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.protocol;
michael@0: 
michael@0: import java.io.IOException;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.HttpException;
michael@0: import ch.boye.httpclientandroidlib.HttpResponse;
michael@0: import ch.boye.httpclientandroidlib.HttpResponseInterceptor;
michael@0: import ch.boye.httpclientandroidlib.HttpStatus;
michael@0: 
michael@0: /**
michael@0:  * ResponseDate is responsible for adding <code>Date<c/ode> header to the
michael@0:  * outgoing responses. This interceptor is recommended for server side protocol
michael@0:  * processors.
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: public class ResponseDate implements HttpResponseInterceptor {
michael@0: 
michael@0:     private static final HttpDateGenerator DATE_GENERATOR = new HttpDateGenerator();
michael@0: 
michael@0:     public ResponseDate() {
michael@0:         super();
michael@0:     }
michael@0: 
michael@0:     public void process(final HttpResponse response, final HttpContext context)
michael@0:             throws HttpException, IOException {
michael@0:         if (response == null) {
michael@0:             throw new IllegalArgumentException
michael@0:                 ("HTTP response may not be null.");
michael@0:         }
michael@0:         int status = response.getStatusLine().getStatusCode();
michael@0:         if ((status >= HttpStatus.SC_OK) &&
michael@0:             !response.containsHeader(HTTP.DATE_HEADER)) {
michael@0:             String httpdate = DATE_GENERATOR.getCurrentDate();
michael@0:             response.setHeader(HTTP.DATE_HEADER, httpdate);
michael@0:         }
michael@0:     }
michael@0: 
michael@0: }