org.zlogic.voidreader.handler.impl.AbstractPdfHandler.java Source code

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Here is the source code for org.zlogic.voidreader.handler.impl.AbstractPdfHandler.java

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/*
 * Void Reader project.
 * Licensed under Apache 2.0 License: http://www.apache.org/licenses/LICENSE-2.0
 * Author: Dmitry Zolotukhin <zlogic@gmail.com>
 */
package org.zlogic.voidreader.handler.impl;

import com.itextpdf.text.DocumentException;
import com.itextpdf.text.pdf.BaseFont;
import java.io.IOException;
import java.net.URL;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Entities;
import org.jsoup.safety.Cleaner;
import org.jsoup.safety.Whitelist;
import org.xhtmlrenderer.pdf.ITextFontResolver;
import org.xhtmlrenderer.pdf.ITextRenderer;
import org.xhtmlrenderer.render.FSFont;
import org.zlogic.voidreader.fonts.FontsList;

/**
 * Abstract class with PDF generation functions. Can be inherited by other
 * handlers to provide PDF generations features.
 *
 * @author Dmitry Zolotukhin <a
 * href="mailto:zlogic@gmail.com">zlogic@gmail.com</a>
 */
public abstract class AbstractPdfHandler {

    /**
     * The list of fonts included with this application
     */
    private FontsList fontsList = new FontsList();

    /**
     * Renders an XHTML page to PDF
     *
     * @param html the page XHTML contents
     * @param baseUrl the page base URL
     * @return an ITextRenderer which can be used to produce the final PDF
     * document
     * @throws IOException when fonts cannot be located
     * @throws DocumentException when an error prevents the PDF document from
     * being generated
     */
    protected ITextRenderer renderPdf(String html, String baseUrl) throws IOException, DocumentException {
        ITextRenderer renderer = new ITextRenderer();

        //Replace with custom font resolver
        ITextFontResolver fontResolver = new ITextFontResolver(renderer.getSharedContext()) {
            @Override
            public org.xhtmlrenderer.render.FSFont resolveFont(
                    org.xhtmlrenderer.layout.SharedContext renderingContext,
                    org.xhtmlrenderer.css.value.FontSpecification spec) {
                spec.families = new String[] { "Open Sans" }; //NOI18N
                FSFont font = super.resolveFont(renderingContext, spec);
                return font;
            }
        };
        renderer.getSharedContext().setFontResolver(fontResolver);

        //Override fonts
        for (URL url : fontsList.getFontUrls())
            if (url.toExternalForm().endsWith(".ttf")) //NOI18N
                fontResolver.addFont(url.toExternalForm(), BaseFont.IDENTITY_H, true);

        renderer.setDocumentFromString(html, baseUrl);
        renderer.layout();
        return renderer;
    }

    /**
     * Downloads a feed item's URL with Flying Saucer, converts to XHTML and
     * performs a tag cleanup, and finally renders the result to PDF.
     *
     * @param url the URL to download
     * @return an ITextRenderer which can be used to produce the final PDF
     * document
     * @throws IOException when fonts cannot be located
     * @throws DocumentException when an error prevents the PDF document from
     * being generated
     */
    protected ITextRenderer downloadRenderPdf(String url) throws IOException, DocumentException {
        Document htmlDocument = Jsoup.connect(url).followRedirects(true).timeout(60000).get();//TODO: make timeout configurable
        Cleaner cleaner = new Cleaner(Whitelist.relaxed().preserveRelativeLinks(false).addTags("span") //NOI18N
                .addAttributes("span", "id", "style")); //NOI18N
        Document htmlDocumentClean = cleaner.clean(htmlDocument);
        htmlDocumentClean.setBaseUri(url);
        htmlDocumentClean.outputSettings().prettyPrint(false);
        htmlDocumentClean.outputSettings().escapeMode(Entities.EscapeMode.xhtml);
        /*
         for (Element element : htmlDocument.head().getAllElements()) {
         switch (element.tagName().toLowerCase()) {
         case "style":
         Element styleElement = htmlDocumentClean.head().appendElement(element.tagName());
         styleElement.appendText(element.text());
         for (Node dataNode : element.dataNodes())
         styleElement.appendChild(dataNode);
         for (Attribute attribute : element.attributes())
         if (attribute.getKey().toLowerCase().equals("id") || attribute.getKey().toLowerCase().equals("type"))
         styleElement.attr(attribute.getKey(), attribute.getValue());
         break;
         case "link":
         Element linkElement = htmlDocumentClean.head().appendElement(element.tagName());
         linkElement.appendText(element.text());
         for (Attribute attribute : element.attributes())
         if (attribute.getKey().toLowerCase().equals("rel") || attribute.getKey().toLowerCase().equals("href") || attribute.getKey().toLowerCase().equals("type"))
         linkElement.attr(attribute.getKey(), attribute.getValue());
         for (Node dataNode : element.dataNodes())
         linkElement.appendChild(dataNode);
         break;
         }
         }
         */
        return renderPdf(htmlDocumentClean.html(), url);
    }
}