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: package ch.boye.httpclientandroidlib.impl.client;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.annotation.Immutable;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.HeaderElement;
michael@0: import ch.boye.httpclientandroidlib.HeaderElementIterator;
michael@0: import ch.boye.httpclientandroidlib.HttpResponse;
michael@0: import ch.boye.httpclientandroidlib.conn.ConnectionKeepAliveStrategy;
michael@0: import ch.boye.httpclientandroidlib.message.BasicHeaderElementIterator;
michael@0: import ch.boye.httpclientandroidlib.protocol.HTTP;
michael@0: import ch.boye.httpclientandroidlib.protocol.HttpContext;
michael@0: 
michael@0: /**
michael@0:  * Default implementation of a strategy deciding duration
michael@0:  * that a connection can remain idle.
michael@0:  *
michael@0:  * The default implementation looks solely at the 'Keep-Alive'
michael@0:  * header's timeout token.
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: @Immutable
michael@0: public class DefaultConnectionKeepAliveStrategy implements ConnectionKeepAliveStrategy {
michael@0: 
michael@0:     public long getKeepAliveDuration(HttpResponse response, HttpContext context) {
michael@0:         if (response == null) {
michael@0:             throw new IllegalArgumentException("HTTP response may not be null");
michael@0:         }
michael@0:         HeaderElementIterator it = new BasicHeaderElementIterator(
michael@0:                 response.headerIterator(HTTP.CONN_KEEP_ALIVE));
michael@0:         while (it.hasNext()) {
michael@0:             HeaderElement he = it.nextElement();
michael@0:             String param = he.getName();
michael@0:             String value = he.getValue();
michael@0:             if (value != null && param.equalsIgnoreCase("timeout")) {
michael@0:                 try {
michael@0:                     return Long.parseLong(value) * 1000;
michael@0:                 } catch(NumberFormatException ignore) {
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0:         return -1;
michael@0:     }
michael@0: 
michael@0: }