--- /dev/null
+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. 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
+ */
+
+package org.opendaylight.controller.filtervalve.cors.model;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.collect.Maps.immutableEntry;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.TreeMap;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Match incoming URL with user defined patterns according to servlet specification.
+ * In the Web application deployment descriptor, the following syntax is used to define mappings:
+ * <ul>
+ * <li>A string beginning with a ‘/’ character and ending with a ‘/*’ suffix is used for path mapping.</li>
+ * <li>A string beginning with a ‘*.’ prefix is used as an extension mapping.</li>
+ * <li>All other strings are used for exact matches only.</li>
+ * </ul>
+ */
+public class UrlMatcher<FILTER> {
+ private static final Logger logger = LoggerFactory.getLogger(UrlMatcher.class);
+ // order index for each FILTER is kept as Entry.value
+ private final Map<String, Entry<FILTER, Integer>> prefixMap = new HashMap<>(); // contains patterns ending with '/*', '*' is stripped from each key
+ private final Map<String, Entry<FILTER, Integer>> suffixMap = new HashMap<>(); // contains patterns starting with '*.' prefix, '*' is stripped from each key
+ private final Map<String, Entry<FILTER, Integer>> exactMatchMap = new HashMap<>(); // contains exact matches only
+
+ /**
+ * @param patternMap order preserving map containing path info pattern as key
+ */
+ public UrlMatcher(LinkedHashMap<String, FILTER> patternMap) {
+ int idx = 0;
+ for (Entry<String, FILTER> entry : patternMap.entrySet()) {
+ idx++;
+ String pattern = checkNotNull(entry.getKey());
+ FILTER value = entry.getValue();
+ Entry<FILTER, Integer> valueWithIdx = immutableEntry(value, idx);
+ if (pattern.startsWith("/") && pattern.endsWith("/*")) {
+ pattern = pattern.substring(0, pattern.length() - 1);
+ prefixMap.put(pattern, valueWithIdx);
+ } else if (pattern.startsWith("*.")) {
+ pattern = pattern.substring(1);
+ suffixMap.put(pattern, valueWithIdx);
+ } else {
+ exactMatchMap.put(pattern, valueWithIdx);
+ }
+ }
+ }
+
+ /**
+ * Find filters matching path
+ *
+ * @param pathInfo as returned by request.getPathInfo()
+ * @return list of matching filters
+ */
+ public List<FILTER> findMatchingFilters(String pathInfo) {
+ checkNotNull(pathInfo);
+ TreeMap<Integer, FILTER> sortedMap = new TreeMap<>();
+ // add matching prefixes
+ for (Entry<String, Entry<FILTER, Integer>> prefixEntry : prefixMap.entrySet()) {
+ if (pathInfo.startsWith(prefixEntry.getKey())) {
+ put(sortedMap, prefixEntry.getValue());
+ }
+ }
+ // add matching suffixes
+ for (Entry<String, Entry<FILTER, Integer>> suffixEntry : suffixMap.entrySet()) {
+ if (pathInfo.endsWith(suffixEntry.getKey())) {
+ put(sortedMap, suffixEntry.getValue());
+ }
+ }
+ // add exact match
+ Entry<FILTER, Integer> exactMatch = exactMatchMap.get(pathInfo);
+ if (exactMatch != null) {
+ put(sortedMap, exactMatch);
+ }
+ ArrayList<FILTER> filters = new ArrayList<>(sortedMap.values());
+ logger.trace("Matching filters for path {} are {}", pathInfo, filters);
+ return filters;
+ }
+
+ private void put(TreeMap<Integer, FILTER> sortedMap, Entry<FILTER, Integer> entry) {
+ sortedMap.put(entry.getValue(), entry.getKey());
+ }
+}