    001    // Copyright 2007, 2008, 2009, 2010, 2011 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
    015    package org.apache.tapestry5.internal.services;
    016
    017    import org.apache.tapestry5.ContentType;
    018    import org.apache.tapestry5.MarkupWriter;
    019    import org.apache.tapestry5.SymbolConstants;
    020    import org.apache.tapestry5.internal.InternalConstants;
    021    import org.apache.tapestry5.ioc.annotations.Inject;
    022    import org.apache.tapestry5.ioc.annotations.Symbol;
    023    import org.apache.tapestry5.json.JSONObject;
    024    import org.apache.tapestry5.services.*;
    025
    026    import java.io.IOException;
    027    import java.io.PrintWriter;
    028
    029    public class AjaxPartialResponseRendererImpl implements AjaxPartialResponseRenderer
    030    {
    031        private final MarkupWriterFactory factory;
    032
    033        private final Request request;
    034
    035        private final Response response;
    036
    037        private final PartialMarkupRenderer partialMarkupRenderer;
    038
    039        private final String outputEncoding;
    040
    041        private final boolean compactJSON;
    042
    043        private final Environment environment;
    044
    045        public AjaxPartialResponseRendererImpl(MarkupWriterFactory factory,
    046
    047                                               Request request,
    048
    049                                               Response response,
    050
    051                                               PartialMarkupRenderer partialMarkupRenderer,
    052
    053                                               @Inject
    054                                               @Symbol(SymbolConstants.CHARSET)
    055                                               String outputEncoding,
    056
    057                                               @Symbol(SymbolConstants.COMPACT_JSON)
    058                                               boolean compactJSON, Environment environment)
    059        {
    060            this.factory = factory;
    061            this.request = request;
    062            this.response = response;
    063            this.partialMarkupRenderer = partialMarkupRenderer;
    064            this.outputEncoding = outputEncoding;
    065            this.compactJSON = compactJSON;
    066            this.environment = environment;
    067        }
    068
    069        public void renderPartialPageMarkup() throws IOException
    070        {
    071            environment.cloak();
    072
    073            try
    074            {
    075                // This is a complex area as we are trying to keep public and private services properly
    076                // separated, and trying to keep stateless and stateful (i.e., perthread scope) services
    077                // separated. So we inform the stateful queue service what it needs to do here ...
    078
    079                ContentType pageContentType = (ContentType) request.getAttribute(InternalConstants.CONTENT_TYPE_ATTRIBUTE_NAME);
    080
    081                ContentType contentType = new ContentType(InternalConstants.JSON_MIME_TYPE, outputEncoding);
    082
    083                MarkupWriter writer = factory.newPartialMarkupWriter(pageContentType);
    084
    085                JSONObject reply = new JSONObject();
    086
    087                // ... and here, the pipeline eventually reaches the PRQ to let it render the root render command.
    088
    089                partialMarkupRenderer.renderMarkup(writer, reply);
    090
    091                PrintWriter pw = response.getPrintWriter(contentType.toString());
    092
    093                reply.print(pw, compactJSON);
    094
    095                pw.close();
    096            } finally
    097            {
    098                environment.decloak();
    099            }
    100        }
    101    }