Windows {
	//Existing methods. Will be deprecated.
	public Windows<W> until(final long durationMs) throws IllegalArgumentException;
	public long maintainMs();
	public abstract long size();

	//New methods.
	public Windows<W> until(final Duration duration) throws IllegalArgumentException;
	public Duration maintain();
	public abstract Duration size();
}

class Window {
	//Existing methods. Will be deprecated.
	public Window(final long startMs, final long endMs) throws IllegalArgumentException;
	public long start();
	public long end();

	//New methods.
	public Window(final Instant start, final Instant end) throws IllegalArgumentException;
	public LocalDateTime start();
	public LocalDateTime end();
}

JoinWindows {
    //Existing methods. Will be deprecated.
    public static JoinWindows of(final long timeDifferenceMs) throws IllegalArgumentException;
    public JoinWindows before(final long timeDifferenceMs) throws IllegalArgumentException;
    public JoinWindows after(final long timeDifferenceMs) throws IllegalArgumentException;
    public JoinWindows until(final long durationMs) throws IllegalArgumentException;
    public long maintainMs();

    //New methods.
    public static JoinWindows of(final Duration timeDifference) throws IllegalArgumentException;
    public JoinWindows before(final Duration timeDifference) throws IllegalArgumentException;
    public JoinWindows after(final Duration timeDifference) throws IllegalArgumentException;
    public JoinWindows until(final Duration duration) throws IllegalArgumentException;
    public Duration maintain();
}

SessionWindows {
	//Existing methods. Will be deprecated.
    public static SessionWindows with(final long inactivityGapMs);
    public SessionWindows until(final long durationMs) throws IllegalArgumentException;
    public long inactivityGap();
    public long maintainMs();

	//New methods.
    public static SessionWindows with(final Duration inactivityGap);
    public SessionWindows until(final Duration duration) throws IllegalArgumentException;
    public Duration inactivityGap();
    public Duration maintain();
}

TimeWindowedDeserializer {
	//Existing methods. Will be deprecated.
	public TimeWindowedDeserializer(final Deserializer<T> inner, final long windowSize);
	public Long getWindowSize();

	//New methods.
	public TimeWindowedDeserializer(final Deserializer<T> inner, final Duration windowSize);
	public Duration getWindowSize();
}

TimeWindows {
	//Existing methods. Will be deprecated.
	public static TimeWindows of(final long sizeMs) throws IllegalArgumentException;
	public TimeWindows advanceBy(final long advanceMs);
	public Map<Long, TimeWindow> windowsFor(final long timestamp);
    public long size();
    public TimeWindows until(final long durationMs) throws IllegalArgumentException;
    public long maintainMs();

	//New methods.
	public static TimeWindows of(final Duration size) throws IllegalArgumentException;
	public TimeWindows advanceBy(final Duration advance);
	public Map<Long, TimeWindow> windowsFor(Instant timestamp);
    public Duration size();
    public TimeWindows until(final Duration duration) throws IllegalArgumentException;
    public Duration maintain();
}

UnlimitedWindows {
	//Existing methods. Will be deprecated.
    public UnlimitedWindows startOn(final long startMs) throws IllegalArgumentException;
    public Map<Long, UnlimitedWindow> windowsFor(final long timestamp);
	public long size();
	public long maintainMs();

	//New methods.
    public UnlimitedWindows startOn(final Instant start) throws IllegalArgumentException;
    public Map<Long, UnlimitedWindow> windowsFor(final Instant timestamp);
	public Duration size();
	public Duration maintain();
}

ProcessorContext {
    //Existing method. Will be deprecated.
    Cancellable schedule(final long intervalMs,
                         final PunctuationType type,
                         final Punctuator callback);

	//New method.
    Cancellable schedule(final Duration interval,
                         final PunctuationType type,
                         final Punctuator callback);
}

ReadOnlyWindowStore<K, V> {
    //Existing methods. Will be deprecated.
    WindowStoreIterator<V> fetch(K key, long timeFrom, long timeTo);
    KeyValueIterator<Windowed<K>, V> fetch(K from, K to, long timeFrom, long timeTo);
    KeyValueIterator<Windowed<K>, V> fetchAll(long timeFrom, long timeTo);

	//New methods.
    WindowStoreIterator<V> fetch(K key, Instant from, Duration duration);
    KeyValueIterator<Windowed<K>, V> fetch(K from, K to, Instant from, Duration duration);
    KeyValueIterator<Windowed<K>, V> fetchAll(Instant from, Duration duration);
}

SessionBytesStoreSupplier {
    //Existing methods. Will be deprecated.
    long segmentIntervalMs();
    long retentionPeriod();

    //New methods. 
    Duration segmentInterval();
    Duration retentionPeriod();
}

SessionStore {
	//Existing methods. Will be deprecated.
	KeyValueIterator<Windowed<K>, AGG> findSessions(final K key, long earliestSessionEndTime, final long latestSessionStartTime);
	KeyValueIterator<Windowed<K>, AGG> findSessions(final K keyFrom, final K keyTo, long earliestSessionEndTime, final long latestSessionStartTime);

	//New methods.
	KeyValueIterator<Windowed<K>, AGG> findSessions(final K key, Instant earliestSessionEnd, final Instant latestSessionStart);
	KeyValueIterator<Windowed<K>, AGG> findSessions(final K keyFrom, final K keyTo, Instant earliestSessionEnd, final Instant latestSessionStart);
}

Stores {
	//Existing methods. Will be deprecated.
	public static WindowBytesStoreSupplier persistentWindowStore(final String name,
    	                                                         final long retentionPeriod,
        	                                                     final long windowSize,
            	                                                 final boolean retainDuplicates);

	public static WindowBytesStoreSupplier persistentWindowStore(final String name,
    	                                                         final long retentionPeriod,
        	                                                     final long windowSize,
            	                                                 final boolean retainDuplicates,
                	                                             final long segmentInterval);

	public static SessionBytesStoreSupplier persistentSessionStore(final String name,
    	                                                           final long retentionPeriod);

	//New methods.
	public static WindowBytesStoreSupplier persistentWindowStore(final String name,
    	                                                         final Duration retentionPeriod,
        	                                                     final Duration windowSize,
            	                                                 final boolean retainDuplicates);

	public static WindowBytesStoreSupplier persistentWindowStore(final String name,
    	                                                         final Duration retentionPeriod,
        	                                                     final Duration windowSize,
            	                                                 final boolean retainDuplicates,
                	                                             final Duration segmentInterval);

	public static SessionBytesStoreSupplier persistentSessionStore(final String name,
    	                                                           final Duration retentionPeriod);
}

WindowBytesStoreSupplier {
    //Existing methods. Will be deprecated.
    long segmentIntervalMs();
    long windowSize();
    long retentionPeriod();

	//New methods.
    Duration segmentInterval();
    Duration windowSize();
    Duration retentionPeriod();
}

KafkaStreams {
	//Existing method. Will be deprecated.
	public synchronized boolean close(final long timeout, final TimeUnit timeUnit);

	//New method
	public synchronized boolean close(final Duration timeout)
}

StreamsMetrics {
	//Existing method. Will be deprecated.
	void recordLatency(final Sensor sensor,
    	               final long startNs,
        	           final long endNs);

	//New method.
	void recordLatency(final Sensor sensor,
    	               final Instant start,
        	           final Duration recDuration);
}