProperty make() {
return p.clone();
}
});
}
private static final HashMap map = new HashMap();
static {
// Unicode character property aliases, defined in
// http://www.unicode.org/Public/UNIDATA/PropertyValueAliases.txt
defCategory("Cn", 1 << Character.UNASSIGNED);
defCategory("Lu", 1 << Character.UPPERCASE_LETTER);
defCategory("Ll", 1 << Character.LOWERCASE_LETTER);
defCategory("Lt", 1 << Character.TITLECASE_LETTER);
defCategory("Lm", 1 << Character.MODIFIER_LETTER);
defCategory("Lo", 1 << Character.OTHER_LETTER);
defCategory("Mn", 1 << Character.NON_SPACING_MARK);
defCategory("Me", 1 << Character.ENCLOSING_MARK);
defCategory("Mc", 1 << Character.COMBINING_SPACING_MARK);
defCategory("Nd", 1 << Character.DECIMAL_DIGIT_NUMBER);
defCategory("Nl", 1 << Character.LETTER_NUMBER);
defCategory("No", 1 << Character.OTHER_NUMBER);
defCategory("Zs", 1 << Character.SPACE_SEPARATOR);
defCategory("Zl", 1 << Character.LINE_SEPARATOR);
defCategory("Zp", 1 << Character.PARAGRAPH_SEPARATOR);
defCategory("Cc", 1 << Character.CONTROL);
defCategory("Cf", 1 << Character.FORMAT);
defCategory("Co", 1 << Character.PRIVATE_USE);
defCategory("Cs", 1 << Character.SURROGATE);
defCategory("Pd", 1 << Character.DASH_PUNCTUATION);
defCategory("Ps", 1 << Character.START_PUNCTUATION);
defCategory("Pe", 1 << Character.END_PUNCTUATION);
defCategory("Pc", 1 << Character.CONNECTOR_PUNCTUATION);
defCategory("Po", 1 << Character.OTHER_PUNCTUATION);
defCategory("Sm", 1 << Character.MATH_SYMBOL);
defCategory("Sc", 1 << Character.CURRENCY_SYMBOL);
defCategory("Sk", 1 << Character.MODIFIER_SYMBOL);
defCategory("So", 1 << Character.OTHER_SYMBOL);
defCategory("Pi", 1 << Character.INITIAL_QUOTE_PUNCTUATION);
defCategory("Pf", 1 << Character.FINAL_QUOTE_PUNCTUATION);
defCategory("L",
((1 << Character.UPPERCASE_LETTER) | (1 << Character.LOWERCASE_LETTER)
| (1 << Character.TITLECASE_LETTER) | (1 << Character.MODIFIER_LETTER)
| (1 << Character.OTHER_LETTER)));
defCategory("M", ((1 << Character.NON_SPACING_MARK) | (1 << Character.ENCLOSING_MARK)
| (1 << Character.COMBINING_SPACING_MARK)));
defCategory("N", ((1 << Character.DECIMAL_DIGIT_NUMBER) | (1 << Character.LETTER_NUMBER)
| (1 << Character.OTHER_NUMBER)));
defCategory("Z", ((1 << Character.SPACE_SEPARATOR) | (1 << Character.LINE_SEPARATOR)
| (1 << Character.PARAGRAPH_SEPARATOR)));
defCategory("C", ((1 << Character.CONTROL) | (1 << Character.FORMAT) | (1 << Character.PRIVATE_USE)
| (1 << Character.SURROGATE))); // Other
defCategory("P",
((1 << Character.DASH_PUNCTUATION) | (1 << Character.START_PUNCTUATION)
| (1 << Character.END_PUNCTUATION) | (1 << Character.CONNECTOR_PUNCTUATION)
| (1 << Character.OTHER_PUNCTUATION) | (1 << Character.INITIAL_QUOTE_PUNCTUATION)
| (1 << Character.FINAL_QUOTE_PUNCTUATION)));
defCategory("S", ((1 << Character.MATH_SYMBOL) | (1 << Character.CURRENCY_SYMBOL)
| (1 << Character.MODIFIER_SYMBOL) | (1 << Character.OTHER_SYMBOL)));
defCategory("LC", ((1 << Character.UPPERCASE_LETTER) | (1 << Character.LOWERCASE_LETTER)
| (1 << Character.TITLECASE_LETTER)));
defCategory("LD",
((1 << Character.UPPERCASE_LETTER) | (1 << Character.LOWERCASE_LETTER)
| (1 << Character.TITLECASE_LETTER) | (1 << Character.MODIFIER_LETTER)
| (1 << Character.OTHER_LETTER) | (1 << Character.DECIMAL_DIGIT_NUMBER)));
defRange("L1", 0x00, 0xFF); // Latin-1
map.put("all", new CharPropertyFactory() {
CharProperty make() {
return new All();
}
});
// Posix regular expression character classes, defined in
// http://www.unix.org/onlinepubs/009695399/basedefs/xbd_chap09.html
defRange("ASCII", 0x00, 0x7F); // ASCII
defCtype("Alnum", ASCII.ALNUM); // Alphanumeric characters
defCtype("Alpha", ASCII.ALPHA); // Alphabetic characters
defCtype("Blank", ASCII.BLANK); // Space and tab characters
defCtype("Cntrl", ASCII.CNTRL); // Control characters
defRange("Digit", '0', '9'); // Numeric characters
defCtype("Graph", ASCII.GRAPH); // printable and visible
defRange("Lower", 'a', 'z'); // Lower-case alphabetic
defRange("Print", 0x20, 0x7E); // Printable characters
defCtype("Punct", ASCII.PUNCT); // Punctuation characters
defCtype("Space", ASCII.SPACE); // Space characters
defRange("Upper", 'A', 'Z'); // Upper-case alphabetic
defCtype("XDigit", ASCII.XDIGIT); // hexadecimal digits
// Java character properties, defined by methods in Character.java
defClone("javaLowerCase", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isLowerCase(ch);
}
});
defClone("javaUpperCase", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isUpperCase(ch);
}
});
defClone("javaAlphabetic", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isAlphabetic(ch);
}
});
defClone("javaIdeographic", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isIdeographic(ch);
