EventExecutor Type — netty Architecture

Source Code

common/src/main/java/io/netty/util/concurrent/EventExecutor.java lines 27–114

public interface EventExecutor extends EventExecutorGroup, ThreadAwareExecutor {

    /**
     * Return the {@link EventExecutorGroup} which is the parent of this {@link EventExecutor},
     */
    EventExecutorGroup parent();

    @Override
    default boolean isExecutorThread(Thread thread) {
        return inEventLoop(thread);
    }

    /**
     * Calls {@link #inEventLoop(Thread)} with {@link Thread#currentThread()} as argument
     */
    default boolean inEventLoop() {
        return inEventLoop(Thread.currentThread());
    }

    /**
     * Return {@code true} if the given {@link Thread} is executed in the event loop,
     * {@code false} otherwise.
     */
    boolean inEventLoop(Thread thread);

    /**
     * Return a new {@link Promise}.
     */
    default <V> Promise<V> newPromise() {
        return new DefaultPromise<>(this);
    }

    /**
     * Create a new {@link ProgressivePromise}.
     */
    default <V> ProgressivePromise<V> newProgressivePromise() {
        return new DefaultProgressivePromise<>(this);
    }

    /**
     * Create a new {@link Future} which is marked as succeeded already. So {@link Future#isSuccess()}
     * will return {@code true}. All {@link FutureListener} added to it will be notified directly. Also
     * every call of blocking methods will just return without blocking.
     */
    default <V> Future<V> newSucceededFuture(V result) {
        return new SucceededFuture<>(this, result);
    }

    /**
     * Create a new {@link Future} which is marked as failed already. So {@link Future#isSuccess()}
     * will return {@code false}. All {@link FutureListener} added to it will be notified directly. Also
     * every call of blocking methods will just return without blocking.
     */
    default <V> Future<V> newFailedFuture(Throwable cause) {
        return new FailedFuture<>(this, cause);
    }

    /**
     * Returns {@code true} if the {@link EventExecutor} is considered suspended.
     *
     * @return {@code true} if suspended, {@code false} otherwise.
     */
    default boolean isSuspended() {
        return false;
    }

    /**
     * Try to suspend this {@link EventExecutor} and return {@code true} if suspension was successful.
     * Suspending an {@link EventExecutor} will allow it to free up resources, like for example a {@link Thread} that
     * is backing the {@link EventExecutor}. Once an {@link EventExecutor} was suspended it will be started again
     * by submitting work to it via one of the following methods:
     * <ul>
     *   <li>{@link #execute(Runnable)}</li>
     *   <li>{@link #schedule(Runnable, long, TimeUnit)}</li>
     *   <li>{@link #schedule(Callable, long, TimeUnit)}</li>
     *   <li>{@link #scheduleAtFixedRate(Runnable, long, long, TimeUnit)}</li>
     *   <li>{@link #scheduleWithFixedDelay(Runnable, long, long, TimeUnit)}</li>
     * </ul>
     *
     * Even if this method returns {@code true} it might take some time for the {@link EventExecutor} to fully suspend
     * itself.