Hello,
I have created a file named Aptfile with the package name of the JDK I want to install (openjdk-21-jdk-headless). But the “java” command-line is not in the PATH environment variable. I found it under “/layers/digitalocean_apt/apt/usr/lib/jvm/java-21-openjdk-amd64/bin”. But when I run my java JAR file, I always get the following error, whatever I do :
error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.InternalError: Error loading java.security file
Why don’t Aptfile never fully installs real Debian packages? I tried to install “language-pack-fr” too but the language is never built and activated.
Is Aptfile supposed to install packages from Debian or what ? What is the purpose of Aptfile ? Why packages get installed into “/layers” ??? What can I do to correctly install additional Linux packages ???
Thank you,
Claude Petit Senior Developer
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Hey Claude!
The Aptfile does install Debian packages, but App Platform uses buildpacks under the hood (just like Heroku), and the packages from your Aptfile get installed into a special layer (that’s the /layers/... path you’re seeing).
Java is there, but you might have to manually add it to your PATH in your start command or your app config. Something like:
export PATH="/layers/digitalocean_apt/apt/usr/lib/jvm/java-21-openjdk-amd64/bin:$PATH"
java -jar your-app.jar
As for language-pack-fr, same issue, those kinds of system-level changes (like locales) might not work as expected in this environment, because it’s not a full VM. App Platform runs in containers with strict buildpack layers, so some things just don’t fully apply.
You could use a Dockerfile to deploy your app so you could install any of the packages that you need:
https://docs.digitalocean.com/products/app-platform/reference/dockerfile/
Alternatively you could use a Droplet where you have full root access:
Hope that this helps.
- Bobby
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