}

  public void testFilterSimple() {
    Iterator<String> unfiltered = Lists.newArrayList("foo", "bar").iterator();
    Iterator<String> filtered = Iterators.filter(unfiltered, Predicates.equalTo("foo"));
    List<String> expected = Collections.singletonList("foo");
    List<String> actual = Lists.newArrayList(filtered);
    assertEquals(expected, actual);
  }

    assertTrue(set.isEmpty());
    set.add(new Derived("foo"));
    set.add(new Derived("bar"));
    assertThat(set).containsExactly(new Derived("bar"), new Derived("foo")).inOrder();
  }

  public void testNewTreeSetEmptyNonGeneric() {
    TreeSet<LegacyComparable> set = Sets.newTreeSet();
    assertTrue(set.isEmpty());
    set.add(new LegacyComparable("foo"));
    set.add(new LegacyComparable("bar"));
    assertThat(set)

  public void testImmutableEntry() {
    Entry<String, Integer> e = Maps.immutableEntry("foo", 1);
    assertEquals("foo", e.getKey());
    assertEquals(1, (int) e.getValue());
    try {
      e.setValue(2);
      fail("UnsupportedOperationException expected");
    } catch (UnsupportedOperationException expected) {
    }
    assertEquals("foo=1", e.toString());
    assertEquals(101575, e.hashCode());
  }

  public void testImmutableEntry() {
    Entry<String, Integer> e = Maps.immutableEntry("foo", 1);
    assertEquals("foo", e.getKey());
    assertEquals(1, (int) e.getValue());
    try {
      e.setValue(2);
      fail("UnsupportedOperationException expected");
    } catch (UnsupportedOperationException expected) {
    }
    assertEquals("foo=1", e.toString());
    assertEquals(101575, e.hashCode());
  }

      // if "formalType" is <? extends Foo>, "this" can be:
      // Foo, SubFoo, <? extends Foo>, <? extends SubFoo>, <T extends Foo> or
      // <T extends SubFoo>.
      // if "formalType" is <? super Foo>, "this" can be:
      // Foo, SuperFoo, <? super Foo> or <? super SuperFoo>.
      return every(your.getUpperBounds()).isSupertypeOf(runtimeType)

  }

  public void testFilterSimple() {
    Iterator<String> unfiltered = Lists.newArrayList("foo", "bar").iterator();
    Iterator<String> filtered = Iterators.filter(unfiltered, Predicates.equalTo("foo"));
    List<String> expected = Collections.singletonList("foo");
    List<String> actual = Lists.newArrayList(filtered);
    assertEquals(expected, actual);
  }

          public String load(String key) throws InterruptedException {
            callCount.incrementAndGet();
            secondSignal.countDown();
            computeSignal.await();
            return key + "foo";
          }
        };

    final LoadingCache<String, String> cache =
        CacheBuilder.newBuilder().weakKeys().build(computeFunction);

   *   Iterator<E> it = set.iterator();
   *   while (it.hasNext()) {
   *     foo(it.next());
   *   }
   * }
   * }</pre>
   *
   * <p>or:
   *
   * <pre>{@code
   * NavigableSet<E> set = synchronizedNavigableSet(new TreeSet<E>());
   * NavigableSet<E> set2 = set.descendingSet().headSet(foo);
   *  ...
   * synchronized (set) { // Note: set, not set2!!!

     * LF<? extends @Nullable V>. That might be better: There's currently no difference between the
     * outputs users get when calling this with <Foo> and calling it with <@Nullable Foo>. The only
     * difference is that calling it with <Foo> won't work when an input Future has a @Nullable
     * type. So why even make that error possible by giving callers the choice?
     *

          public String load(String key) throws InterruptedException {
            callCount.incrementAndGet();
            secondSignal.countDown();
            computeSignal.await();
            return key + "foo";
          }
        };

    final LoadingCache<String, String> cache =
        CacheBuilder.newBuilder().weakKeys().build(computeFunction);