@Test
 public void testByUserId() throws Exception {
   // get students table
   IDataSet databaseDataSet = getConnection().createDataSet();
   ITable actualTable = databaseDataSet.getTable("STUDENT");
   // tacking student id with user id = 3
   long studentId = (Long) actualTable.getValue(2, "id");
   // get student by tested method and check result
   while (studentDaoImpl.findByUserId(3) == null) {}
   Student student = studentDaoImpl.findByUserId(3);
   Assert.assertEquals(studentId, student.getId());
 }