object.set("sid", 257L);
assertThat(object.get("sid"), eq(257L));
object.set("value", new Text("Hello, DMDL!"));
assertThat(object.get("value"), eq(new Text("Hello, DMDL!")));
PrimaryKey pk = object.unwrap().getClass().getAnnotation(PrimaryKey.class);
assertThat(pk, not(nullValue()));
assertThat(pk.value(), is(new String[] { "sid" }));
}