A DESCRIPTION OF THE PROBLEM :
The documentation contains: "before handshaking can can continue."
There is a "can" too much here.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
before handshaking can continue.
ACTUAL -
before handshaking can can continue.

URL OF FAULTY DOCUMENTATION :
http://download.java.net/java/jdk9/docs/api/javax/net/ssl/SSLEngineResult.HandshakeStatus.html#NEED_UNWRAP_AGAIN