GlassFish 5 and MySQL Connector

Solution 1:

What worked for me:

Datasource Classname: com.mysql.cj.jdbc.MysqlConnectionPoolDataSource 

Two new "Additional Properties" to the JDBC Connection Pool :

useSSL = false 
serverTimezone = UTC (this is not even true in my case, I am UTC+2) 

Here one remark : when I installed MySQL instance, I expressly set it NOT to use SSL for the passwords from the option in the installer on the regarding page.

other "Additonal Properties " are :

password = myPass 
databaseName = sakila 
serverName = localhost 
user = root 
networkProtocol = jdbc 
portNumber = 3306 

.. and it succeeded