@Override
	public LocalManagedBufferFile open() throws IOException {
		synchronized (fileSystem) {
			if (isVersioned) {
				return versionedDb.openBufferFile(LATEST_VERSION, -1);
			}
			return privateDb.openBufferFile();
		}
	}
<code>LocalVersionedDbListener</code> provides a listener 
which maintains checkout and history data in response to 
VersionedDatabase callbacks.
Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/store/local/LocalDatabaseItem.java