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 org.apache.http.util.CharArrayBuffer;
031
032/**
033 * An HTTP header which is already formatted.
034 * For example when headers are received, the original formatting
035 * can be preserved. This allows for the header to be sent without
036 * another formatting step.
037 *
038 * @since 4.0
039 */
040public interface FormattedHeader extends Header {
041
042    /**
043     * Obtains the buffer with the formatted header.
044     * The returned buffer MUST NOT be modified.
045     *
046     * @return  the formatted header, in a buffer that must not be modified
047     */
048    CharArrayBuffer getBuffer();
049
050    /**
051     * Obtains the start of the header value in the {@link #getBuffer buffer}.
052     * By accessing the value in the buffer, creation of a temporary string
053     * can be avoided.
054     *
055     * @return  index of the first character of the header value
056     *          in the buffer returned by {@link #getBuffer getBuffer}.
057     */
058    int getValuePos();
059
060}