105 lines
3.6 KiB
Java
105 lines
3.6 KiB
Java
/* gnu/regexp/RETokenWordBoundary.java
|
|
Copyright (C) 2001, 2004 Free Software Foundation, Inc.
|
|
|
|
This file is part of GNU Classpath.
|
|
|
|
GNU Classpath is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
GNU Classpath 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 for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
|
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
02110-1301 USA.
|
|
|
|
Linking this library statically or dynamically with other modules is
|
|
making a combined work based on this library. Thus, the terms and
|
|
conditions of the GNU General Public License cover the whole
|
|
combination.
|
|
|
|
As a special exception, the copyright holders of this library give you
|
|
permission to link this library with independent modules to produce an
|
|
executable, regardless of the license terms of these independent
|
|
modules, and to copy and distribute the resulting executable under
|
|
terms of your choice, provided that you also meet, for each linked
|
|
independent module, the terms and conditions of the license of that
|
|
module. An independent module is a module which is not derived from
|
|
or based on this library. If you modify this library, you may extend
|
|
this exception to your version of the library, but you are not
|
|
obligated to do so. If you do not wish to do so, delete this
|
|
exception statement from your version. */
|
|
|
|
|
|
package gnu.regexp;
|
|
|
|
/**
|
|
* Represents a combination lookahead/lookbehind for POSIX [:alnum:].
|
|
*/
|
|
final class RETokenWordBoundary extends REToken {
|
|
private boolean negated;
|
|
private int where;
|
|
static final int BEGIN = 1;
|
|
static final int END = 2;
|
|
|
|
RETokenWordBoundary(int subIndex, int where, boolean negated) {
|
|
super(subIndex);
|
|
this.where = where;
|
|
this.negated = negated;
|
|
}
|
|
|
|
boolean match(CharIndexed input, REMatch mymatch) {
|
|
// Word boundary means input[index-1] was a word character
|
|
// and input[index] is not, or input[index] is a word character
|
|
// and input[index-1] was not
|
|
// In the string "one two three", these positions match:
|
|
// |o|n|e| |t|w|o| |t|h|r|e|e|
|
|
// ^ ^ ^ ^ ^ ^
|
|
boolean after = false; // is current character a letter or digit?
|
|
boolean before = false; // is previous character a letter or digit?
|
|
char ch;
|
|
|
|
// TODO: Also check REG_ANCHORINDEX vs. anchor
|
|
if (((mymatch.eflags & RE.REG_ANCHORINDEX) != RE.REG_ANCHORINDEX)
|
|
|| (mymatch.offset + mymatch.index > mymatch.anchor)) {
|
|
if ((ch = input.charAt(mymatch.index - 1)) != CharIndexed.OUT_OF_BOUNDS) {
|
|
before = Character.isLetterOrDigit(ch) || (ch == '_');
|
|
}
|
|
}
|
|
|
|
if ((ch = input.charAt(mymatch.index)) != CharIndexed.OUT_OF_BOUNDS) {
|
|
after = Character.isLetterOrDigit(ch) || (ch == '_');
|
|
}
|
|
|
|
// if (before) and (!after), we're at end (\>)
|
|
// if (after) and (!before), we're at beginning (\<)
|
|
boolean doNext = false;
|
|
|
|
if ((where & BEGIN) == BEGIN) {
|
|
doNext = after && !before;
|
|
}
|
|
if ((where & END) == END) {
|
|
doNext ^= before && !after;
|
|
}
|
|
|
|
if (negated) doNext = !doNext;
|
|
|
|
return (doNext ? next(input, mymatch) : false);
|
|
}
|
|
|
|
void dump(StringBuffer os) {
|
|
if (where == (BEGIN | END)) {
|
|
os.append( negated ? "\\B" : "\\b" );
|
|
} else if (where == BEGIN) {
|
|
os.append("\\<");
|
|
} else {
|
|
os.append("\\>");
|
|
}
|
|
}
|
|
}
|