bus = new AsyncEventBus(executor);
  }

  public void testBasicDistribution() {
    StringCatcher catcher = new StringCatcher();
    bus.register(catcher);

    // We post the event, but our Executor will not deliver it until instructed.
    bus.post(EVENT);

    List<String> events = catcher.getEvents();
    assertTrue("No events should be delivered synchronously.", events.isEmpty());

    requireNonNull(seq); // safe as long as we call this only after checkOpen
    return seq.length() - pos;
  }

  /*
   * To avoid the need to call requireNonNull so much, we could consider more clever approaches,
   * such as:
   *
   * - Make checkOpen return the non-null `seq`. Then callers can assign that to a local variable or
   *   even back to `this.seq`. However, that may suggest that we're defending against concurrent

 */

package com.google.common.util.concurrent;

import com.google.common.annotations.GwtCompatible;
import junit.framework.TestCase;

/**
 * Unit tests for {@link Runnables}.
 *
 * @author Olivier Pernet
 */
@GwtCompatible
public class RunnablesTest extends TestCase {
  public void testDoNothingRunnableIsSingleton() {
    assertSame(Runnables.doNothing(), Runnables.doNothing());
  }

 */

package com.google.common.util.concurrent;

import com.google.common.annotations.GwtCompatible;
import junit.framework.TestCase;

/**
 * Unit tests for {@link Runnables}.
 *
 * @author Olivier Pernet
 */
@GwtCompatible
public class RunnablesTest extends TestCase {
  public void testDoNothingRunnableIsSingleton() {
    assertSame(Runnables.doNothing(), Runnables.doNothing());
  }

    bus = new AsyncEventBus(executor);
  }

  public void testBasicDistribution() {
    StringCatcher catcher = new StringCatcher();
    bus.register(catcher);

    // We post the event, but our Executor will not deliver it until instructed.
    bus.post(EVENT);

    List<String> events = catcher.getEvents();
    assertTrue("No events should be delivered synchronously.", events.isEmpty());

   *
   * @return the source of this event.
   */
  public Object getSource() {
    return source;
  }

  /**
   * Returns the wrapped, 'dead' event, which the system was unable to deliver to any registered
   * subscriber.
   *
   * @return the 'dead' event that could not be delivered.
   */
  public Object getEvent() {
    return event;
  }

  @Override
  public String toString() {