dnovelty / pdfium-java

Java bindings to PDFium, Google's PDF manipulation and rendering library

PDFium Java

I exposed a couple methods from the PDFium library that can be called using this package. You do not need to have the shared object downloaded somewhere! It is bundled in this jar.

I have heard of automated ways of doing this like JNAerator, but I was running into a wall trying to get it to work, so I did a couple methods manually

Using

Currently, I have only bundled the linux x86_64 binary, so if you want to use it on another platform, let me know. It is as simple as adding a binary to an aptly named folder.

I hope to deploy this to maven central in the future. I may have done that by the time you are reading this. If so, download it using maven like so

<dependency>
    <groupId>io.github.abacef</groupId>
    <artifactId>pdfium</artifactId>
    <version>0.0.1</version>
</dependency>

or however you Gradle people do it. I am pretty sure you got used to translating by now.

import io.github.abacef.pdfium.fpdf_view.FPDF_LIBRARY_CONFIG;
import com.sun.jna.Memory;
import com.sun.jna.Native;
import com.sun.jna.Pointer;

public class Main{
    public static void main(String[] args) {
        final Pdfium pdfium = Pdfium.newInstance();

        final FPDF_LIBRARY_CONFIG config = new FPDF_LIBRARY_CONFIG();
        config.version = 2;
        config.m_pUserFontPaths = Pointer.NULL;
        config.m_pIsolate = Pointer.NULL;
        config.m_v8EmbedderSlot = 0;
        config.m_pPlatform = Pointer.NULL;
        pdfium.FPDF_InitLibraryWithConfig(config);

        final byte[] bytes = Files.readAllBytes(Paths.get("path/to/a/pdf.pdf"));

        final Memory pdfBytesMemory = new Memory((long) bytes.length * Native.getNativeSize(Byte.TYPE));
        IntStream.range(0, bytes.length).forEach(i ->
                pdfBytesMemory.setByte((long) i * Native.getNativeSize(Byte.TYPE), bytes[i]));
        
        // Implement some logic, for example rendering a PDF like https://github.com/mara004/pypdfium-reboot
        // Also, use Java BufferedImage to convert the bitmap to an image: 
        // https://github.com/Pacman29/Pdfium.Java/blob/master/src/main/java/pdfium/PDFBitmap.java#L49
    }
}

PDFium version

Pre-built binaries are taken from the releases of bblanchon's builds I am not sure which version is currently built with 0.0.1 of this package, but it is around 4619

Contributions

Feel free to submit pull requests to this repo, especially if you want to add public methods, since I only added the ones that I need to render a PDF the way I am doing it

Why did I create this package

I wanted to be able to render PDFs in Java and I realized that no one had published PDFium java bindings on maven central. There is obviously Pdfium.Java which I took some inspiration from, but it is not useable on the public repositories.