The AST is already cached so the parsing effort is skipped for both param and param-less queries when are executed repeatedly.

A further minor perf improvement can be achieved by caching also the output of the AST-to-Lucene transformation phase. This can only be done for queries without parameters (because the params would become bound to the Lucene query objects - which are immutable, btw). The Lucene transformation is a low complexity/effort process but even so it is better to skip it entirely when possible.