WildcardSegmentMatcher.java

/*
 * Copyright (c) 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     bstefanescu
 */
package org.eclipse.ecr.web.jaxrs.servlet.mapping;


/**
 * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
 *
 */
public class WildcardSegmentMatcher extends SegmentMatcher {

    protected final char[] pattern;


    public WildcardSegmentMatcher(String pattern) {
        this.pattern = pattern.replace("**", "*").toCharArray();
    }

    public WildcardSegmentMatcher(char[] pattern) {
        this.pattern = pattern;
    }

    @Override
    public boolean matches(String segment) {
        if (pattern.length == 0) {
            return true;
        }
        return matches(segment.toCharArray(), 0, 0);
    }


    public boolean matches(char[] segment, int soff, int poff) {
        if (poff == pattern.length) {
            // pattern consumed
            if (soff == segment.length) {
                // segment consumed too
                return true;
            }
            // segment is not yet consumed
            if (pattern[pattern.length-1] == '*') {
                // last char is a wildcard => matched
                return true;
            }
            return false;
        }
        if (soff == segment.length) {
            // segment consumed but pattern is not yet consumed
            if (poff+1 == pattern.length && pattern[poff] == '*') {
                // there is only one char remaining and it is a wildcard => matched
                return true;
            }
            return false;
        }

        if (pattern[poff] == '*') {
            // current pattern char is a wildcard - try all substrings
            for (int i = soff; i < segment.length; i++) {
                if (matches(segment, i, poff + 1)) {
                    return true;
                }
            }
            return false;
        }

        // test is the current char is matching
        if (pattern[poff] != '?' && pattern[poff] != segment[soff]) {
            return false; // not matching
        }

        // continue iteration on segments and matchers
        return matches(segment, soff + 1, poff + 1);

    }

    @Override
    public String toString() {
        return new String(pattern);
    }
}