ClassPath Preferences panel allows users to add or remove locations of the external class libraries (JAR, ZIP, or class directories). These external libraries will be used by CayenneModeler to load JDBC drivers, custom DB adapters, or any other Java resources that are not a part of the Modeler distribution itself.

Modeler ClassNotFound Errors
If you encounter any CLASSPATH-related errors during DB reverse engineering, DataSource configuration, etc., in most cases you simply need to go to Preferences ClassPath panel and add an entry pointing to a missing external library.