Verify Java release signature MacOSX
wget https://download.java.net/java/GA/jdk15.0.2/0d1cfde4252546c6931946de8db48ee2/7/GPL/openjdk-15.0.2_osx-x64_bin.tar.gz
wget https://download.java.net/java/GA/jdk15.0.2/0d1cfde4252546c6931946de8db48ee2/7/GPL/openjdk-15.0.2_osx-x64_bin.tar.gz.sha256
openssl dgst -sha256 openjdk-15.0.2_osx-x64_bin.tar.gz
SHA256(openjdk-15.0.2_osx-x64_bin.tar.gz)= 578b17748f5a7d111474bc4c9b5a8a06b4a4aa1ba4a4bc3fef014e079ece7c74
cat openjdk-15.0.2_osx-x64_bin.tar.gz.sha256
578b17748f5a7d111474bc4c9b5a8a06b4a4aa1ba4a4bc3fef014e079ece7c74
for install steps see https://knasmueller.net/how-to-install-java-openjdk-15-on-macos-big-sur