001// Copyright 2009, 2012 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry5.http.internal.gzip; 016 017import java.io.IOException; 018 019import javax.servlet.http.HttpServletRequest; 020import javax.servlet.http.HttpServletResponse; 021 022import org.apache.tapestry5.http.TapestryHttpSymbolConstants; 023import org.apache.tapestry5.http.services.CompressionAnalyzer; 024import org.apache.tapestry5.http.services.HttpServletRequestFilter; 025import org.apache.tapestry5.http.services.HttpServletRequestHandler; 026import org.apache.tapestry5.http.services.ResponseCompressionAnalyzer; 027import org.apache.tapestry5.ioc.annotations.Symbol; 028 029/** 030 * Filter that adds GZIP compression to the response, if the client supports it. 031 */ 032public class GZipFilter implements HttpServletRequestFilter 033{ 034 private final int cutover; 035 036 private final ResponseCompressionAnalyzer responseAnalyzer; 037 038 private final CompressionAnalyzer compressionAnalyzer; 039 040 public GZipFilter( 041 @Symbol(TapestryHttpSymbolConstants.MIN_GZIP_SIZE) 042 int cutover, 043 044 ResponseCompressionAnalyzer responseAnalyzer, 045 046 CompressionAnalyzer compressionAnalyzer) 047 { 048 this.cutover = cutover; 049 this.responseAnalyzer = responseAnalyzer; 050 this.compressionAnalyzer = compressionAnalyzer; 051 } 052 053 public boolean service(HttpServletRequest request, HttpServletResponse response, HttpServletRequestHandler handler) 054 throws IOException 055 { 056 HttpServletResponse newResponse = responseAnalyzer.isGZipSupported() 057 ? new GZIPEnabledResponse(response, request, cutover, compressionAnalyzer) 058 : response; 059 060 return handler.service(request, newResponse); 061 } 062}