@After
  public void after() throws AmbariException, SQLException {
    H2DatabaseCleaner.clearDatabaseAndStopPersistenceService(injector);
    injector = null;
  }
Test the {@link HostVersionDAO#findByClusterStackVersionAndHost(String, StackId, String, String)} method.
ambari-server/src/test/java/org/apache/ambari/server/orm/dao/HostVersionDAOTest.java