Can't set RTL direction for Hebrew letters while converting from *.xhtml to *.pdf by using iText library

问题

I'm trying to convert *.xhtml with Hebrew characters (UTF-8) to PDF by using iText library but I getting all letter in reverse order. As far I understand from this question I can set RTL only for ColumnText and PdfCell objects:

Arabic (and Hebrew) can only be rendered correctly in the context of ColumnText and PdfPCell.

So I doubt is it possible to convert whole *.xhtml page to PDF?

This is an *.xhtml file which I try to import:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head>
  <title>Title of document</title>
</head>

<body style="font-size:12.0pt; font-family:Arial">
  שלום עולם
</body>

</html>

And this is Java code which I use:

public static void convert() throws Exception{
            Document document = new Document();
            PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream("import.pdf"));
            writer.setRunDirection(PdfWriter.RUN_DIRECTION_RTL);
            document.open();

            String str = null;
            BufferedReader in = new BufferedReader(new InputStreamReader(new FileInputStream("import.xhtml"), "UTF8"));
            StringBuilder sb = new StringBuilder();

            while ((str = in.readLine()) != null) {
               System.out.println(str);
                sb.append(str);
            }
            in.close();


            XMLWorkerHelper worker = XMLWorkerHelper.getInstance();

            InputStream is = new ByteArrayInputStream(sb.toString().getBytes(StandardCharsets.UTF_8));
            worker.parseXHtml(writer, document, is, Charset.forName("UTF-8"));

            document.close();
        }
    }

This is what I get until now:

Thank you for any help.

回答1:

Please take a look at the ParseHtml10 example. In this example, we have take the file hebrew.html:

<html>

<head>
  <title>Hebrew text</title>
</head>

<body style="font-size:12.0pt; font-family:Arial">
<div dir="rtl" style="font-family: Noto Sans Hebrew">שלום עולם</div>
</body>

</html>

And we convert it to PDF using this code:

public void createPdf(String file) throws IOException, DocumentException {
    // step 1
    Document document = new Document();
    // step 2
    PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(file));
    // step 3
    document.open();
    // step 4
    // Styles
    CSSResolver cssResolver = new StyleAttrCSSResolver();
    XMLWorkerFontProvider fontProvider = new XMLWorkerFontProvider(XMLWorkerFontProvider.DONTLOOKFORFONTS);
    fontProvider.register("resources/fonts/NotoSansHebrew-Regular.ttf");
    CssAppliers cssAppliers = new CssAppliersImpl(fontProvider);
    HtmlPipelineContext htmlContext = new HtmlPipelineContext(cssAppliers);
    htmlContext.setTagFactory(Tags.getHtmlTagProcessorFactory());

    // Pipelines
    PdfWriterPipeline pdf = new PdfWriterPipeline(document, writer);
    HtmlPipeline html = new HtmlPipeline(htmlContext, pdf);
    CssResolverPipeline css = new CssResolverPipeline(cssResolver, html);

    // XML Worker
    XMLWorker worker = new XMLWorker(css, true);
    XMLParser p = new XMLParser(worker);
    p.parse(new FileInputStream(HTML), Charset.forName("UTF-8"));;
    // step 5
    document.close();
}

The result looks like hebrew.pdf:

What are the hurdles you need to take?

You need to wrap your text in an element such as a <div> or a <td>.
You need to add the attribute dir="rtl" to define the direction.
You need to make sure that you're using a font that knows how to display Hebrew. I used a NOTO font for Hebrew. This is one of the fonts distributed by Google in their program to provide fonts for every possible language.

I can't read Hebrew, but I hope the resulting PDF is correct and that this solves your problem.

Important: this solution requires at least iText and XML Worker 5.5.5, because support for the dir attribute was introduced in 5.5.4 and improved in 5.5.5.

来源：https://stackoverflow.com/questions/30847907/cant-set-rtl-direction-for-hebrew-letters-while-converting-from-xhtml-to-pd

标签

java

itext

right-to-left

hebrew

xmlworker