@Test
public void testLoadFromJackson() throws Exception {

    String myJson = "{\"2\":[\"ABCDEF\"],\"4\":[\"FEDCEB\"]}";
    TeamTagMap result = Serialization.getJsonMapper().readValue(myJson, TeamTagMap.class);
    assertThat(result.tagToTeam(new TagId("ABCDEF")), equalTo(Optional.of(2)));
    assertThat(result.tagToTeam(new TagId("FEDCEB")), equalTo(Optional.of(4)));
}