/**
 * A list multimap which forwards all its method calls to another list multimap. Subclasses should
 * override one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

/**
 * A sorted set multimap which forwards all its method calls to another sorted set multimap.
 * Subclasses should override one or more methods to modify the behavior of the backing multimap as
 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

    // Cancel some calls. That doesn't impact running or queued.
    a2.cancel()
    a3.cancel()
    assertThat(dispatcher.runningCalls())
      .containsExactlyInAnyOrder(a1, a2)
    assertThat(dispatcher.queuedCalls()).isEmpty()

    // Let the calls finish.
    waiting.countDown()
    t1.join()
    t2.join()

    // Now we should have 0 running calls and 0 queued calls.

/**
 * A listening executor service which forwards all its method calls to another listening executor
 * service. Subclasses should override one or more methods to modify the behavior of the backing
 * executor service as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

     * <p>
     * If a root package is specified at instance construction, only classes under the root package are targeted.
     * </p>
     *
     * @param handler the handler to process classes
     */
    void forEach(ClassHandler handler);

    /**
     * Searches for resources handled by this instance and calls the handler for each resource.
     * <p>

@GwtCompatible
public interface PeekingIterator<E extends @Nullable Object> extends Iterator<E> {
  /**
   * Returns the next element in the iteration, without advancing the iteration.
   *
   * <p>Calls to {@code peek()} should not change the state of the iteration, except that it
   * <i>may</i> prevent removal of the most recent element via {@link #remove()}.
   *

 * A concurrent map which forwards all its method calls to another concurrent map. Subclasses should
 * override one or more methods to modify the behavior of the backing map as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class forwards calls to <i>only some</i> {@code
 * default} methods. Specifically, it forwards calls only for methods that existed <a

/**
 * A list multimap which forwards all its method calls to another list multimap. Subclasses should
 * override one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

/**
 * A {@link BlockingQueue} which forwards all its method calls to another {@link BlockingQueue}.
 * Subclasses should override one or more methods to modify the behavior of the backing collection
 * as desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator
 * pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

/**
 * An iterator which forwards all its method calls to another iterator. Subclasses should override
 * one or more methods to modify the behavior of the backing iterator as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class forwards calls to <i>only some</i> {@code
 * default} methods. Specifically, it forwards calls only for methods that existed <a