001/*
002 * ====================================================================
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 *   http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing,
014 * software distributed under the License is distributed on an
015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
016 * KIND, either express or implied.  See the License for the
017 * specific language governing permissions and limitations
018 * under the License.
019 * ====================================================================
020 *
021 * This software consists of voluntary contributions made by many
022 * individuals on behalf of the Apache Software Foundation.  For more
023 * information on the Apache Software Foundation, please see
024 * <http://www.apache.org/>.
025 *
026 */
027
028package org.apache.http;
029
030import java.io.IOException;
031
032/**
033 * A client-side HTTP connection, which can be used for sending
034 * requests and receiving responses.
035 *
036 * @since 4.0
037 */
038public interface HttpClientConnection extends HttpConnection {
039
040    /**
041     * Checks if response data is available from the connection. May wait for
042     * the specified time until some data becomes available. Note that some
043     * implementations may completely ignore the timeout parameter.
044     *
045     * @param timeout the maximum time in milliseconds to wait for data
046     * @return true if data is available; false if there was no data available
047     *         even after waiting for {@code timeout} milliseconds.
048     * @throws IOException if an error happens on the connection
049     */
050    boolean isResponseAvailable(int timeout)
051        throws IOException;
052
053    /**
054     * Sends the request line and all headers over the connection.
055     * @param request the request whose headers to send.
056     * @throws HttpException in case of HTTP protocol violation
057     * @throws IOException in case of an I/O error
058     */
059    void sendRequestHeader(HttpRequest request)
060        throws HttpException, IOException;
061
062    /**
063     * Sends the request entity over the connection.
064     * @param request the request whose entity to send.
065     * @throws HttpException in case of HTTP protocol violation
066     * @throws IOException in case of an I/O error
067     */
068    void sendRequestEntity(HttpEntityEnclosingRequest request)
069        throws HttpException, IOException;
070
071    /**
072     * Receives the request line and headers of the next response available from
073     * this connection. The caller should examine the HttpResponse object to
074     * find out if it should try to receive a response entity as well.
075     *
076     * @return a new HttpResponse object with status line and headers
077     *         initialized.
078     * @throws HttpException in case of HTTP protocol violation
079     * @throws IOException in case of an I/O error
080     */
081    HttpResponse receiveResponseHeader()
082        throws HttpException, IOException;
083
084    /**
085     * Receives the next response entity available from this connection and
086     * attaches it to an existing HttpResponse object.
087     *
088     * @param response the response to attach the entity to
089     * @throws HttpException in case of HTTP protocol violation
090     * @throws IOException in case of an I/O error
091     */
092    void receiveResponseEntity(HttpResponse response)
093        throws HttpException, IOException;
094
095    /**
096     * Writes out all pending buffered data over the open connection.
097     *
098     * @throws IOException in case of an I/O error
099     */
100    void flush() throws IOException;
101
102}