jdbc with no default db have one extra null byte cause handshake fail (no replies)

we are using jdbc to connect a mysql-proxy,found that jdbc is different from mysql protocal when dealing no default db connection


here is the mysql protocal,Protocol::HandshakeResponse41

if CLIENT_CONNECT_WITH_DB is set,then have a string[NULL],if not set,then have nothing


however,in jdbc source code,we found this: in function

proceedHandshakeWithPluggableAuthentication

if (this.useConnectWithDb) {
last_sent.writeString(database, enc, this.connection);
} else {
/* For empty database */
last_sent.writeByte((byte) 0);
}

if CLIENT_CONNECT_WITH_DB is not set,jdbc write a extra null byte. we use tcpdump verify this.


is this a bug?