@Override
    public CompletableFuture<List<? extends DocumentHighlight>> documentHighlight(DocumentHighlightParams params) {

        return CompletableFutures.computeAsync((cancelChecker) -> {
            return new ArrayList<DocumentHighlight>();
        });
    }
SchemaTextDocumentService handles incomming requests from the client.
integration/schema-language-server/language-server/src/main/java/ai/vespa/schemals/SchemaTextDocumentService.java