If the JDK version 1.6 is used, the GlassFish Server supports JDBC 4.0 if the JDBC driver is JDBC 4.0 compliant. Using the Connection.unwrap() method on a vendor-provided interface returns an object or a wrapper object implementing the vendor-provided interface, which the application can make use of to do vendor-specific database operations. Use the Connection.isWrapperFor() method on a vendor-provided interface to check whether the connection can provide an implementation of the vendor-provided interface. Check the JDBC driver vendor's documentation for information on these interfaces.