## Integrated middlewares { #integrated-middlewares }

**FastAPI** includes several middlewares for common use cases, we'll see next how to use them.

/// note | Technical Details

For the next examples, you could also use `from starlette.middleware.something import SomethingMiddleware`.

        when(delegate.hasNext()).thenReturn(true, true, false);
        when(delegate.next()).thenReturn(bad, good);

        NetServerFileEntryAdapterIterator itr = new NetServerFileEntryAdapterIterator(parent, delegate, null);

        // Act: first valid next should be the second element
        assertTrue(itr.hasNext());
        SmbResource r = itr.next();

        // Assert: the invalid name was skipped, valid one returned

   * a CountdownLatch).
   */
  @Throws(InterruptedException::class)
  public abstract fun dispatch(request: RecordedRequest): MockResponse

  /**
   * Returns an early guess of the next response, used for policy on how an incoming request should
   * be received. The default implementation returns an empty response. Mischievous implementations

              Entry<? extends E> entry1 = iterator1.next();
              E element = entry1.getElement();
              int count = max(entry1.getCount(), multiset2.count(element));
              return immutableEntry(element, count);
            }
            while (iterator2.hasNext()) {
              Entry<? extends E> entry2 = iterator2.next();
              E element = entry2.getElement();

              Entry<? extends E> entry1 = iterator1.next();
              E element = entry1.getElement();
              int count = max(entry1.getCount(), multiset2.count(element));
              return immutableEntry(element, count);
            }
            while (iterator2.hasNext()) {
              Entry<? extends E> entry2 = iterator2.next();
              E element = entry2.getElement();

  @Override
  public final boolean hasNext() {
    return backingIterator.hasNext();
  }

  @Override
  @ParametricNullness
  public final T next() {
    return transform(backingIterator.next());
  }

  @Override
  public final void remove() {
    backingIterator.remove();
  }

        assertEquals(1, violations.size());
        assertTrue(violations.iterator().next().getPropertyPath().toString().contains("defaultCron"));

        // Validate special group
        violations = validator.validate(bean, SpecialGroup.class);
        assertEquals(1, violations.size());
        assertTrue(violations.iterator().next().getPropertyPath().toString().contains("specialCron"));

        // Validate all groups

    assertTrue(iterator.hasNext());
    assertThat(iterator.next()).isEqualTo("a");
    assertThrows(UnsupportedOperationException.class, () -> iterator.remove());
  }

  @SuppressWarnings("DoNotCall")
  public void testAdd() {
    ListIterator<String> iterator = create();

    assertTrue(iterator.hasNext());
    assertThat(iterator.next()).isEqualTo("a");
    assertThat(iterator.next()).isEqualTo("b");

    assertTrue(iterator.hasNext());
    assertThat(iterator.next()).isEqualTo("a");
    assertThrows(UnsupportedOperationException.class, () -> iterator.remove());
  }

  @SuppressWarnings("DoNotCall")
  public void testAdd() {
    ListIterator<String> iterator = create();

    assertTrue(iterator.hasNext());
    assertThat(iterator.next()).isEqualTo("a");
    assertThat(iterator.next()).isEqualTo("b");

        return doMove(form, -1);
    }

    /**
     * Navigates to the next page of search results.
     *
     * @param form the list form containing current search criteria
     * @return HTML response with next page results
     */
    @Execute
    @Secured({ ROLE, ROLE + VIEW })
    public HtmlResponse next(final ListForm form) {
        saveToken();
        return doMove(form, 1);
    }