Downgrade to java 9

I am trying to build the tinyB.jar for java Blue-Tooth abilities. The build script is not compatible with java 10. How can I downgrade from java 10 to java 9. I am running the latest version of Debian.

Are you building on the Dragonboard ?

That works on my side:

apt-get install pkg-config
apt-get install cmake
apt-get install libglib2.0-dev
apt-get install openjdk-10-jdk

git clone https://github.com/intel-iot-devkit/tinyb.git
cd tinyb
mkdir build
cd build
cmake .. -DBUILDJAVA=ON
make
make install

If I follow those instructions, I get an error running :
cmake … -DBUILDJAVA=ON

CMake Error at java/CMakeLists.txt:16 (message):
Cannot locate javah executable.

Hmm rigth, I have previously installed openjdk8

apt-get install openjdk-8-jdk

check:

update-alternatives --get-selections | grep javah
javah                          auto     /usr/lib/jvm/java-8-openjdk-arm64/bin/javah