Keerati

I ended up working this out with the help of this post - specifically, if you add the following to /boot/armbianEnv.txt, you can force the video mode.
 
Some examples:
 
640x480
extraargs=drm_kms_helper.edid_firmware=HDMI-A-1:edid/640x480.bin video=HDMI-A-1:640x480-24@60  
1080p
extraargs=drm_kms_helper.edid_firmware=HDMI-A-1:edid/1920x1080.bin video=HDMI-A-1:1920x1080@60  
I didn't have to install any extra packages or anything using Armbian Debian Stretch / 4.14.78-sunxi, it just worked out of the box (edid files already installed/etc).

@KeeratiI replied to your post on github. The input file is for MMIO GPIO mappings and not used by LedBlink. Use --help argument on any demo or tool for list of arguments such as gpio chip, pin, etc.

Java UIO provides high performance Java interfaces for Linux Userspace IO. Java UIO was built from the ground up to use modern kernel APIs, libraries and code generation techniques to provide a best of breed cross platform approach. It does not make sense to recreate the wheel like so many other IO libraries. JDK 17 LTS is supported out of the box.
 
I've been committing code to U8g2 that utilizes the same userspace code at the C level and dramatically improved the performance of HW/SW SPI and I2C in the arm-linux port. I also made the arm-linux port thread safe and multi display capable (you can use this in C as well obviously). It made sense to add modularization to the Java Periphery IO library since I can take advantage of the same code generation techniques. I will continue to wrap optimized C libraries moving forward in the same modular fashion.
 
So now you can develop against IO and small displays with one code base in Java.