--- /dev/null
+/*
+ * gnu/regexp/RESyntax.java
+ * Copyright (C) 1998-2001 Wes Biggs
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+package gnu.regexp;
+import java.io.Serializable;
+import java.util.BitSet;
+
+/**
+ * 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 <A HREF="mailto:wes@cacas.org">Wes Biggs</A>
+ */
+
+public final class RESyntax implements Serializable {
+ static final String DEFAULT_LINE_SEPARATOR = System.getProperty("line.separator");
+
+ private static final String SYNTAX_IS_FINAL = RE.getLocalizedMessage("syntax.final");
+
+ private BitSet bits;
+
+ // true for the constant defined syntaxes
+ private boolean isFinal = false;
+
+ private String lineSeparator = DEFAULT_LINE_SEPARATOR;
+
+ // Values for constants are bit indexes
+
+ /**
+ * Syntax bit. Backslash is an escape character in lists.
+ */
+ public static final int RE_BACKSLASH_ESCAPE_IN_LISTS = 0;
+
+ /**
+ * Syntax bit. Use \? instead of ? and \+ instead of +.
+ */
+ public static final int RE_BK_PLUS_QM = 1;
+
+ /**
+ * Syntax bit. POSIX character classes ([:...:]) in lists are allowed.
+ */
+ public static final int RE_CHAR_CLASSES = 2;
+
+ /**
+ * Syntax bit. ^ and $ are special everywhere.
+ * <B>Not implemented.</B>
+ */
+ public static final int RE_CONTEXT_INDEP_ANCHORS = 3;
+
+ /**
+ * Syntax bit. Repetition operators are only special in valid positions.
+ * <B>Not implemented.</B>
+ */
+ public static final int RE_CONTEXT_INDEP_OPS = 4;
+
+ /**
+ * Syntax bit. Repetition and alternation operators are invalid
+ * at start and end of pattern and other places.
+ * <B>Not implemented</B>.
+ */
+ public static final int RE_CONTEXT_INVALID_OPS = 5;
+
+ /**
+ * Syntax bit. Match-any-character operator (.) matches a newline.
+ */
+ public static final int RE_DOT_NEWLINE = 6;
+
+ /**
+ * Syntax bit. Match-any-character operator (.) does not match a null.
+ */
+ public static final int RE_DOT_NOT_NULL = 7;
+
+ /**
+ * Syntax bit. Intervals ({x}, {x,}, {x,y}) are allowed.
+ */
+ public static final int RE_INTERVALS = 8;
+
+ /**
+ * Syntax bit. No alternation (|), match one-or-more (+), or
+ * match zero-or-one (?) operators.
+ */
+ public static final int RE_LIMITED_OPS = 9;
+
+ /**
+ * Syntax bit. Newline is an alternation operator.
+ */
+ public static final int RE_NEWLINE_ALT = 10; // impl.
+
+ /**
+ * Syntax bit. Intervals use { } instead of \{ \}
+ */
+ public static final int RE_NO_BK_BRACES = 11;
+
+ /**
+ * Syntax bit. Grouping uses ( ) instead of \( \).
+ */
+ public static final int RE_NO_BK_PARENS = 12;
+
+ /**
+ * Syntax bit. Backreferences not allowed.
+ */
+ public static final int RE_NO_BK_REFS = 13;
+
+ /**
+ * Syntax bit. Alternation uses | instead of \|
+ */
+ public static final int RE_NO_BK_VBAR = 14;
+
+ /**
+ * Syntax bit. <B>Not implemented</B>.
+ */
+ public static final int RE_NO_EMPTY_RANGES = 15;
+
+ /**
+ * Syntax bit. An unmatched right parenthesis (')' or '\)', depending
+ * on RE_NO_BK_PARENS) will throw an exception when compiling.
