[graalvm-users] Creating maven artifacts for native libs

[Samuel Audet]

Hi,

In theory, Sulong can compile x265 to fully portable bytecode, and these 
files can be packaged into Maven artifacts like any other Java classes, 
but the performance that we would get from that may not be satisfactory. 
It would probably be around 10x slower than native binaries since Java 
bytecode isn't able to accommodate for native assembly instructions that 
are used heavily in encoders such as x265. Also, we may need 
dependencies on GraalVM, Truffle, and Sulong, so we wouldn't get a small 
independent package that could run on the JDK, but I'm not entirely sure 
about that. Those projects are still pretty experimental, so that's 
probably why I'm not finding a friendly way to try it out. :)

Because of these kinds of limitations, what everyone does, including 
very official projects from OpenJDK like JavaFX, is simply to package 
native libraries in JAR files and access them with JNI. It works fine 
for multiple platforms as well. For example, I'm making packages for 
FFmpeg (which include x265) available here:
https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_bytedeco_javacpp-2Dpresets_tree_master_ffmpeg&d=DwICaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=CUkXBxBNT_D5N6HMJ5T9Z6rmvNKYsqupcbk72K0lcoQ&m=-y3UTZ_tBKQeIv6IAXbDNph16osrPfuA9gB3qtME4Is&s=1EPblxJJw_xdDfm8sMo2cl4X53yQfK6dV_-YlIj5gis&e= 

There are binaries for Android (ARM, ARM64, x86, x86_64), Linux (ARM, 
ARM64, POWER, x86, x86_64), Mac (x86_64), and Windows (x86 and x86_64), 
all accessible from a single Maven artifact named "ffmpeg-platform", but 
we can create builds easily for more platforms. To get smaller JAR 
files, we can also limit the scope of the builds to small libraries such 
as only x265 itself.

Samuel

On 11/25/19 4:47 PM, Ramsey Gurley wrote:
> Hi all,
> 
> I'd like to compile a native lib with graal to be distributed as a maven
> artifact. I have a few questions.
> 
> Are native libraries platform specific if compiled with graalvm's llvm
> tools? Let's say I want to compile x265. Do I need one artifact per
> arch? Per os?
> 
> Once created, can the graal compiler used by OpenJDK make use of them?
> Or is a graalvm with llvm tools installed a requirement?
> 
> Basically, I want to fill a gap in Java, which is video codecs and a
> swing component to use them. I'm hoping graalvm is a good way to do this.
> 
> Thank you,
> 
> Ramsey
> 
>