com.twinsoft.convertigo.engine.requesters.PdfServletRequester.java Source code

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Here is the source code for com.twinsoft.convertigo.engine.requesters.PdfServletRequester.java

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/*
 * Copyright (c) 2001-2011 Convertigo SA.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see<http://www.gnu.org/licenses/>.
 *
 * $URL$
 * $Author$
 * $Revision$
 * $Date$
 */

package com.twinsoft.convertigo.engine.requesters;

import java.io.File;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;

import javax.xml.transform.Result;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.stream.StreamSource;

import org.apache.fop.apps.FOUserAgent;
import org.apache.fop.apps.Fop;
import org.apache.fop.apps.FopFactory;
import org.apache.fop.apps.MimeConstants;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

import com.twinsoft.convertigo.engine.Engine;
import com.twinsoft.convertigo.engine.EngineException;
import com.twinsoft.convertigo.engine.EngineStatistics;

public class PdfServletRequester extends ServletRequester {

    private FopFactory fopFactory;

    public void preGetDocument() throws EngineException {
        super.preGetDocument();
        context.isXsltRequest = true;
    }

    public PdfServletRequester(FopFactory fopFactory) {
        this.fopFactory = fopFactory;
    }

    public String getName() {
        return "PdfServletRequester";
    }

    public void setStyleSheet(Document document) {
        // Nothing to do
    }

    protected Object performXSLT(Document document) throws Exception {
        String t1 = context.statistics.start(EngineStatistics.XSLT);

        try {
            Engine.logEngine.debug("XSL/FO process is beginning");

            Object result = null;

            Engine.logEngine.debug("Sheet absolute URL: " + context.absoluteSheetUrl);
            if (context.absoluteSheetUrl == null)
                throw new EngineException(
                        "You have required an XSL/FO process, but Convertigo has been unable to find a stylesheet for your request. Verify your project's settings.");

            // XSL/FO engine
            StreamSource streamSource = null;
            try {
                // Configure foUserAgent as desired
                FOUserAgent foUserAgent = fopFactory.newFOUserAgent();
                foUserAgent.setBaseURL(
                        new File(Engine.PROJECTS_PATH + "/" + context.projectName).toURI().toASCIIString());
                foUserAgent.setAuthor("Convertigo EMS");

                // Setup output
                org.apache.commons.io.output.ByteArrayOutputStream out = new org.apache.commons.io.output.ByteArrayOutputStream();

                // Construct fop with desired output format
                Fop fop = fopFactory.newFop(MimeConstants.MIME_PDF, foUserAgent, out);

                // Setup XSLT
                streamSource = new StreamSource(new File(context.absoluteSheetUrl).toURI().toASCIIString());
                TransformerFactory factory = TransformerFactory.newInstance();
                Transformer transformer = factory.newTransformer(streamSource);

                // Setup input for XSLT transformation
                Element element = document.getDocumentElement();
                DOMSource src = new DOMSource(element);

                // Resulting SAX events (the generated FO) must be piped through to FOP
                Result res = new SAXResult(fop.getDefaultHandler());

                // Start XSLT transformation and FOP processing
                transformer.transform(src, res);

                result = out.toByteArray();
            } finally {
                if (streamSource != null) {
                    InputStream inputStream = streamSource.getInputStream();
                    if (inputStream != null)
                        inputStream.close();
                }
            }

            Engine.logEngine.trace("XSLT result:\n" + result);

            return result;
        } finally {
            Engine.logEngine.debug("XSLT process has finished");
            context.statistics.stop(t1);
        }
    }

    protected Object addStatisticsAsData(Object result) {
        return result;
    }

    protected Object addStatisticsAsText(String stats, Object result) throws UnsupportedEncodingException {
        return result;
    }
}