assertTrue(Arrays.equals(new String[] {"a"}, array));
  }

  @GwtIncompatible // Iterators.toArray(Iterator, Class)
  public void testToArray() {
    String[] sourceArray = new String[] {"a", "b", "c"};
    Iterator<String> iterator = asList(sourceArray).iterator();
    String[] newArray = Iterators.toArray(iterator, String.class);
    assertTrue(Arrays.equals(sourceArray, newArray));
  }

   *     string using {@link String#valueOf(Object)}
   * @throws IllegalArgumentException if {@code expression} is false
   */
  public static void checkArgument(boolean expression, @CheckForNull Object errorMessage) {
    if (!expression) {
      throw new IllegalArgumentException(String.valueOf(errorMessage));
    }
  }

  /**

    final CountDownLatch getFinishedSignal = new CountDownLatch(2);
    final String getKey = "get";
    final String refreshKey = "refresh";
    final String suffix = "Suffix";

    CacheLoader<String, String> computeFunction =
        new CacheLoader<String, String>() {
          @Override
          public String load(String key) throws InterruptedException {
            getStartedSignal.countDown();

                  @Override
                  protected Set<String> create(String[] elements) {
                    SafeTreeSet<String> set = new SafeTreeSet<>(Arrays.asList(elements));
                    return Sets.unmodifiableNavigableSet(set);
                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {

        new EntryTransformer<String, String, String>() {
          @Override
          public String transformEntry(String key, String value) {
            return key + value;
          }
        };
    SortedMap<String, String> transformed = transformEntries(map, concat);

    /*
     * We'd like to sanity check that we didn't get a NavigableMap out, but we

        new EntryTransformer<String, String, String>() {
          @Override
          public String transformEntry(String key, String value) {
            return key + value;
          }
        };
    SortedMap<String, String> transformed = transformEntries(map, concat);

    /*
     * We'd like to sanity check that we didn't get a NavigableMap out, but we

    final CountDownLatch getFinishedSignal = new CountDownLatch(2);
    final String getKey = "get";
    final String refreshKey = "refresh";
    final String suffix = "Suffix";

    CacheLoader<String, String> computeFunction =
        new CacheLoader<String, String>() {
          @Override
          public String load(String key) throws InterruptedException {
            getStartedSignal.countDown();

   * maps ("constant maps"). Example:
   *
   * <pre>{@code
   * static final ImmutableSortedMap<Integer, String> INT_TO_WORD =
   *     new ImmutableSortedMap.Builder<Integer, String>(Ordering.natural())
   *         .put(1, "one")
   *         .put(2, "two")
   *         .put(3, "three")
   *         .buildOrThrow();
   * }</pre>
   *

    class Local<T> {}
    TypeToken<Local<String>> type = new TypeToken<Local<String>>() {};
    assertEquals(Types.newParameterizedType(Local.class, String.class), type.getType());
    assertEquals(new Local<String>() {}.getClass().getGenericSuperclass(), type.getType());
  }

  public void testGenericArrayType() {
    TypeToken<List<String>[]> token = new TypeToken<List<String>[]>() {};

                    TestCloseable, String, String, String, String, TestCloseable>() {
                  @Override
                  public TestCloseable apply(
                      DeferredCloser closer,
                      TestCloseable v1,
                      String v2,
                      String v3,
                      String v4,
                      String v5)
                      throws Exception {