001// Copyright 2007, 2008, 2010 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.internal.services;
016
017import org.apache.tapestry5.ComponentResources;
018import org.apache.tapestry5.ContentType;
019import org.apache.tapestry5.MetaDataConstants;
020import org.apache.tapestry5.SymbolConstants;
021import org.apache.tapestry5.internal.structure.Page;
022import org.apache.tapestry5.ioc.annotations.Symbol;
023import org.apache.tapestry5.services.MetaDataLocator;
024
025public class PageContentTypeAnalyzerImpl implements PageContentTypeAnalyzer
026{
027    private final MetaDataLocator metaDataLocator;
028
029    private final String outputCharset;
030
031    public PageContentTypeAnalyzerImpl(MetaDataLocator metaDataLocator,
032
033    @Symbol(SymbolConstants.CHARSET)
034    String outputCharset)
035    {
036        this.metaDataLocator = metaDataLocator;
037        this.outputCharset = outputCharset;
038    }
039
040    public ContentType findContentType(Page page)
041    {
042        ComponentResources pageResources = page.getRootComponent().getComponentResources();
043
044        String contentTypeString = metaDataLocator.findMeta(MetaDataConstants.RESPONSE_CONTENT_TYPE, pageResources,
045                String.class);
046
047        // Draconian but necessary: overwrite the content type they selected with the application-wide output charset.
048
049        return new ContentType(contentTypeString, outputCharset);
050    }
051}