+ */
+ public static final int RE_UNMATCHED_RIGHT_PAREN_ORD = 16;
+
+ /**
+ * Syntax bit. <B>Not implemented.</B>
+ */
+ public static final int RE_HAT_LISTS_NOT_NEWLINE = 17;
+
+ /**
+ * Syntax bit. Stingy matching is allowed (+?, *?, ??, {x,y}?).
+ */
+ public static final int RE_STINGY_OPS = 18;
+
+ /**
+ * Syntax bit. Allow character class escapes (\d, \D, \s, \S, \w, \W).
+ */
+ public static final int RE_CHAR_CLASS_ESCAPES = 19;
+
+ /**
+ * Syntax bit. Allow use of (?:xxx) grouping (subexpression is not saved).
+ */
+ public static final int RE_PURE_GROUPING = 20;
+
+ /**
+ * Syntax bit. Allow use of (?=xxx) and (?!xxx) apply the subexpression
+ * to the text following the current position without consuming that text.
+ */
+ public static final int RE_LOOKAHEAD = 21;
+
+ /**
+ * Syntax bit. Allow beginning- and end-of-string anchors (\A, \Z).
+ */
+ public static final int RE_STRING_ANCHORS = 22;
+
+ /**
+ * Syntax bit. Allow embedded comments, (?#comment), as in Perl5.
+ */
+ public static final int RE_COMMENTS = 23;
+
+ /**
+ * Syntax bit. Allow character class escapes within lists, as in Perl5.
+ */
+ public static final int RE_CHAR_CLASS_ESC_IN_LISTS = 24;
+
+ private static final int BIT_TOTAL = 25;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the awk utility.
+ */
+ public static final RESyntax RE_SYNTAX_AWK;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the ed utility.
+ */
+ public static final RESyntax RE_SYNTAX_ED;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the egrep utility.
+ */
+ public static final RESyntax RE_SYNTAX_EGREP;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the GNU Emacs editor.
+ */
+ public static final RESyntax RE_SYNTAX_EMACS;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the grep utility.
+ */
+ public static final RESyntax RE_SYNTAX_GREP;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the POSIX awk specification.
+ */
+ public static final RESyntax RE_SYNTAX_POSIX_AWK;
+
+ /**
+ * Predefined syntax.
+ * Emulates POSIX basic regular expression support.
+ */
+ public static final RESyntax RE_SYNTAX_POSIX_BASIC;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the POSIX egrep specification.
+ */
+ public static final RESyntax RE_SYNTAX_POSIX_EGREP;
+
+ /**
+ * Predefined syntax.
+ * Emulates POSIX extended regular expression support.
+ */
+ public static final RESyntax RE_SYNTAX_POSIX_EXTENDED;
+
+ /**
+ * Predefined syntax.
+ * Emulates POSIX basic minimal regular expressions.
+ */
+ public static final RESyntax RE_SYNTAX_POSIX_MINIMAL_BASIC;
+
+ /**
+ * Predefined syntax.
+ * Emulates POSIX extended minimal regular expressions.
+ */
+ public static final RESyntax RE_SYNTAX_POSIX_MINIMAL_EXTENDED;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in the sed utility.
+ */
+ public static final RESyntax RE_SYNTAX_SED;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in Larry Wall's perl, version 4,
+ */
+ public static final RESyntax RE_SYNTAX_PERL4;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in Larry Wall's perl, version 4,
+ * using single line mode (/s modifier).
+ */
+ public static final RESyntax RE_SYNTAX_PERL4_S; // single line mode (/s)
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in Larry Wall's perl, version 5.
+ */
+ public static final RESyntax RE_SYNTAX_PERL5;
+
+ /**
+ * Predefined syntax.
+ * Emulates regular expression support in Larry Wall's perl, version 5,
+ * using single line mode (/s modifier).
