ScheduledFutureTask Class — netty Architecture

Source Code

common/src/main/java/io/netty/util/concurrent/ScheduledFutureTask.java lines 26–227

@SuppressWarnings("ComparableImplementedButEqualsNotOverridden")
final class ScheduledFutureTask<V> extends PromiseTask<V> implements ScheduledFuture<V>, PriorityQueueNode {
    // set once when added to priority queue
    private long id;

    private long deadlineNanos;
    /* 0 - no repeat, >0 - repeat at fixed rate, <0 - repeat with fixed delay */
    private final long periodNanos;

    private int queueIndex = INDEX_NOT_IN_QUEUE;

    ScheduledFutureTask(AbstractScheduledEventExecutor executor,
            Runnable runnable, long nanoTime) {

        super(executor, runnable);
        deadlineNanos = nanoTime;
        periodNanos = 0;
    }

    ScheduledFutureTask(AbstractScheduledEventExecutor executor,
            Runnable runnable, long nanoTime, long period) {

        super(executor, runnable);
        deadlineNanos = nanoTime;
        periodNanos = validatePeriod(period);
    }

    ScheduledFutureTask(AbstractScheduledEventExecutor executor,
            Callable<V> callable, long nanoTime, long period) {

        super(executor, callable);
        deadlineNanos = nanoTime;
        periodNanos = validatePeriod(period);
    }

    ScheduledFutureTask(AbstractScheduledEventExecutor executor,
            Callable<V> callable, long nanoTime) {

        super(executor, callable);
        deadlineNanos = nanoTime;
        periodNanos = 0;
    }

    private static long validatePeriod(long period) {
        if (period == 0) {
            throw new IllegalArgumentException("period: 0 (expected: != 0)");
        }
        return period;
    }

    ScheduledFutureTask<V> setId(long id) {
        if (this.id == 0L) {
            this.id = id;
        }
        return this;
    }

    long getId() {
        return id;
    }

    @Override
    protected EventExecutor executor() {
        return super.executor();
    }

    public long deadlineNanos() {
        return deadlineNanos;
    }

    void setConsumed() {
        // Optimization to avoid checking system clock again
        // after deadline has passed and task has been dequeued
        if (periodNanos == 0) {
            assert scheduledExecutor().getCurrentTimeNanos() >= deadlineNanos;
            deadlineNanos = 0L;
        }
    }

    public long delayNanos() {
        if (deadlineNanos == 0L) {