How to convert an HTML content to PDF without losing the formatting using Java?

Question

I have some HTML content (including formatting tags such as strong, images etc).In my Java code, I want to convert this HTML content into a PDF document without losing the HTML formatting.

Is there anyway to do it in Java (using iText or any other library)?

Answer 1

I used ITextRenderer from the Flying Saucer project.

Here is a short, self-contained, working example. In my case I wanted to later stream the bytes into an email attachment.

So, in the example I write it to a file purely for the sake of demonstration for this question. This is Java 8.

import com.lowagie.text.DocumentException;
import org.apache.commons.io.FileUtils;
import org.xhtmlrenderer.pdf.ITextRenderer;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;

public class So4712641 {

  public static void main(String... args) throws DocumentException, IOException {
    FileUtils.writeByteArrayToFile(new File("So4712641.pdf"), toPdf("<b>You gotta walk and don't look back</b>"));
  }

  /**
   * Generate a PDF document
   * @param html HTML as a string
   * @return bytes of PDF document
   */
  private static byte[] toPdf(String html) throws DocumentException, IOException {
    final ITextRenderer renderer = new ITextRenderer();
    renderer.setDocumentFromString(html);
    renderer.layout();
    try (ByteArrayOutputStream fos = new ByteArrayOutputStream(html.length())) {
      renderer.createPDF(fos);
      return fos.toByteArray();
    }
  }
}

This gives me

For completeness, here are relevant pieces for my Maven pom.xml

<dependencies>
    <dependency>
        <groupId>org.xhtmlrenderer</groupId>
        <artifactId>flying-saucer-pdf</artifactId>
        <version>9.0.8</version>
    </dependency>
    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>2.4</version>
    </dependency>
</dependencies>