private void validateUser(String currentUser) throws UserAccessException {
		if (!userMgr.isValidUser(currentUser)) {
			throw new UserAccessException(currentUser + " is unknown to this repository manager");
		}
	}
Verify that the specified currentUser is a known user
@param currentUser current user
@throws UserAccessException specified user is not valid
Ghidra/Features/GhidraServer/src/main/java/ghidra/server/RepositoryManager.java