https://support.adeptia.com/hc/en-us/articles/207878953-How-to-create-a-KeyStore-with-certificate-chain
cat myserver.srt intermediate.crt root.crt > cert-chain.txt
openssl pkcs12 -export -inkey server.key -in cert-chain.txt -out cert-chain.pkcs12
keytool -importkeystore -srckeystore cert-chain.pkcs12 -srcstoretype PKCS12 -destkeystore SSLKeystore.jks