### Question:
Tags { public static Tags empty() { return EMPTY_TAGS; } private  Tags(SortedMap<String, SortedSet<Object>> map); static Builder builder(); static Tags empty(); static Tags of(String name, String value); static Tags of(String name, boolean value); static Tags of(String name, long value); static Tags of(String name, double value); SortedMap<String, SortedSet<Object>> asMap(); boolean isEmpty(); Tags merge(Tags other); @Override boolean equals(@NullableDecl Object obj); @Override int hashCode(); @Override String toString();  }### Answer:
@Test public void testEmpty() { assertThat(Tags.builder().build()).isSameInstanceAs(Tags.empty()); }