The ADF Faces tree component af:tree displays hierarchical data, such as organization charts or hierarchical directory structures. In data of these types, there may be a series of top-level nodes, and each element in the structure may expand to contain other elements. In the shopping example shown in the slide, each element, that is, each category, in the hierarchy may have any number of child elements (products). In addition, several parent elements may share the same child elements.
The af:tree component supports multiple root elements. It displays the data in a form that represents the structure, with each element indented to the appropriate level to indicate its level in the hierarchy, and connected to its parent. Users can expand and collapse portions of the hierarchy.