Is it inevitable that SWT is a dependency in an Eclipse RCP application?

Question

Say, I have an application based on the e4 platform using pure JavaFX instead of SWT as a rendering technology, like this one. Does it still need some SWT libraries indirectly? After all, the Eclipse platform is based on SWT. Am I understanding it the right way? I can't see any direct dependencies from the Dependencies tab as following though.

Answer 1

The core of Eclipse 4 is not based on SWT. The UI toolkit used for Eclipse is defined by a set of renderers. Each renderer is responsible for showing a particular object from the application model (part stack, toolbar, and so on).

The standard renderers use SWT but e(fx)clipse changes this to a set using JavaFX.

A single renderer factory is used to create all these renderers. The renderer factory is defined by the rendererFactoryUri property of the org.eclipse.core.runtime.products extension point.

This only applies to the Eclipse core, lots of Eclipse plug-ins are coded using SWT directly and would have to be rewritten to use JavaFX.