/*
* $HeadURL: https://svn.apache.org/repos/asf/jakarta/httpcomponents/httpcore/tags/4.0-alpha2/src/java/org/apache/http/protocol/RequestExpectContinue.java $
* $Revision: 408172 $
* $Date: 2006-05-21 16:06:29 +0200 (Sun, 21 May 2006) $
*
* ====================================================================
*
* Copyright 1999-2006 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.http.protocol;
import java.io.IOException;
import org.apache.http.HttpEntity;
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpException;
import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestInterceptor;
import org.apache.http.HttpVersion;
import org.apache.http.params.HttpProtocolParams;
/**
* A request interceptor that enables the expect-continue handshake.
*
* @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
*
* @version $Revision: 408172 $
*
* @since 4.0
*/
public class RequestExpectContinue implements HttpRequestInterceptor {
public RequestExpectContinue() {
super();
}
public void process(final HttpRequest request, final HttpContext context)
throws HttpException, IOException {
if (request == null) {
throw new IllegalArgumentException("HTTP request may not be null");
}
if (request instanceof HttpEntityEnclosingRequest) {
HttpEntity entity = ((HttpEntityEnclosingRequest)request).getEntity();
// Do not send the expect header if request body is known to be empty
if (entity != null && entity.getContentLength() != 0) {
HttpVersion ver = request.getRequestLine().getHttpVersion();
if (HttpProtocolParams.useExpectContinue(request.getParams())
&& ver.greaterEquals(HttpVersion.HTTP_1_1)) {
request.addHeader(new GeneratedHeader(HTTP.EXPECT_DIRECTIVE,
HTTP.EXPECT_CONTINUE));
}
}
}
}
}