* not be modifiable. When modification isn't supported, those methods will throw an {@link
 * UnsupportedOperationException}.
 *
 * <h3>Implementations</h3>
 *
 * <ul>
 *   <li>{@link ImmutableTable}
 *   <li>{@link HashBasedTable}
 *   <li>{@link TreeBasedTable}
 *   <li>{@link ArrayTable}
 *   <li>{@link Tables#newCustomTable Tables.newCustomTable}
 * </ul>

 *         .transform(User::getId, directExecutor())
 *         .transform(ActivityService::isLoggedIn, threadPool)
 *         .catching(RpcException.class, e -> false, directExecutor());
 * }
 *
 * <h3>Alternatives</h3>
 *
 * <h4>Frameworks</h4>
 *
 * <p>When chaining together a graph of asynchronous operations, you will often find it easier to
 * use a framework. Frameworks automate the process, often adding features like monitoring,

 * not be modifiable. When modification isn't supported, those methods will throw an {@link
 * UnsupportedOperationException}.
 *
 * <h3>Implementations</h3>
 *
 * <ul>
 *   <li>{@link ImmutableTable}
 *   <li>{@link HashBasedTable}
 *   <li>{@link TreeBasedTable}
 *   <li>{@link ArrayTable}
 *   <li>{@link Tables#newCustomTable Tables.newCustomTable}
 * </ul>

 * </ul>
 *
 * <p>Several lesser-used features are currently available only as static methods on the {@link
 * Iterables} class.
 *
 * <p><a id="streams"></a>
 *
 * <h3>Comparison to streams</h3>
 *
 * <p>{@link Stream} is similar to this class, but generally more powerful, and certainly more
 * standard. Key differences include:
 *
 * <ul>

 * </ol>
 *
 * <h3>Starting a pipeline</h3>
 *
 * Start a {@code ClosingFuture} pipeline {@linkplain #submit(ClosingCallable, Executor) from a
 * callable block} that may capture objects for later closing. To start a pipeline from a {@link
 * ListenableFuture} that doesn't create resources that should be closed later, you can use {@link
 * #from(ListenableFuture)} instead.
 *
 * <h3>Derived steps</h3>
 *

 * element (in a way that affects its {@link Object#equals} behavior) while it is contained in a
 * multiset. Undefined behavior and bugs will result.
 *
 * <h3>Implementations</h3>
 *
 * <ul>
 *   <li>{@link ImmutableMultiset}
 *   <li>{@link ImmutableSortedMultiset}
 *   <li>{@link HashMultiset}
 *   <li>{@link LinkedHashMultiset}
 *   <li>{@link TreeMultiset}

 * shared state without additional synchronization necessary for visibility to later executions of
 * the life cycle methods.
 *
 * <h3>Usage Example</h3>
 *
 * <p>Here is a sketch of a service which crawls a website and uses the scheduling capabilities to
 * rate limit itself.
 *
 * {@snippet :
 * class CrawlingService extends AbstractScheduledService {

 * element (in a way that affects its {@link Object#equals} behavior) while it is contained in a
 * multiset. Undefined behavior and bugs will result.
 *
 * <h3>Implementations</h3>
 *
 * <ul>
 *   <li>{@link ImmutableMultiset}
 *   <li>{@link ImmutableSortedMultiset}
 *   <li>{@link HashMultiset}
 *   <li>{@link LinkedHashMultiset}
 *   <li>{@link TreeMultiset}

 * shared state without additional synchronization necessary for visibility to later executions of
 * the life cycle methods.
 *
 * <h3>Usage Example</h3>
 *
 * <p>Here is a sketch of a service which crawls a website and uses the scheduling capabilities to
 * rate limit itself.
 *
 * {@snippet :
 * class CrawlingService extends AbstractScheduledService {

Wt = SIGMA1(Wt-2) + SIGMA0(Wt-15) + Wt-16; for 16 <= t <= 63 // // a = H0 // b = H1 // c = H2 // d = H3 // e = H4 // f = H5 // g = H6 // h = H7 // // for t = 0 to 63 { // T1 = h + BIGSIGMA1(e) + Ch(e,f,g) + Kt + Wt // T2 = BIGSIGMA0(a) + Maj(a,b,c) // h = g // g = f // f = e // e = d + T1 // d = c // c = b // b = a // a = T1 + T2 // } // // H0 = a + H0 // H1 = b + H1 // H2 = c + H2 // H3 = d + H3 // H4 = e + H4 // H5 = f + H5 // H6 = g + H6 // H7 = h + H7 // Wt = Mt; for 0 <= t <= 15 #define MSGSCHEDULE0(index)...