We are considering the move to HikariCP (we are currently using the Tomcat pool) but there is something bothering us in the way we have to configure it.
Context: our core framework supports a lot of databases: PostgreSQL (which is our database of choice - I'm an ancient PostgreSQL contributor), MySQL, Oracle, SQL Server, H2... They are all configured in a generic way using a JDBC URL.
The Driver API, which is the API chosen by the connection pool we are using, allows to configure the Connection with a JDBC URL, which is comfortable as we can configure every database the same way.
HikariCP is based on the DataSource API which isn't really made to create a connection: it
doesn't expose a stable interface for this and it's
definitely a pain to have something generic for all the databases: the PostgreSQL DataSource implementation requires the database name, the host and the port, the SQL Server one wants a capitalized URL property whereas MySQL wants a lowercase url property...
Providing a generic way to configure the connection to a database with this API is clearly not as simple as with the Driver interface.