@Test
public void getSessionNotExists() {
HttpServerExchange exchange = new HttpServerExchange(null);
Batcher<Batch> batcher = mock(Batcher.class);
Batch batch = mock(Batch.class);
SessionConfig config = mock(SessionConfig.class);
String sessionId = "session";
when(config.findSessionId(exchange)).thenReturn(sessionId);
when(this.manager.findSession(sessionId)).thenReturn(null);