Package gnu.regexp

Class RESyntax

java.lang.Object
gnu.regexp.RESyntax
All Implemented Interfaces:
Serializable

public final class RESyntax extends Object implements Serializable
An RESyntax specifies the way a regular expression will be compiled. This class provides a number of predefined useful constants for emulating popular regular expression syntaxes. Additionally the user may construct his or her own syntax, using any combination of the syntax bit constants. The syntax is an optional argument to any of the matching methods on class RE.
Author:
Wes Biggs
See Also:
  • Field Details

    • DEFAULT_LINE_SEPARATOR

      static final String DEFAULT_LINE_SEPARATOR
    • RE_BACKSLASH_ESCAPE_IN_LISTS

      public static final int RE_BACKSLASH_ESCAPE_IN_LISTS
      Syntax bit. Backslash is an escape character in lists.
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    • RE_BK_PLUS_QM

      public static final int RE_BK_PLUS_QM
      Syntax bit. Use \? instead of ? and \+ instead of +.
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    • RE_CHAR_CLASSES

      public static final int RE_CHAR_CLASSES
      Syntax bit. POSIX character classes ([:...:]) in lists are allowed.
      See Also:
    • RE_CONTEXT_INDEP_ANCHORS

      public static final int RE_CONTEXT_INDEP_ANCHORS
      Syntax bit. ^ and $ are special everywhere. Not implemented.
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    • RE_CONTEXT_INDEP_OPS

      public static final int RE_CONTEXT_INDEP_OPS
      Syntax bit. Repetition operators are only special in valid positions. Not implemented.
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    • RE_CONTEXT_INVALID_OPS

      public static final int RE_CONTEXT_INVALID_OPS
      Syntax bit. Repetition and alternation operators are invalid at start and end of pattern and other places. Not implemented.
      See Also:
    • RE_DOT_NEWLINE

      public static final int RE_DOT_NEWLINE
      Syntax bit. Match-any-character operator (.) matches a newline.
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    • RE_DOT_NOT_NULL

      public static final int RE_DOT_NOT_NULL
      Syntax bit. Match-any-character operator (.) does not match a null.
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    • RE_INTERVALS

      public static final int RE_INTERVALS
      Syntax bit. Intervals ({x}, {x,}, {x,y}) are allowed.
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    • RE_LIMITED_OPS

      public static final int RE_LIMITED_OPS
      Syntax bit. No alternation (|), match one-or-more (+), or match zero-or-one (?) operators.
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    • RE_NEWLINE_ALT

      public static final int RE_NEWLINE_ALT
      Syntax bit. Newline is an alternation operator.
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    • RE_NO_BK_BRACES

      public static final int RE_NO_BK_BRACES
      Syntax bit. Intervals use { } instead of \{ \}
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    • RE_NO_BK_PARENS

      public static final int RE_NO_BK_PARENS
      Syntax bit. Grouping uses ( ) instead of \( \).
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    • RE_NO_BK_REFS

      public static final int RE_NO_BK_REFS
      Syntax bit. Backreferences not allowed.
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    • RE_NO_BK_VBAR

      public static final int RE_NO_BK_VBAR
      Syntax bit. Alternation uses | instead of \|
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    • RE_NO_EMPTY_RANGES

      public static final int RE_NO_EMPTY_RANGES
      Syntax bit. Not implemented.
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    • RE_UNMATCHED_RIGHT_PAREN_ORD

      public static final int RE_UNMATCHED_RIGHT_PAREN_ORD
      Syntax bit. An unmatched right parenthesis (')' or '\)', depending on RE_NO_BK_PARENS) will throw an exception when compiling.
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    • RE_HAT_LISTS_NOT_NEWLINE

      public static final int RE_HAT_LISTS_NOT_NEWLINE
      Syntax bit. Not implemented.
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    • RE_STINGY_OPS

      public static final int RE_STINGY_OPS
      Syntax bit. Stingy matching is allowed (+?, *?, ??, {x,y}?).
      See Also:
    • RE_CHAR_CLASS_ESCAPES

      public static final int RE_CHAR_CLASS_ESCAPES
      Syntax bit. Allow character class escapes (\d, \D, \s, \S, \w, \W).
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    • RE_PURE_GROUPING

      public static final int RE_PURE_GROUPING
      Syntax bit. Allow use of (?:xxx) grouping (subexpression is not saved).
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    • RE_LOOKAHEAD

      public static final int RE_LOOKAHEAD
      Syntax bit. Allow use of (?=xxx) and (?!xxx) apply the subexpression to the text following the current position without consuming that text.
      See Also:
    • RE_STRING_ANCHORS

      public static final int RE_STRING_ANCHORS
      Syntax bit. Allow beginning- and end-of-string anchors (\A, \Z).
      See Also:
    • RE_COMMENTS

      public static final int RE_COMMENTS
      Syntax bit. Allow embedded comments, (?#comment), as in Perl5.
      See Also:
    • RE_CHAR_CLASS_ESC_IN_LISTS

