HttpOptions.java revision 417f3b92ba4549b2f22340e3107d869d2b9c5bb8 
1/*
2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk/module-client/src/main/java/org/apache/http/client/methods/HttpOptions.java $
3 * $Revision: 664505 $
4 * $Date: 2008-06-08 06:21:20 -0700 (Sun, 08 Jun 2008) $
5 *
6 * ====================================================================
7 * Licensed to the Apache Software Foundation (ASF) under one
8 * or more contributor license agreements.  See the NOTICE file
9 * distributed with this work for additional information
10 * regarding copyright ownership.  The ASF licenses this file
11 * to you under the Apache License, Version 2.0 (the
12 * "License"); you may not use this file except in compliance
13 * with the License.  You may obtain a copy of the License at
14 *
15 *   http://www.apache.org/licenses/LICENSE-2.0
16 *
17 * Unless required by applicable law or agreed to in writing,
18 * software distributed under the License is distributed on an
19 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
20 * KIND, either express or implied.  See the License for the
21 * specific language governing permissions and limitations
22 * under the License.
23 * ====================================================================
24 *
25 * This software consists of voluntary contributions made by many
26 * individuals on behalf of the Apache Software Foundation.  For more
27 * information on the Apache Software Foundation, please see
28 * <http://www.apache.org/>.
29 *
30 */
31
32package org.apache.http.client.methods;
33
34import java.net.URI;
35import java.util.HashSet;
36import java.util.Set;
37
38import org.apache.http.Header;
39import org.apache.http.HeaderElement;
40import org.apache.http.HeaderIterator;
41import org.apache.http.HttpResponse;
42
43/**
44 * HTTP OPTIONS method.
45 * <p>
46 * The HTTP OPTIONS method is defined in section 9.2 of
47 * <a href="http://www.ietf.org/rfc/rfc2616.txt">RFC2616</a>:
48 * <blockquote>
49 *  The OPTIONS method represents a request for information about the
50 *  communication options available on the request/response chain
51 *  identified by the Request-URI. This method allows the client to
52 *  determine the options and/or requirements associated with a resource,
53 *  or the capabilities of a server, without implying a resource action
54 *  or initiating a resource retrieval.
55 * </blockquote>
56 * </p>
57 *
58 * @version $Revision: 664505 $
59 *
60 * @since 4.0
61 */
62public class HttpOptions extends HttpRequestBase {
63
64    public final static String METHOD_NAME = "OPTIONS";
65
66    public HttpOptions() {
67        super();
68    }
69
70    public HttpOptions(final URI uri) {
71        super();
72        setURI(uri);
73    }
74
75    /**
76     * @throws IllegalArgumentException if the uri is invalid.
77     */
78    public HttpOptions(final String uri) {
79        super();
80        setURI(URI.create(uri));
81    }
82
83    @Override
84    public String getMethod() {
85        return METHOD_NAME;
86    }
87
88    public Set<String> getAllowedMethods(final HttpResponse response) {
89        if (response == null) {
90            throw new IllegalArgumentException("HTTP response may not be null");
91        }
92
93        HeaderIterator it = response.headerIterator("Allow");
94        Set<String> methods = new HashSet<String>();
95        while (it.hasNext()) {
96            Header header = it.nextHeader();
97            HeaderElement[] elements = header.getElements();
98            for (HeaderElement element : elements) {
99                methods.add(element.getName());
100            }
101        }
102        return methods;
103    }
104
105}
106