public TokenType getDirtyType() {
        if (language != LanguageType.SCHEMA) return null;
        ai.vespa.schemals.parser.Node.NodeType originalType = originalSchemaNode.getType();
        if (originalType instanceof TokenType)return (TokenType)originalType;
        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