/**
 * The window specification for fixed size windows that is used to define window boundaries and grace period.
 * <p>
 * Grace period defines how long to wait on out-of-order events. That is, windows will continue to accept new records until {@code stream_time >= window_end + grace_period}.
 * Records that arrive after the grace period passed are considered <em>late</em> and will not be processed but are dropped.
 *
 * @param <W> type of the window instance
 */
public interface FixedSizeWindowDefinition<W extends Window> {


    /**
     * List all possible windows that contain the provided timestamp,
     * indexed by non-negative window start timestamps.
     *
     * @param timestamp the timestamp window should get created for
     * @return a map of {@code windowStartTimestamp -> Window} entries
     */
    Map<Long, W> windowsFor(final long timestamp);

    /**
     * Return the size of the specified windows in milliseconds.
     *
     * @return the size of the specified windows
     */
    long size();

    /**
     * Return the window grace period (the time to admit
     * out-of-order events after the end of the window.)
     *
     * Delay is defined as (stream_time - record_timestamp).
     */
    long gracePeriodMs();
}

@SuppressWarnings("deprecation") // Remove this suppression when Windows is removed
public final class TimeWindows extends Windows<TimeWindow> implements FixedSizeWindowDefinition<TimeWindow> {
// ... nothing else needs to change
}

@SuppressWarnings("deprecation") // Remove this suppression when Windows is removed
public final class UnlimitedWindows extends Windows<UnlimitedWindow> implements FixedSizeWindowDefinition<UnlimitedWindow> {
// ... nothing else needs to change
}

/**
 * ... the javadoc doesn't change
 *
 * @deprecated since 2.7 Implement FixedSizeWindowDefinition instead.
 */
@Deprecated
public abstract class Windows<W extends Window> implements FixedSizeWindowDefinition<W> {
// ... nothing else changes
}