org.glassmaker.eclipse/org.glassmaker.ui.editor/src/main/java/org/glassmaker/ui/editor/CardEditor.java
public void init(IEditorSite site, IEditorInput editorInput) throws PartInitException {
		if (!(editorInput instanceof IFileEditorInput))
			throw new PartInitException("Invalid Input: Must be IFileEditorInput");
		super.init(site, editorInput);
	}
public void init(IEditorSite site, IEditorInput editorInput) throws PartInitException {
		if (!(editorInput instanceof IFileEditorInput))
			throw new PartInitException("Invalid Input: Must be IFileEditorInput");
		super.init(site, editorInput);
	}
The <code>MultiPageEditorExample</code> implementation of this method
checks that the input is an instance of <code>IFileEditorInput</code>.