1) Clone the hpmtissera/tinycore-jdk11-tcz repository from Github
https://github.com/hpmtissera/tinycore-jdk11-tcz.git
 2) Download required OpenJDK11 tar.gz file from https://github.com/AdoptOpenJDK/openjdk11-upstream-binaries/releases and copy it inside tinycore-jdk11-tcz folder.
ex. OpenJDK11U-jdk_aarch64_linux_11.0.4_11.tar.gz
3) Run build.sh script
./build.sh
4) The script will generate a file named jdk11.tcz.