"Shouldn't catch any more events when unregistered.", expectedEvents, catcher1.getEvents());
    assertEquals("Two correct events should be delivered.", expectedEvents, catcher2.getEvents());

    assertThrows(IllegalArgumentException.class, () -> bus.unregister(catcher1));

    bus.unregister(catcher2);
    bus.post(EVENT);
    assertEquals(

 * So, using the multimap shown above as an example, the {@link #size} is {@code 3}, not {@code 2},
 * and the {@link #values} collection is {@code [1, 2, 3]}, not {@code [[1, 2], [3]]}. For those
 * times when the first style is more useful, use the multimap's {@link #asMap} view (or create a
 * {@code Map<K, Collection<V>>} in the first place).
 *
 * <h3>Example</h3>
 *
 * <p>The following code:
 *
 * <pre>{@code

 * provided {@code standardAddAll} method.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingSortedSet}.
 *
 * <p>Each of the {@code standard} methods, where appropriate, uses the set's comparator (or the

public final class Runnables {

  private static final Runnable EMPTY_RUNNABLE =
      new Runnable() {
        @Override
        public void run() {}
      };

  /** Returns a {@link Runnable} instance that does nothing when run. */
  public static Runnable doNothing() {
    return EMPTY_RUNNABLE;
  }

  private Runnables() {}

   * Returns a new, empty builder for {@link ImmutableIntArray} instances, sized to hold up to
   * {@code initialCapacity} values without resizing. The returned builder is not thread-safe.
   *
   * <p><b>Performance note:</b> When feasible, {@code initialCapacity} should be the exact number
   * of values that will be added, if that knowledge is readily available. It is better to guess a

  // Run Enums.getIfPresent on that other TestEnum and then return a WeakReference containing the
  // new ClassLoader. If Enums.getIfPresent does caching that prevents the shadow TestEnum
  // (and therefore its ClassLoader) from being unloaded, then this WeakReference will never be
  // cleared.
  @J2ktIncompatible
  @GwtIncompatible // weak references

 * bad design, and it does not prevent anyone from using the declaration---and experience has shown
 * that they will. If the method breaks the encapsulation of its class, then its internal
 * representation will be hard to change. Instead, use <a
 * href="http://errorprone.info/bugpattern/RestrictedApi">RestrictedApiChecker</a>, which enforces
 * fine-grained visibility policies.
 *

  private EmptyImmutableListMultimap() {
    super(ImmutableMap.<Object, ImmutableList<Object>>of(), 0);
  }

  /*
   * TODO(b/242884182): Figure out why this helps produce the same class file when we compile most
   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */

   * return the cause of the failure. "Failure" means specifically "completed with an exception"; it
   * does not include "was cancelled." To be explicit: If this method returns a non-null value,
   * then:
   *
   * <ul>
   *   <li>{@code isDone()} must return {@code true}
   *   <li>{@code isCancelled()} must return {@code false}
   *   <li>{@code get()} must not block, and it must throw an {@code ExecutionException} with the

   * Returns a new, empty builder for {@link ImmutableDoubleArray} instances, sized to hold up to
   * {@code initialCapacity} values without resizing. The returned builder is not thread-safe.
   *
   * <p><b>Performance note:</b> When feasible, {@code initialCapacity} should be the exact number
   * of values that will be added, if that knowledge is readily available. It is better to guess a