/*
* Copyright (C) 2010 eXo Platform SAS.
*
* This 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 software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.exoplatform.web.controller.router;
import org.exoplatform.web.controller.regexp.GroupType;
import org.exoplatform.web.controller.regexp.RENode;
import org.exoplatform.web.controller.regexp.REVisitor;
/**
* The route escaper transformer a regular expression with the following rules:
* <ul>
* <li>substitute any char occurence of the source <i>s</i> by the destination <i>d</i></li>
* <li>replace the <i>any</i> by the negated destination character <i>[^]</i></li>
* <li>append <i>&&[^s]</i> to any top character class</li>
* </ul>
*
* A few examples with <i>/</i> replaced by <i>_</i>:
*
* <ul>
* <li><i>/</i> becomes <i>_</i></li>
* <li><i>.</i> becomes <i>[^/]</i></li>
* <li><i>[a/]</i> becomes <i>[a_&[^/]]</i></li>
* <li><i>[,-1]</i> becomes <i>[,-.0-1_&&[^/]]</i></li>
* </ul>
*
* @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
* @version $Revision$
*/
public class RouteEscaper extends REVisitor<MalformedRouteException> {
/** . */
private final char src;
/** . */
private final char dst;
public RouteEscaper(char src, char dst) {
this.src = src;
this.dst = dst;
}
@Override
protected void visit(RENode.Char expr) throws MalformedRouteException {
if (expr.getValue() == src) {
expr.setValue(dst);
}
}
@Override
protected void visit(RENode.Group expr) throws MalformedRouteException {
if (expr.getType() == GroupType.CAPTURING_GROUP) {
expr.setType(GroupType.NON_CAPTURING_GROUP);
}
super.visit(expr);
}
@Override
protected void visit(RENode.Any expr) throws MalformedRouteException {
RENode.CharacterClass repl = new RENode.CharacterClass(new RENode.CharacterClassExpr.Not(
new RENode.CharacterClassExpr.Char('/')));
repl.setQuantifier(expr.getQuantifier());
expr.replaceBy(repl);
}
@Override
protected void visit(RENode.CharacterClass expr) throws MalformedRouteException {
RENode.CharacterClassExpr ccExpr = expr.getExpr();
ccExpr = ccExpr.replace(src, dst);
// RENode.CharacterClassExpr.And ccRepl = new RENode.CharacterClassExpr.And(null, new RENode.CharacterClassExpr.Not(new
// RENode.CharacterClassExpr.Char('/')));
// ccExpr.replaceBy(ccRepl);
// ccRepl.setLeft(ccExpr);
}
}