michael@0: /*
michael@0:  * ====================================================================
michael@0:  * Licensed to the Apache Software Foundation (ASF) under one
michael@0:  * or more contributor license agreements.  See the NOTICE file
michael@0:  * distributed with this work for additional information
michael@0:  * regarding copyright ownership.  The ASF licenses this file
michael@0:  * to you under the Apache License, Version 2.0 (the
michael@0:  * "License"); you may not use this file except in compliance
michael@0:  * with the License.  You may obtain a copy of the License at
michael@0:  *
michael@0:  *   http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing,
michael@0:  * software distributed under the License is distributed on an
michael@0:  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
michael@0:  * KIND, either express or implied.  See the License for the
michael@0:  * specific language governing permissions and limitations
michael@0:  * under the License.
michael@0:  * ====================================================================
michael@0:  *
michael@0:  * This software consists of voluntary contributions made by many
michael@0:  * individuals on behalf of the Apache Software Foundation.  For more
michael@0:  * information on the Apache Software Foundation, please see
michael@0:  * <http://www.apache.org/>.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: package ch.boye.httpclientandroidlib.client.methods;
michael@0: 
michael@0: import java.net.URI;
michael@0: import java.util.HashSet;
michael@0: import java.util.Set;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.annotation.NotThreadSafe;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.Header;
michael@0: import ch.boye.httpclientandroidlib.HeaderElement;
michael@0: import ch.boye.httpclientandroidlib.HeaderIterator;
michael@0: import ch.boye.httpclientandroidlib.HttpResponse;
michael@0: 
michael@0: /**
michael@0:  * HTTP OPTIONS method.
michael@0:  * <p>
michael@0:  * The HTTP OPTIONS method is defined in section 9.2 of
michael@0:  * <a href="http://www.ietf.org/rfc/rfc2616.txt">RFC2616</a>:
michael@0:  * <blockquote>
michael@0:  *  The OPTIONS method represents a request for information about the
michael@0:  *  communication options available on the request/response chain
michael@0:  *  identified by the Request-URI. This method allows the client to
michael@0:  *  determine the options and/or requirements associated with a resource,
michael@0:  *  or the capabilities of a server, without implying a resource action
michael@0:  *  or initiating a resource retrieval.
michael@0:  * </blockquote>
michael@0:  * </p>
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: @NotThreadSafe
michael@0: public class HttpOptions extends HttpRequestBase {
michael@0: 
michael@0:     public final static String METHOD_NAME = "OPTIONS";
michael@0: 
michael@0:     public HttpOptions() {
michael@0:         super();
michael@0:     }
michael@0: 
michael@0:     public HttpOptions(final URI uri) {
michael@0:         super();
michael@0:         setURI(uri);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @throws IllegalArgumentException if the uri is invalid.
michael@0:      */
michael@0:     public HttpOptions(final String uri) {
michael@0:         super();
michael@0:         setURI(URI.create(uri));
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public String getMethod() {
michael@0:         return METHOD_NAME;
michael@0:     }
michael@0: 
michael@0:     public Set<String> getAllowedMethods(final HttpResponse response) {
michael@0:         if (response == null) {
michael@0:             throw new IllegalArgumentException("HTTP response may not be null");
michael@0:         }
michael@0: 
michael@0:         HeaderIterator it = response.headerIterator("Allow");
michael@0:         Set<String> methods = new HashSet<String>();
michael@0:         while (it.hasNext()) {
michael@0:             Header header = it.nextHeader();
michael@0:             HeaderElement[] elements = header.getElements();
michael@0:             for (HeaderElement element : elements) {
michael@0:                 methods.add(element.getName());
michael@0:             }
michael@0:         }
michael@0:         return methods;
michael@0:     }
michael@0: 
michael@0: }