The JFace viewer framework is an independent module for JFace which needs some knowledge of SWT. The abstract base classes for viewers comprise the framework. The base class is the Viewer which is an extension of a structured viewer. The Viewer acts as a widget container. It is the responsibility for the content provider to respond to the various modifications to the model by informing the viewer, what to change (using add () and remove () methods).

Each viewer registers with the label provider for identifying / notifying the changes that would affect the viewers display.