<img src="/img/tutorial/separate-openapi-schemas/image02.png">
</div>

This means that it will **always have a value**, it's just that sometimes the value could be `None` (or `null` in JSON).

That means that, clients using your API don't have to check if the value exists or not, they can **assume the field will always be there**, but just that in some cases it will have the default value of `None`.

   * them under J2CL—or, as an unfortunate side effect, under GWT. We do still give the fields
   * themselves their proper values under GWT, since GWT's EnumMap does need the Class instance.
   *
   * Note that sometimes these fields *do* have correct values under J2CL: They will if the caller
   * calls `create(Foo.class)`, rather than `create(map)`. That's fine; we just shouldn't rely on
   * it.
   */

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

                // Clear sensitive data
                if (this.sessionKey != null) {
                    java.util.Arrays.fill(this.sessionKey, (byte) 0);
                    this.sessionKey = null;
                }

                if (this.preauthIntegrityHash != null) {
                    java.util.Arrays.fill(this.preauthIntegrityHash, (byte) 0);
                    this.preauthIntegrityHash = null;
                }

The StorageProtection feature, which prevents deletion of PVCs while Pods are still using them and of PVs while still bound to a PVC, is now generally available, and volume resizing, which lets you increase size of a volume after a Pod restarts is now beta, which means it is on by default.

New alpha features include:
* Online volume resizing will increase the filesystem size of a resized volume without requiring a Pod restart.

      Iterable<E> expectedElements,
      KnownOrder knownOrder,
      int startIndex) {
    // periodically we should manually try (steps * 3 / 2) here; all tests but
    // one should still pass (testVerifyGetsCalled()).
    stimuli = (Stimulus<E, ? super I>[]) new Stimulus<?, ?>[steps];
    if (!elementsToInsertIterable.iterator().hasNext()) {
      throw new IllegalArgumentException();
    }

    ticker.advance(ttl * 2 / 3, MILLISECONDS);

    assertEquals(10, CacheTesting.expirationQueueSize(cache));
    assertEquals(10, removalListener.getCount());

    // check that new values are still there - they still have 10 ms to live
    for (int i = 0; i < 10; i++) {
      loader.reset();
      assertEquals(Integer.valueOf(i + shift2), cache.getUnchecked(keyPrefix + i));

  private val pingIntervalMillis: Long,
  /**
   * For clients this is initially null, and will be assigned to the agreed-upon extensions. For
   * servers, it should be the agreed-upon extensions immediately.
   */
  private var extensions: WebSocketExtensions?,
  /** If compression is negotiated, outbound messages of this size and larger will be compressed. */
  private var minimumDeflateSize: Long,
  private val webSocketCloseTimeout: Long,

        PrefixQuery prefixQuery = new PrefixQuery(new Term("title", ""));

        QueryBuilder builder = queryProcessor.execute(context, prefixQuery, 1.0f);

        assertNotNull(builder);
        // Empty prefix should still create a valid query
        assertTrue(builder instanceof MatchPhrasePrefixQueryBuilder);

        MatchPhrasePrefixQueryBuilder mpqb = (MatchPhrasePrefixQueryBuilder) builder;
        assertEquals("", mpqb.value());

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *