Eclipse Platform(tm) consists of small modules (plugins) that are integrated in run-time to produce the final application. This integration is performed through the use of extension points, examples of which include menus, toolbars, views, editors, etc. This architecture is very flexible and yields great results. However this flexibility comes at expense of being able to say where UI elements come from and how they're implemented.
UI Inspector for Eclipse was created to address these difficulties. It is a plugin that contains a single view that allows you to see the properties of the selected objects and their context. You can simply point and click on any object and it will show you information about selected menus, perspectives, contributing plugins, SWT controls and associated data and actions. UI Inspector plugin can be installed in your Eclipse IDE or easily included in a RCP application.