That's the UI editor of the already since ~3 years dead and abandoned Woodstock library . That library became an epic failure due to an bug which revealed when Firefox 3 was released. It turned out that the library generates non-standards compliant Javascript which broke in the newer and more standards-compliant browsers. It was a hard smack in Woodstock's face.
Since then, users were recommended to migrate to ICEfaces 1.x. There's an auto-migration tool for ICEfaces. ICEfaces in turn has a visual editor plugin for Netbeans. The visual editor has been removed from Netbeans since version 6.8. See also wiki.netbeans.org/VisualWebSupport:
VisualWebSupport
Where can I find the Visual Web Pack with Visual Editor support for web page design?
Starting from NetBeans 6.8, the Visual Web module is no longer available. No further development is planned.
Another fact is, using visual editors with code generators is strongly discouraged in the professional development world. They were often used by starters only and it produces unmaintainable and unreuseable code to a high degree. On the other hand, it makes debugging and nailing down code-level problems much harder for starters, because they don't understand any line of the generated code. It also unnecessarily gave JSF in general a negative imago.
If you're new to coding, don't drag'n'drop code, but just write code.
If you like to develop JSF on Netbeans, I recommend walking through the latest tutorials at Netbeans.org instead (using a normal code editor!). You can find them all here. With regard to learning JSF in general, start at our JSF wiki page for a Hello World and useful links.
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