*/
  @Override
  public ImmutableSetMultimap<V, K> inverse() {
    ImmutableSetMultimap<V, K> result = inverse;
    return (result == null) ? (inverse = invert()) : result;
  }

  private ImmutableSetMultimap<V, K> invert() {
    Builder<V, K> builder = builder();
    for (Entry<K, V> entry : entries()) {
      builder.put(entry.getValue(), entry.getKey());
    }

      // we're given a bad one. We only catch Exception because we want Errors to propagate up.
      log.get()
          .log(
              Level.SEVERE,
              "RuntimeException while executing runnable "
                  + runnable
                  + " with executor "
                  + executor,
              e);
    }
  }

    // shouldn't break in cases where reflection is missing/broken.
    if (thrownAtomicReferenceFieldUpdaterFailure != null) {
      log.get().log(Level.SEVERE, "UnsafeAtomicHelper is broken!", thrownUnsafeFailure);
      log.get()
          .log(
              Level.SEVERE,
              "SafeAtomicHelper is broken!",
              thrownAtomicReferenceFieldUpdaterFailure);
    }
  }

   *     separator
   */
  public abstract BaseEncoding withPadChar(char padChar);

  /**
   * Returns an encoding that behaves equivalently to this encoding, but adds a separator string
   * after every {@code n} characters. Any occurrences of any characters that occur in the separator
   * are skipped over in decoding.
   *
   * @throws IllegalArgumentException if any alphabet or padding characters appear in the separator

          checkElementIndex(index, size());
          return rest[index - 2];
      }
    }

    @J2ktIncompatible private static final long serialVersionUID = 0;
  }

  /**
   * Returns every possible list that can be formed by choosing one element from each of the given
   * lists in order; the "n-ary <a href="http://en.wikipedia.org/wiki/Cartesian_product">Cartesian
   * product</a>" of the lists. For example:
   *

  @SuppressWarnings("unchecked")
  protected B self() {
    return (B) this;
  }

  // Test Data

  private @Nullable G subjectGenerator;
  // Gets run before every test.
  private Runnable setUp;
  // Gets run at the conclusion of every test.
  private Runnable tearDown;

  @CanIgnoreReturnValue
  protected B usingGenerator(G subjectGenerator) {
    this.subjectGenerator = subjectGenerator;
    return self();

   * time a task is submitted.
   *
   * <p>When an {@code Error} is thrown by an executed task, previously submitted tasks may never
   * run. An attempt will be made to restart execution on the next call to {@code execute}. If the
   * {@code delegate} has begun to reject execution, the previously submitted tasks may never run,
   * despite not throwing a RejectedExecutionException synchronously with the call to {@code

    throw new AssertionError("should never be called");
  }

  @Override
  public ImmutableCollection<V> values() {
    return (ImmutableCollection<V>) super.values();
  }

  @Override
  abstract ImmutableCollection<V> createValues();

  @Override
  final Iterator<V> valuesIterator() {
    throw new AssertionError("should never be called");
  }

  /**
   * {@inheritDoc}

    /** Gets the weak value reference held by entry. */
    WeakValueReference<K, V, E> getValueReference();
  }

  @SuppressWarnings("unchecked") // impl never uses a parameter or returns any non-null value
  static <K, V, E extends InternalEntry<K, V, E>>
      WeakValueReference<K, V, E> unsetWeakValueReference() {
    return (WeakValueReference<K, V, E>) UNSET_WEAK_VALUE_REFERENCE;

import java.util.stream.Collector;
import java.util.stream.Collectors;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link BiMap} whose contents will never change, with many other important properties detailed
 * at {@link ImmutableCollection}.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible(serializable = true, emulated = true)
@ElementTypesAreNonnullByDefault