This package defines the core application runtime classes and exception. The main class developers will use is the {@link org.apache.click.Page} class which provides application pages, the {@link org.apache.click.Context} class which provides page's their request context, and {@link org.apache.click.Control} interface which Page controls extend.

Other classes include the {@link org.apache.click.ClickServlet} which provides the Click runtime environment, and ClickApp which encapsulates the Click application configuration. This class has package private visibility and are not intended for general use. Of course as an open source project this class can be modified to suite individual needs.