    001// Licensed under the Apache License, Version 2.0 (the "License");
    002// you may not use this file except in compliance with the License.
    003// You may obtain a copy of the License at
    004//
    005// http://www.apache.org/licenses/LICENSE-2.0
    006//
    007// Unless required by applicable law or agreed to in writing, software
    008// distributed under the License is distributed on an "AS IS" BASIS,
    009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    010// See the License for the specific language governing permissions and
    011// limitations under the License.
    012
    013package org.apache.tapestry5.http.services;
    014
    015import org.apache.tapestry5.http.ContentType;
    016
    017/**
    018 * Used to determine if the client supports GZip compression of the response.
    019 *
    020 * @see CompressionAnalyzer
    021 * @see org.apache.tapestry5.http.TapestryHttpSymbolConstants#GZIP_COMPRESSION_ENABLED
    022 * @since 5.1.0.0
    023 */
    024public interface ResponseCompressionAnalyzer
    025{
    026    /**
    027     * Checks the Accept-Encoding request header for a "gzip" token. Ensures that the protocol is not "HTTP/1.0", which
    028     * does not correctly support GZip encoding (in older Internet Explorer browsers).
    029     *
    030     * @return true if gzip is supported by client
    031     */
    032    boolean isGZipSupported();
    033
    034    /**
    035     * Uses {@link CompressionAnalyzer} to determine if the content is compressable, but only if the request
    036     * indicates the client supports compression.
    037     *
    038     * @param contentType
    039     * @return true if the content can be compressed for the current request
    040     * @since 5.4
    041     */
    042    boolean isGZipEnabled(ContentType contentType);
    043}