+ */
+ public static final RESyntax RE_SYNTAX_PERL5_S;
+
+ static {
+ // Define syntaxes
+
+ RE_SYNTAX_EMACS = new RESyntax().makeFinal();
+
+ RESyntax RE_SYNTAX_POSIX_COMMON = new RESyntax()
+ .set(RE_CHAR_CLASSES)
+ .set(RE_DOT_NEWLINE)
+ .set(RE_DOT_NOT_NULL)
+ .set(RE_INTERVALS)
+ .set(RE_NO_EMPTY_RANGES)
+ .makeFinal();
+
+ RE_SYNTAX_POSIX_BASIC = new RESyntax(RE_SYNTAX_POSIX_COMMON)
+ .set(RE_BK_PLUS_QM)
+ .makeFinal();
+
+ RE_SYNTAX_POSIX_EXTENDED = new RESyntax(RE_SYNTAX_POSIX_COMMON)
+ .set(RE_CONTEXT_INDEP_ANCHORS)
+ .set(RE_CONTEXT_INDEP_OPS)
+ .set(RE_NO_BK_BRACES)
+ .set(RE_NO_BK_PARENS)
+ .set(RE_NO_BK_VBAR)
+ .set(RE_UNMATCHED_RIGHT_PAREN_ORD)
+ .makeFinal();
+
+ RE_SYNTAX_AWK = new RESyntax()
+ .set(RE_BACKSLASH_ESCAPE_IN_LISTS)
+ .set(RE_DOT_NOT_NULL)
+ .set(RE_NO_BK_PARENS)
+ .set(RE_NO_BK_REFS)
+ .set(RE_NO_BK_VBAR)
+ .set(RE_NO_EMPTY_RANGES)
+ .set(RE_UNMATCHED_RIGHT_PAREN_ORD)
+ .makeFinal();
+
+ RE_SYNTAX_POSIX_AWK = new RESyntax(RE_SYNTAX_POSIX_EXTENDED)
+ .set(RE_BACKSLASH_ESCAPE_IN_LISTS)
+ .makeFinal();
+
+ RE_SYNTAX_GREP = new RESyntax()
+ .set(RE_BK_PLUS_QM)
+ .set(RE_CHAR_CLASSES)
+ .set(RE_HAT_LISTS_NOT_NEWLINE)
+ .set(RE_INTERVALS)
+ .set(RE_NEWLINE_ALT)
+ .makeFinal();
+
+ RE_SYNTAX_EGREP = new RESyntax()
+ .set(RE_CHAR_CLASSES)
+ .set(RE_CONTEXT_INDEP_ANCHORS)
+ .set(RE_CONTEXT_INDEP_OPS)
+ .set(RE_HAT_LISTS_NOT_NEWLINE)
+ .set(RE_NEWLINE_ALT)
+ .set(RE_NO_BK_PARENS)
+ .set(RE_NO_BK_VBAR)
+ .makeFinal();
+
+ RE_SYNTAX_POSIX_EGREP = new RESyntax(RE_SYNTAX_EGREP)
+ .set(RE_INTERVALS)
+ .set(RE_NO_BK_BRACES)
+ .makeFinal();
+
+ /* P1003.2/D11.2, section 4.20.7.1, lines 5078ff. */
+
+ RE_SYNTAX_ED = new RESyntax(RE_SYNTAX_POSIX_BASIC)
+ .makeFinal();
+
+ RE_SYNTAX_SED = new RESyntax(RE_SYNTAX_POSIX_BASIC)
+ .makeFinal();
+
+ RE_SYNTAX_POSIX_MINIMAL_BASIC = new RESyntax(RE_SYNTAX_POSIX_COMMON)
+ .set(RE_LIMITED_OPS)
+ .makeFinal();
+
+ /* Differs from RE_SYNTAX_POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS
+ replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added. */
+
+ RE_SYNTAX_POSIX_MINIMAL_EXTENDED = new RESyntax(RE_SYNTAX_POSIX_COMMON)
+ .set(RE_CONTEXT_INDEP_ANCHORS)
+ .set(RE_CONTEXT_INVALID_OPS)
+ .set(RE_NO_BK_BRACES)
+ .set(RE_NO_BK_PARENS)
+ .set(RE_NO_BK_REFS)
+ .set(RE_NO_BK_VBAR)
+ .set(RE_UNMATCHED_RIGHT_PAREN_ORD)
+ .makeFinal();
+
+ /* There is no official Perl spec, but here's a "best guess" */
+
+ RE_SYNTAX_PERL4 = new RESyntax()
+ .set(RE_BACKSLASH_ESCAPE_IN_LISTS)
+ .set(RE_CONTEXT_INDEP_ANCHORS)
