1 /* 2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/protocol/RequestUserAgent.java $ 3 * $Revision: 496070 $ 4 * $Date: 2007-01-14 04:18:34 -0800 (Sun, 14 Jan 2007) $ 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 32 package org.apache.http.protocol; 33 34 import java.io.IOException; 35 36 import org.apache.http.HttpException; 37 import org.apache.http.HttpRequest; 38 import org.apache.http.HttpRequestInterceptor; 39 import org.apache.http.params.HttpProtocolParams; 40 41 /** 42 * A request interceptor that adds a User-Agent header. 43 * 44 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a> 45 * 46 * @version $Revision: 496070 $ 47 * 48 * @since 4.0 49 */ 50 public class RequestUserAgent implements HttpRequestInterceptor { 51 RequestUserAgent()52 public RequestUserAgent() { 53 super(); 54 } 55 process(final HttpRequest request, final HttpContext context)56 public void process(final HttpRequest request, final HttpContext context) 57 throws HttpException, IOException { 58 if (request == null) { 59 throw new IllegalArgumentException("HTTP request may not be null"); 60 } 61 if (!request.containsHeader(HTTP.USER_AGENT)) { 62 String useragent = HttpProtocolParams.getUserAgent(request.getParams()); 63 if (useragent != null) { 64 request.addHeader(HTTP.USER_AGENT, useragent); 65 } 66 } 67 } 68 69 } 70