ImmutableSetMultimapTest.java 文件源码

public void testFlatteningToImmutableSetMultimap() {
  Collector<String, ?, ImmutableSetMultimap<Character, Character>> collector =
      ImmutableSetMultimap.flatteningToImmutableSetMultimap(
          str -> str.charAt(0), str -> str.substring(1).chars().mapToObj(c -> (char) c));
  BiPredicate<Multimap<?, ?>, Multimap<?, ?>> equivalence =
      Equivalence.equals()
          .onResultOf((Multimap<?, ?> mm) -> ImmutableList.copyOf(mm.asMap().entrySet()))
          .and(Equivalence.equals());
  ImmutableSetMultimap<Character, Character> empty = ImmutableSetMultimap.of();
  ImmutableSetMultimap<Character, Character> filled =
      ImmutableSetMultimap.<Character, Character>builder()
          .putAll('b', Arrays.asList('a', 'n', 'a', 'n', 'a'))
          .putAll('a', Arrays.asList('p', 'p', 'l', 'e'))
          .putAll('c', Arrays.asList('a', 'r', 'r', 'o', 't'))
          .putAll('a', Arrays.asList('s', 'p', 'a', 'r', 'a', 'g', 'u', 's'))
          .putAll('c', Arrays.asList('h', 'e', 'r', 'r', 'y'))
          .build();
  CollectorTester.of(collector, equivalence)
      .expectCollects(empty)
      .expectCollects(filled, "banana", "apple", "carrot", "asparagus", "cherry");
}