@Test
public void testFromDb() throws SchemaException, MapperException {

    LOG.info("testFromDb");
    Collection<String> db = null;
    Collection<?> mem;
    mem = mapper.fromDb(db);
    Assert.assertTrue(mem != null);
    Assert.assertTrue(mem.isEmpty());
    db = new ArrayList<>();
    mem = mapper.fromDb(db);
    Assert.assertTrue(mem != null);
    Assert.assertTrue(mem.isEmpty());
    db.add("red");
    mem = mapper.fromDb(db);
    Assert.assertTrue(mem != null);
    Assert.assertTrue(mem.size() == 1);
    Assert.assertEquals("red", mem.toArray()[0]);
    db.add("blue");
    mem = mapper.fromDb(db);
    Assert.assertTrue(mem != null);
    Assert.assertTrue(mem.size() == 2);
    Assert.assertEquals("red", mem.toArray()[0]);
    Assert.assertEquals("blue", mem.toArray()[1]);
}