*/

    @Override
    @ParametricNullness
    K checkKey(@ParametricNullness K key) {
      return super.inverse.checkValue(key);
    }

    @Override
    @ParametricNullness
    V checkValue(@ParametricNullness V value) {
      return super.inverse.checkKey(value);
    }

    /**
     * @serialData the forward bimap
     */
    @GwtIncompatible

  }

  /** Returns the associated value type. */
  @GwtIncompatible
  public Class<V> valueType() {
    return valueTypeOrObjectUnderJ2cl;
  }

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @Override
  V checkValue(V value) {
    return checkNotNull(value);
  }

  /**

    this.keyTypeOrObjectUnderJ2cl = keyType;
  }

  // Overriding these 3 methods to show that values may be null (but not keys)

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @CanIgnoreReturnValue
  @Override
  @SuppressWarnings("RedundantOverride") // b/192446478: RedundantOverride ignores some annotations.

      checkElementsNotNull(elements, n);
      ensureRoomFor(n);
      /*
       * The following call is not statically checked, since arraycopy accepts plain Object for its
       * parameters. If it were statically checked, the checker would still be OK with it, since
       * we're copying into a `contents` array whose type allows it to contain nulls. Still, it's

      } catch (Exception | Error unsafeFailure) { // sneaky checked exception
        thrownUnsafeFailure = unsafeFailure;
        // Catch absolutely everything and fall through to AtomicReferenceFieldUpdaterAtomicHelper.
        try {
          helper = new AtomicReferenceFieldUpdaterAtomicHelper();
        } catch (Exception // sneaky checked exception
            | Error atomicReferenceFieldUpdaterFailure) {

      } catch (Exception | Error unsafeFailure) { // sneaky checked exception
        thrownUnsafeFailure = unsafeFailure;
        // Catch absolutely everything and fall through to AtomicReferenceFieldUpdaterAtomicHelper.
        try {
          helper = new AtomicReferenceFieldUpdaterAtomicHelper();
        } catch (Exception // sneaky checked exception
            | Error atomicReferenceFieldUpdaterFailure) {

              public void close() throws IOException {
                super.close();
                counter[0]--;
              }
            };
          }
        };
    byte[] result = ByteSource.concat(checker, checker, checker).read();
    assertThat(result).hasLength(150);
  }

  private void joinHelper(Integer... spans) throws Exception {
    List<ByteSource> sources = new ArrayList<>();
    int start = 0;

not use beta APIs, unless you [repackage] them. **If your
code is a library, we strongly recommend using the [Guava Beta Checker] to
ensure that you do not use any `@Beta` APIs!**

[Guava Beta Checker]: https://github.com/google/guava-beta-checker

<!-- References -->

   *       RuntimeException} (though {@code get} implementations are discouraged from throwing such
   *       exceptions).
   * </ul>
   *
   * <p>The overall principle is to continue to treat every checked exception as a checked
   * exception, every unchecked exception as an unchecked exception, and every error as an error. In
   * addition, the cause of any {@code ExecutionException} is wrapped in order to ensure that the

     * This method is not supported in the Fess implementation.
     *
     * @param checker the credential checker to use
     * @throws UnsupportedOperationException always thrown as this method is not supported
     */
    @Override
    protected void checkCredential(final TypicalLoginAssist<String, FessUserBean, FessUser>.CredentialChecker checker) {