When you are developing your project, JBoss Developer Studio constantly provides error checking. This greatly reduces your development time as it allows you to catch many of the errors during development.
Errors will be reported by JBoss Developer Studio's verification facility:
Other errors are also reported.
You can also work in the Source editor with the help of the Outline view. The Outline views show a tree structure of the JSF configuration file. Simply select any element in the Outline view, and it will jump to the same place in the Source editor, so you can navigate through the source code with Outline view.
If your diagram is large, within Outline view you can switch to a Diagram Navigator mode by selecting the middle icon at the top of the view window. It allows you to easily move around the diagram. Just move the blue area in any direction, and the diagram on the left will also move:
You can also edit the properties of the selected element in the Tree mode with the help of the Properties view as shown below: