$ java -cp classes RefCheck      (25.0.5+8-LTS)
== RefHkdf (HmacSHA256 only) on RFC 5869 A.1 basic
PASS  PRK
PASS  OKM
== RefHkdf (HmacSHA256 only) on RFC 5869 A.2 long inputs
PASS  PRK
PASS  OKM
== RefHkdf (HmacSHA256 only) on RFC 5869 A.3 empty salt and info
PASS  PRK
PASS  OKM
ALL CHECKS PASSED
exit=0

$ java -cp classes Interop interop/cases.tsv      (25.0.5+8-LTS)
== interop/cases.tsv: 300 cases {SHA256=100, SHA384=100, SHA512=100}, longest output 16320 bytes
PASS  JDK KDF API matches Python cryptography on 300 of 300
PASS  hand-written RefHkdf matches Python cryptography on 300 of 300
ALL CHECKS PASSED
exit=0