About Question enthuware.ocpjp.ii.v11.2.1199 :

[liugengyu]

A JDBC driver implementation must provide implementation classes for which of the following interfaces?
I don't understand the question and the answer at all. What does it mean by JDBC driver implementation? Can soneone explain it for me?

Thanks a lot.

[admin]

The Java JDBC package is just a set of interfaces and helper classes. They don't really contain any code to actually connect to any database and fetch data/execute queries etc. Every database vendor (such as Oracle, MSSQL, MySQL etc.) provides the implementation classes for these interfaces, which do the real work of connecting to their database.

See this for details: https://www.marcobehler.com/guides/jdbc

[liugengyu]

Understood. Already added your comments into my note. Thanks!

[liugengyu]

The Java JDBC package is just a set of interfaces and helper classes. They don't really contain any code to actually connect to any database and fetch data/execute queries etc. Every database vendor (such as Oracle, MSSQL, MySQL etc.) provides the implementation classes for these interfaces, which do the real work of connecting to their database.

See this for details: https://www.marcobehler.com/guides/jdbc

Understood. Already added your comments into my note. Thanks!

[noeloo]

The most important benefit is that the application code does not need to have access to database connection details (i.e. userid, pwd, and dburl).

Doesn't it?
I'm going through Oracle tutorial (I know it's written for Java 8, but did it really change later?) at https://docs.oracle.com/javase/tutorial ... urces.html and from what I see, you still need to pass user and password when getting a connection.

[admin]

Yes, a DataSource is configured in the application contaciner. Application code simply looks the data source up using JNDI and call dataSource.getConnection(). No connection parameters are required because application code does not "create" a data source. The deployer creates (actually, "configures") datasource in the application container. While configuration, the deployer specifies the url, userid, password, and other connection parameters.