Using Apache Mina as a Mock/In Memory SFTP Server for Unit Testing

I am having a bit of trouble working out how to use Apache Mina. Their documentation is a bit scant for my talentless brain to work out. I have seen the helpful starting code at Java SFTP server library?

What I can't figure out is how to use it. I want to setup a unit test that checks my sftp code, using Mina as a kind of mock server, i.e., be able to write a unit test like:

@Before 
public void beforeTestSetup() {
    sshd = SshServer.setUpDefaultServer();
    sshd.setPort(22);
    sshd.setKeyPairProvider(new SimpleGeneratorHostKeyProvider("hostkey.ser"));

    List<NamedFactory<UserAuth>> userAuthFactories = new ArrayList<NamedFactory<UserAuth>>();
    userAuthFactories.add(new UserAuthNone.Factory());
    sshd.setUserAuthFactories(userAuthFactories);
    sshd.setPublickeyAuthenticator(new PublickeyAuthenticator());


    sshd.setCommandFactory(new ScpCommandFactory());

    List<NamedFactory<Command>> namedFactoryList = new ArrayList<NamedFactory<Command>>();
    namedFactoryList.add(new SftpSubsystem.Factory());
    sshd.setSubsystemFactories(namedFactoryList);

    try {
        sshd.start();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Test
public void testGetFile() {

}

The question is what to put in testGetFile().

I've been trawling through the test code wondering whether more configuration is needed in the above to specify a root directory, a user name and an authentication key file name. Then I'll need to get and pull files from it using a client, or my own SFTP api code?

I'm sure this is an excellent API, there's just not a lot of instruction for it, can anyone help?