--- /dev/null
+/*
+ * gnu/regexp/REMatch.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;
+
+/**
+ * An instance of this class represents a match
+ * completed by a gnu.regexp matching function. It can be used
+ * to obtain relevant information about the location of a match
+ * or submatch.
+ *
+ * @author <A HREF="mailto:wes@cacas.org">Wes Biggs</A>
+ */
+public final class REMatch implements Serializable, Cloneable {
+ private String matchedText;
+
+ // These variables are package scope for fast access within the engine
+ int eflags; // execution flags this match was made using
+
+ // Offset in source text where match was tried. This is zero-based;
+ // the actual position in the source text is given by (offset + anchor).
+ int offset;
+
+ // Anchor position refers to the index into the source input
+ // at which the matching operation began.
+ // This is also useful for the ANCHORINDEX option.
+ int anchor;
+
+ // Package scope; used by RE.
+ int index; // used while matching to mark current match position in input
+ int[] start; // start positions (relative to offset) for each (sub)exp.
+ int[] end; // end positions for the same
+ REMatch next; // other possibility (to avoid having to use arrays)
+
+ public Object clone() {
+ try {
+ REMatch copy = (REMatch) super.clone();
+ copy.next = null;
+
+ copy.start = (int[]) start.clone();
+ copy.end = (int[]) end.clone();
+
+ return copy;
+ } catch (CloneNotSupportedException e) {
+ throw new Error(); // doesn't happen
+ }
+ }
+
+ void assignFrom(REMatch other) {
+ start = other.start;
+ end = other.end;
+ index = other.index;
+ // need to deep clone?
+ next = other.next;
+ }
+
+ REMatch(int subs, int anchor, int eflags) {
+ start = new int[subs+1];
+ end = new int[subs+1];
+ this.anchor = anchor;
+ this.eflags = eflags;
+ clear(anchor);
+ }
+
+ void finish(CharIndexed text) {
+ start[0] = 0;
+ StringBuffer sb = new StringBuffer();
+ int i;
+ for (i = 0; i < end[0]; i++)
+ sb.append(text.charAt(i));
+ matchedText = sb.toString();
+ for (i = 0; i < start.length; i++) {
+ // If any subexpressions didn't terminate, they don't count
+ // TODO check if this code ever gets hit
+ if ((start[i] == -1) ^ (end[i] == -1)) {
+ start[i] = -1;
+ end[i] = -1;
+ }
+ }
+ next = null; // cut off alternates
+ }
+
+ /** Clears the current match and moves the offset to the new index. */
+ void clear(int index) {
+ offset = index;
+ this.index = 0;
+ for (int i = 0; i < start.length; i++) {
+ start[i] = end[i] = -1;
+ }
+ next = null; // cut off alternates
+ }
+
+ /**
+ * Returns the string matching the pattern. This makes it convenient
+ * to write code like the following:
+ * <P>
+ * <code>
+ * REMatch myMatch = myExpression.getMatch(myString);<br>
+ * if (myMatch != null) System.out.println("Regexp found: "+myMatch);
+ * </code>
+ */
+ public String toString() {
+ return matchedText;
+ }
+
+ /**
+ * Returns the index within the input text where the match in its entirety
+ * began.
+ */
+ public int getStartIndex() {
+ return offset + start[0];
+ }
+
+ /**
+ * Returns the index within the input string where the match in
+ * its entirety ends. The return value is the next position after
+ * the end of the string; therefore, a match created by the
+ * following call:
+ *
+ * <P>
+ * <code>REMatch myMatch = myExpression.getMatch(myString);</code>
+ * <P>
+ * can be viewed (given that myMatch is not null) by creating
+ * <P>
+ * <code>String theMatch = myString.substring(myMatch.getStartIndex(),
+ * myMatch.getEndIndex());</code>
+ * <P>
+ * But you can save yourself that work, since the <code>toString()</code>
+ * method (above) does exactly that for you.
+ */
+ public int getEndIndex() {
+ return offset + end[0];
+ }
+
+ /**
+ * Returns the string matching the given subexpression. The subexpressions
+ * are indexed starting with one, not zero. That is, the subexpression
+ * identified by the first set of parentheses in a regular expression
+ * could be retrieved from an REMatch by calling match.toString(1).
+ *
+ * @param sub Index of the subexpression.
+ */
+ public String toString(int sub) {
+ if ((sub >= start.length) || (start[sub] == -1)) return "";
+ return (matchedText.substring(start[sub],end[sub]));
+ }
+
+ /**
+ * Returns the index within the input string used to generate this match
+ * where subexpression number <i>sub</i> begins, or <code>-1</code> if
+ * the subexpression does not exist. The initial position is zero.
+ *
+ * @param sub Subexpression index
+ * @deprecated Use getStartIndex(int) instead.
+ */
+ public int getSubStartIndex(int sub) {
+ if (sub >= start.length) return -1;
+ int x = start[sub];
+ return (x == -1) ? x : offset + x;
+ }
+
+ /**
+ * Returns the index within the input string used to generate this match
+ * where subexpression number <i>sub</i> begins, or <code>-1</code> if
+ * the subexpression does not exist. The initial position is zero.
+ *
+ * @param sub Subexpression index
+ * @since gnu.regexp 1.1.0
+ */
+ public int getStartIndex(int sub) {
+ if (sub >= start.length) return -1;
+ int x = start[sub];
+ return (x == -1) ? x : offset + x;
+ }
+
+ /**
+ * Returns the index within the input string used to generate this match
+ * where subexpression number <i>sub</i> ends, or <code>-1</code> if
+ * the subexpression does not exist. The initial position is zero.
+ *
+ * @param sub Subexpression index
+ * @deprecated Use getEndIndex(int) instead
+ */
+ public int getSubEndIndex(int sub) {
+ if (sub >= start.length) return -1;
+ int x = end[sub];
+ return (x == -1) ? x : offset + x;
+ }
+
+ /**
+ * Returns the index within the input string used to generate this match
+ * where subexpression number <i>sub</i> ends, or <code>-1</code> if
+ * the subexpression does not exist. The initial position is zero.
+ *
+ * @param sub Subexpression index
+ */
+ public int getEndIndex(int sub) {
+ if (sub >= start.length) return -1;
+ int x = end[sub];
+ return (x == -1) ? x : offset + x;
+ }
+
+ /**
+ * Substitute the results of this match to create a new string.
+ * This is patterned after PERL, so the tokens to watch out for are
+ * <code>$0</code> through <code>$9</code>. <code>$0</code> matches
+ * the full substring matched; <code>$<i>n</i></code> matches
+ * subexpression number <i>n</i>.
+ *
+ * @param input A string consisting of literals and <code>$<i>n</i></code> tokens.
+ */
+ public String substituteInto(String input) {
+ // a la Perl, $0 is whole thing, $1 - $9 are subexpressions
+ StringBuffer output = new StringBuffer();
+ int pos;
+ for (pos = 0; pos < input.length()-1; pos++) {
+ if ((input.charAt(pos) == '$') && (Character.isDigit(input.charAt(pos+1)))) {
+ int val = Character.digit(input.charAt(++pos),10);
+ if (val < start.length) {
+ output.append(toString(val));
+ }
+ } else output.append(input.charAt(pos));
+ }
+ if (pos < input.length()) output.append(input.charAt(pos));
+ return output.toString();
+ }
+}
projects / org.ibex.core.git / blobdiff