Set<String> (final VirtualFile vFile, final @Nullable VirtualFile contextVFile, final PsiManager psiManager, final String url) { return ReadAction.compute(() -> { PsiFile file = psiManager.findFile(vFile); if (file instanceof XmlFile) { PsiFile contextFile = contextVFile != null ? psiManager.findFile(contextVFile) : null; return extractEmbeddedFileReferences((XmlFile)file, contextFile instanceof XmlFile ? (XmlFile)contextFile : null, url); } return Collections.emptySet(); }); }