Concurrency and mutual versioning context?

[hrstoyanov]

Looking at this example for mutual versioning context - how is the versionContext.currentVersion("rev-1"); work at all? It seems like different threads can set the current revision and. so you will never know what the current version is? Is EntityVersionContext.Mutable thread-safe?

EntityVersionContext.Mutable<String> versionContext = EntityVersionContext.Mutable();

versionContext.currentVersion("rev-1");

Person john = PersonCreator.New()
	.addLayer(versionContext)
	.firstName("John")
	.lastName("Doe")
	.create();

versionContext.currentVersion("rev-2");
PersonUpdater.setLastName(john, "Smith");