+ .set(RE_CONTEXT_INDEP_OPS) // except for '{', apparently
+ .set(RE_INTERVALS)
+ .set(RE_NO_BK_BRACES)
+ .set(RE_NO_BK_PARENS)
+ .set(RE_NO_BK_VBAR)
+ .set(RE_NO_EMPTY_RANGES)
+ .set(RE_CHAR_CLASS_ESCAPES) // \d,\D,\w,\W,\s,\S
+ .makeFinal();
+
+ RE_SYNTAX_PERL4_S = new RESyntax(RE_SYNTAX_PERL4)
+ .set(RE_DOT_NEWLINE)
+ .makeFinal();
+
+ RE_SYNTAX_PERL5 = new RESyntax(RE_SYNTAX_PERL4)
+ .set(RE_PURE_GROUPING) // (?:)
+ .set(RE_STINGY_OPS) // *?,??,+?,{}?
+ .set(RE_LOOKAHEAD) // (?=)(?!)
+ .set(RE_STRING_ANCHORS) // \A,\Z
+ .set(RE_CHAR_CLASS_ESC_IN_LISTS)// \d,\D,\w,\W,\s,\S within []
+ .set(RE_COMMENTS) // (?#)
+ .makeFinal();
+
+ RE_SYNTAX_PERL5_S = new RESyntax(RE_SYNTAX_PERL5)
+ .set(RE_DOT_NEWLINE)
+ .makeFinal();
+ }
+
+ /**
+ * Construct a new syntax object with all bits turned off.
+ * This is equivalent to RE_SYNTAX_EMACS.
+ */
+ public RESyntax() {
+ bits = new BitSet(BIT_TOTAL);
+ }
+
+ /**
+ * 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.
+ *
+ * @return this object for convenient chaining
+ */
+ public RESyntax makeFinal() {
+ isFinal = true;
+ return this;
+ }
+
+ /**
+ * Construct a new syntax object with all bits set the same
+ * as the other syntax.
+ */
+ public RESyntax(RESyntax other) {
+ bits = (BitSet) other.bits.clone();
+ }
+
+ /**
+ * Check if a given bit is set in this syntax.
+ */
+ public boolean get(int index) {
+ return bits.get(index);
+ }
+
+ /**
+ * Set a given bit in this syntax.
+ *
+ * @param index the constant (RESyntax.RE_xxx) bit to set.
+ * @return a reference to this object for easy chaining.
+ */
+ public RESyntax set(int index) {
+ if (isFinal) throw new IllegalAccessError(SYNTAX_IS_FINAL);
+ bits.set(index);
+ return this;
+ }
+
+ /**
+ * Clear a given bit in this syntax.
+ *
+ * @param index the constant (RESyntax.RE_xxx) bit to clear.
+ * @return a reference to this object for easy chaining.
+ */
+ public RESyntax clear(int index) {
+ if (isFinal) throw new IllegalAccessError(SYNTAX_IS_FINAL);
+ bits.clear(index);
+ return this;
+ }
+
+ /**
+ * 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.
+ *
+ * @return this object for convenient chaining
+ */
+ public RESyntax setLineSeparator(String aSeparator) {
+ if (isFinal) throw new IllegalAccessError(SYNTAX_IS_FINAL);
+ lineSeparator = aSeparator;
+ return this;
+ }
+
+ /**
+ * Returns the currently active line separator string. The default
+ * is the platform-dependent system property "line.separator".
+ */
+ public String getLineSeparator() {
+ return lineSeparator;
+ }
+}
projects / org.ibex.core.git / blobdiff