Do the underlying JPA JDBC connection can stream?

Question

We have a Java EE application using JPA. User can ask the app to generate some output (big charts, etc) based on results of a large query, so in that case we decided to use directly JDBC and looping over the resultset. We have implemented our code like this:

@Resource(mappedName = "jdbc/resource")   
private DataSource dataSource;    

Connection connection = dataSource.getConnection();

[...]

Connection conn = dataSource.getConnection();
stmt = conn.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(Integer.MIN_VALUE);

[...]

ResultSet rs = stmt.executeQuery(sql);
while (rs.hasNext()) {
    [....]
}

Anyway it always load all the results in memory, we have tried with different techniques (useCursorFetch true and fetch size = 10, etc) with no luck, we always fail to have a stream resultset.

The "jdbc/resource" is the same resource used by jpa entity manager (so it's working fine), the connection have no "weird" options, we are using glassfish 4.1 for our tests and we are using the connector/J version 5.1.26 and 5.1.32.

It there a way to have a working streaming resultset?