javaperformancepdfxhtmlflying-saucer

Is there any way improve the performance of FlyingSaucer?

I've followed this article to use FlyingSaucer to convert XHTML to PDF and it's brilliant but has one major downfall... it's ridiculously slow!

I'm finding that it takes between 1 and 2 minutes to render a PDF from an XHTML, regardless of how simple that page is.

Basic code:

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.xhtmlrenderer.pdf.ITextRenderer;
import com.lowagie.text.DocumentException;

public class FirstDoc {

    public static void main(String[] args) throws IOException, DocumentException {

        String inputFile = "firstdoc.xhtml";
        String url = new File(inputFile).toURI().toURL().toString();
        String outputFile = "firstdoc.pdf";
        OutputStream os = new FileOutputStream(outputFile);

        ITextRenderer renderer = new ITextRenderer();
        renderer.setDocument(url);
        renderer.layout();
        renderer.createPDF(os);

        os.close();
    }
}

Sample XHTML:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>My First Document</title>
        <style type="text/css"> b { color: green; } </style>
    </head>
    <body>
        <p>
            <b>Greetings Earthlings!</b>
            We've come for your Java.
        </p>
    </body>
</html>

Does anyone know how to improve the performance of FlyingSaucer?

Failing that, is anyone able to recommend an alternative Java library which is effective at rendering a PDF from a URL to an (X)HTML document with external CSS and images generated from URLs?

Solution

  • Let me start by saying that I used your sample code and sample xhtml, and it "Ran in 2675ms".

    I downloaded flyingsaucer R8. And put three of the jars into my classpath.

    core-renderer.jar, iText-2.0.8.jar, xml-apis-xerces-2.9.1.jar

    I measured the run time by modifying your code with instrumentation...

    import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.xhtmlrenderer.pdf.ITextRenderer;
import com.lowagie.text.DocumentException;

public class FirstDoc {

    public static void main(String[] args) throws IOException, DocumentException {
        long start = System.currentTimeMillis();
        String inputFile = "firstdoc.xhtml";
        String url = new File(inputFile).toURI().toURL().toString();
        String outputFile = "firstdoc.pdf";
        OutputStream os = new FileOutputStream(outputFile);

        ITextRenderer renderer = new ITextRenderer();
        renderer.setDocument(url);
        renderer.layout();
        renderer.createPDF(os);

        os.close();
        long end = System.currentTimeMillis();
        System.out.println("Ran in " + (end-start) + "ms");
    }
}

    Now this library isn't exactly speedy, but it doesn't seem to be taking 1-2 minutes either. So now we need to figure out why it's running so slowly for you. Could you please let us know which JDK your using and on what platform? Also which version of flyingsaucer are you using?