public TokenSource getTokenSource() {
        if (language == LanguageType.SCHEMA) {
            return originalSchemaNode.getTokenSource();
        }

        return null;
    }
SchemaNode represents a node in the AST of a file the language server parses.
The node exposes a general interface to handle different AST from different parsers.
integration/schema-language-server/language-server/src/main/java/ai/vespa/schemals/tree/SchemaNode.java