@Test
public void testGet() throws Exception {

    Map<String,String> m1 = new HashMap<>();
    Map<String,String> m2 = new HashMap<>();
    m1.put("a", String.valueOf(1L));
    m2.put("b", "c");
    MultiMapLookup mml = new MultiMapLookup(m1, m2);
    assertThat(mml.get("a")).isEqualTo("1");
}