      public static final int RE_CHAR_CLASS_ESC_IN_LISTS
      Syntax bit. Allow character class escapes within lists, as in Perl5.
      See Also:
    • RE_SYNTAX_AWK

      public static final RESyntax RE_SYNTAX_AWK
      Predefined syntax. Emulates regular expression support in the awk utility.
    • RE_SYNTAX_ED

      public static final RESyntax RE_SYNTAX_ED
      Predefined syntax. Emulates regular expression support in the ed utility.
    • RE_SYNTAX_EGREP

      public static final RESyntax RE_SYNTAX_EGREP
      Predefined syntax. Emulates regular expression support in the egrep utility.
    • RE_SYNTAX_EMACS

      public static final RESyntax RE_SYNTAX_EMACS
      Predefined syntax. Emulates regular expression support in the GNU Emacs editor.
    • RE_SYNTAX_GREP

      public static final RESyntax RE_SYNTAX_GREP
      Predefined syntax. Emulates regular expression support in the grep utility.
    • RE_SYNTAX_POSIX_AWK

      public static final RESyntax RE_SYNTAX_POSIX_AWK
      Predefined syntax. Emulates regular expression support in the POSIX awk specification.
    • RE_SYNTAX_POSIX_BASIC

      public static final RESyntax RE_SYNTAX_POSIX_BASIC
      Predefined syntax. Emulates POSIX basic regular expression support.
    • RE_SYNTAX_POSIX_EGREP

      public static final RESyntax RE_SYNTAX_POSIX_EGREP
      Predefined syntax. Emulates regular expression support in the POSIX egrep specification.
    • RE_SYNTAX_POSIX_EXTENDED

      public static final RESyntax RE_SYNTAX_POSIX_EXTENDED
      Predefined syntax. Emulates POSIX extended regular expression support.
    • RE_SYNTAX_POSIX_MINIMAL_BASIC

      public static final RESyntax RE_SYNTAX_POSIX_MINIMAL_BASIC
      Predefined syntax. Emulates POSIX basic minimal regular expressions.
    • RE_SYNTAX_POSIX_MINIMAL_EXTENDED

      public static final RESyntax RE_SYNTAX_POSIX_MINIMAL_EXTENDED
      Predefined syntax. Emulates POSIX extended minimal regular expressions.
    • RE_SYNTAX_SED

      public static final RESyntax RE_SYNTAX_SED
      Predefined syntax. Emulates regular expression support in the sed utility.
    • RE_SYNTAX_PERL4

      public static final RESyntax RE_SYNTAX_PERL4
      Predefined syntax. Emulates regular expression support in Larry Wall's perl, version 4,
    • RE_SYNTAX_PERL4_S

      public static final RESyntax RE_SYNTAX_PERL4_S
      Predefined syntax. Emulates regular expression support in Larry Wall's perl, version 4, using single line mode (/s modifier).
    • RE_SYNTAX_PERL5

      public static final RESyntax RE_SYNTAX_PERL5
      Predefined syntax. Emulates regular expression support in Larry Wall's perl, version 5.
    • RE_SYNTAX_PERL5_S

      public static final RESyntax RE_SYNTAX_PERL5_S
      Predefined syntax. Emulates regular expression support in Larry Wall's perl, version 5, using single line mode (/s modifier).
  • Constructor Details

    • RESyntax

      public RESyntax()
      Construct a new syntax object with all bits turned off. This is equivalent to RE_SYNTAX_EMACS.
    • RESyntax

      public RESyntax(RESyntax other)
      Construct a new syntax object with all bits set the same as the other syntax.
  • Method Details

    • makeFinal

      public RESyntax makeFinal()
      Called internally when constructing predefined syntaxes so their interpretation cannot vary. Conceivably useful for your syntaxes as well. Causes IllegalAccessError to be thrown if any attempt to modify the syntax is made.
      Returns:
      this object for convenient chaining
    • get

      public boolean get(int index)
      Check if a given bit is set in this syntax.
    • set

      public RESyntax set(int index)
      Set a given bit in this syntax.
      Parameters:
      index - the constant (RESyntax.RE_xxx) bit to set.
      Returns:
      a reference to this object for easy chaining.
    • clear

      public RESyntax clear(int index)
      Clear a given bit in this syntax.
      Parameters:
      index - the constant (RESyntax.RE_xxx) bit to clear.
      Returns:
      a reference to this object for easy chaining.
    • setLineSeparator

      public RESyntax setLineSeparator(String aSeparator)
      Changes the line separator string for regular expressions created using this RESyntax. The default separator is the value returned by the system property "line.separator", which should be correct when reading platform-specific files from a filesystem. However, many programs may collect input from sources where the line separator is differently specified (for example, in the applet environment, the text box widget interprets line breaks as single-character newlines, regardless of the host platform. Note that setting the line separator to a character or characters that have specific meaning within the current syntax can cause unexpected chronosynclastic infundibula.
      Returns:
      this object for convenient chaining
    • getLineSeparator

      public String getLineSeparator()
      Returns the currently active line separator string. The default is the platform-dependent system property "line.separator".