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1   /*
2    * ====================================================================
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *   http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing,
14   * software distributed under the License is distributed on an
15   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16   * KIND, either express or implied.  See the License for the
17   * specific language governing permissions and limitations
18   * under the License.
19   * ====================================================================
20   *
21   * This software consists of voluntary contributions made by many
22   * individuals on behalf of the Apache Software Foundation.  For more
23   * information on the Apache Software Foundation, please see
24   * <http://www.apache.org/>.
25   *
26   */
27  
28  package org.apache.http.protocol;
29  
30  import java.util.Map;
31  
32  import org.apache.http.annotation.ThreadSafe;
33  
34  /**
35   * Maintains a map of HTTP request handlers keyed by a request URI pattern.
36   * <br>
37   * Patterns may have three formats:
38   * <ul>
39   *   <li><code>*</code></li>
40   *   <li><code>*&lt;uri&gt;</code></li>
41   *   <li><code>&lt;uri&gt;*</code></li>
42   * </ul>
43   * <br>
44   * This class can be used to resolve an instance of
45   * {@link HttpRequestHandler} matching a particular request URI. Usually the
46   * resolved request handler will be used to process the request with the
47   * specified request URI.
48   *
49   * @since 4.0
50   */
51  @ThreadSafe // provided injected dependencies are thread-safe
52  public class HttpRequestHandlerRegistry implements HttpRequestHandlerResolver {
53  
54      private final UriPatternMatcher<HttpRequestHandler> matcher;
55  
56      public HttpRequestHandlerRegistry() {
57          matcher = new UriPatternMatcher<HttpRequestHandler>();
58      }
59  
60      /**
61       * Registers the given {@link HttpRequestHandler} as a handler for URIs
62       * matching the given pattern.
63       *
64       * @param pattern the pattern to register the handler for.
65       * @param handler the handler.
66       */
67      public void register(final String pattern, final HttpRequestHandler handler) {
68          if (pattern == null) {
69              throw new IllegalArgumentException("URI request pattern may not be null");
70          }
71          if (handler == null) {
72              throw new IllegalArgumentException("Request handler may not be null");
73          }
74          matcher.register(pattern, handler);
75      }
76  
77      /**
78       * Removes registered handler, if exists, for the given pattern.
79       *
80       * @param pattern the pattern to unregister the handler for.
81       */
82      public void unregister(final String pattern) {
83          matcher.unregister(pattern);
84      }
85  
86      /**
87       * Sets handlers from the given map.
88       * @param map the map containing handlers keyed by their URI patterns.
89       */
90      public void setHandlers(final Map<String, HttpRequestHandler> map) {
91          matcher.setObjects(map);
92      }
93  
94      /**
95       * Get the handler map.
96       * @return The map of handlers and their associated URI patterns.
97       *
98       * @since 4.2
99       */
100     public Map<String, HttpRequestHandler> getHandlers() {
101         return matcher.getObjects();
102     }
103 
104     public HttpRequestHandler lookup(final String requestURI) {
105         return matcher.lookup(requestURI);
106     }
107 
108 }