private synchronized SwingWorkerImpl getWorker() {
		if (worker == null) {
			worker = new SwingWorkerImpl();
			worker.execute();
		}
		return worker;

	}
A method for clients to use as a callback for completion.  This method will be called in
the Swing thread, after the value has been set.
Ghidra/Framework/Docking/src/main/java/ghidra/util/task/CachingSwingWorker.java