If you check inside the WAR file for the booking application, you'll find seam-ui.jar in the WEB-INF/lib directory. This package contains a number of JSF custom controls that integrate with Seam. The booking application uses the <s:link> control for navigation from the search screen to the hotel page:

<s:link value="View Hotel" action="#{hotelBooking.selectHotel}"/>

The use of <s:link> here allows us to attach an action listener to a HTML link without breaking the browser's "open in new window" feature. The standard JSF <h:commandLink> does not work with "open in new window". We'll see later that <s:link> also offers a number of other useful features, including conversation propagation rules.

The booking application uses some other Seam and Ajax4JSF controls, especially on the /book.xhtml page. We won't get into the details of those controls here, but if you want to understand this code, please refer to the chapter covering Seam's functionality for JSF form validation.