}
});
defClone("javaTitleCase", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isTitleCase(ch);
}
});
defClone("javaDigit", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isDigit(ch);
}
});
defClone("javaDefined", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isDefined(ch);
}
});
defClone("javaLetter", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isLetter(ch);
}
});
defClone("javaLetterOrDigit", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isLetterOrDigit(ch);
}
});
defClone("javaJavaIdentifierStart", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isJavaIdentifierStart(ch);
}
});
defClone("javaJavaIdentifierPart", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isJavaIdentifierPart(ch);
}
});
defClone("javaUnicodeIdentifierStart", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isUnicodeIdentifierStart(ch);
}
});
defClone("javaUnicodeIdentifierPart", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isUnicodeIdentifierPart(ch);
}
});
defClone("javaIdentifierIgnorable", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isIdentifierIgnorable(ch);
}
});
defClone("javaSpaceChar", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isSpaceChar(ch);
}
});
defClone("javaWhitespace", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isWhitespace(ch);
}
});
defClone("javaISOControl", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isISOControl(ch);
}
});
defClone("javaMirrored", new CloneableProperty() {
boolean isSatisfiedBy(int ch) {
return Character.isMirrored(ch);
}
});
}
}
/**
* Creates a predicate which can be used to match a string.
*
* @return The predicate which can be used for matching on a string
* @since 1.8
*/
public Predicate asPredicate() {
return s -> matcher(s).find();
}
/**
* Creates a stream from the given input sequence around matches of this
* pattern.
*
*
* The stream returned by this method contains each substring of the input
* sequence that is terminated by another subsequence that matches this
* pattern or is terminated by the end of the input sequence. The substrings
* in the stream are in the order in which they occur in the input. Trailing
* empty strings will be discarded and not encountered in the stream.
*
*
* If this pattern does not match any subsequence of the input then the
* resulting stream has just one element, namely the input sequence in
* string form.
*
*
* When there is a positive-width match at the beginning of the input
* sequence then an empty leading substring is included at the beginning of
* the stream. A zero-width match at the beginning however never produces
* such empty leading substring.
*
*
* If the input sequence is mutable, it must remain constant during the
* execution of the terminal stream operation. Otherwise, the result of the
* terminal stream operation is undefined.
*
* @param input
* The character sequence to be split
*
* @return The stream of strings computed by splitting the input around
* matches of this pattern
* @see #split(CharSequence)
* @since 1.8
*/
public Stream splitAsStream(final CharSequence input) {
class MatcherIterator implements Iterator {
private final Matcher matcher;
// The start position of the next sub-sequence of input
// when current == input.length there are no more elements
private int current;
// null if the next element, if any, needs to obtained
private String nextElement;
// > 0 if there are N next empty elements
private int emptyElementCount;
MatcherIterator() {
this.matcher = matcher(input);
}
public String next() {
if (!hasNext())
throw new NoSuchElementException();
if (emptyElementCount == 0) {
String n = nextElement;
nextElement = null;
return n;
} else {
emptyElementCount--;
return "";
}
}
public boolean hasNext() {
if (nextElement != null || emptyElementCount > 0)
return true;
if (current == input.length())
return false;
// Consume the next matching element
// Count sequence of matching empty elements
while (matcher.find()) {
nextElement = input.subSequence(current, matcher.start()).toString();
current = matcher.end();
if (!nextElement.isEmpty()) {
return true;
} else if (current > 0) { // no empty leading substring for
// zero-width
// match at the beginning of the
// input
emptyElementCount++;
}
}
// Consume last matching element
nextElement = input.subSequence(current, input.length()).toString();
current = input.length();
if (!nextElement.isEmpty()) {
return true;
} else {
// Ignore a terminal sequence of matching empty elements
emptyElementCount = 0;
nextElement = null;
return false;
}
}
}
return StreamSupport.stream(
Spliterators.spliteratorUnknownSize(new MatcherIterator(), Spliterator.ORDERED | Spliterator.NONNULL),
false);
}
}