JDBC is a standard API that is documented on the Oracle website. See the JDBC and the JDBC documentation content, noting the API limitations of the driver in Zen JDBC Driver Limitations.
Other useful sites for JDBC programming include Tomcat information at jakarta.apache.org and Apache information at www.apache.org.
For conceptual information on programming with the JDBC driver, see the following topics:
The Zen SDK includes JDBC samples in the samples directory under your Zen SDK installation directory. If you installed to the default location, it is file_path\Zen\sdk\samples\jdbc.