Supplier<Integer> memoizedSupplier =
        Suppliers.memoizeWithExpiration(countingSupplier, Duration.ofMillis(75));

    checkExpiration(countingSupplier, memoizedSupplier);
  }

  @SuppressWarnings("DoNotCall")
  public void testMemoizeWithExpiration_longTimeUnitNegative() throws InterruptedException {
    try {
      Supplier<String> unused = Suppliers.memoizeWithExpiration(() -> "", 0, TimeUnit.MILLISECONDS);
      fail();

    Supplier<Integer> memoizedSupplier =
        Suppliers.memoizeWithExpiration(countingSupplier, Duration.ofMillis(75));

    checkExpiration(countingSupplier, memoizedSupplier);
  }

  @SuppressWarnings("DoNotCall")
  public void testMemoizeWithExpiration_longTimeUnitNegative() throws InterruptedException {
    try {
      Supplier<String> unused = Suppliers.memoizeWithExpiration(() -> "", 0, TimeUnit.MILLISECONDS);
      fail();

   * @throws IllegalArgumentException if {@code duration} is not positive
   * @since 2.0
   */
  @SuppressWarnings("GoodTime") // Prefer the Duration overload
  public static <T extends @Nullable Object> Supplier<T> memoizeWithExpiration(
      Supplier<T> delegate, long duration, TimeUnit unit) {
    checkNotNull(delegate);
    checkArgument(duration > 0, "duration (%s %s) must be > 0", duration, unit);

   * @throws IllegalArgumentException if {@code duration} is not positive
   * @since 2.0
   */
  @SuppressWarnings("GoodTime") // Prefer the Duration overload
  public static <T extends @Nullable Object> Supplier<T> memoizeWithExpiration(
      Supplier<T> delegate, long duration, TimeUnit unit) {
    checkNotNull(delegate);
    checkArgument(duration > 0, "duration (%s %s) must be > 0", duration, unit);