public interface class Window {
	//New methods.
	Instant startTime();
	Instant endTime();
}

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

	//Existing method. Will be removed.
	JoinWindows grace(final long millisAfterWindowEnd);

    //New methods.
    static JoinWindows of(final Duration timeDifference) throws IllegalArgumentException;
    JoinWindows before(final Duration timeDifference) throws IllegalArgumentException;
    JoinWindows after(final Duration timeDifference) throws IllegalArgumentException;
	JoinWindows grace(final Duration afterWindowEnd) throws IllegalArgumentException;
}

Materialized {
	//Existing method. Will be removed.
	Materialized<K, V, S> withRetention(final long retentionMs);

	//New method.
	Materialized<K, V, S> withRetention(final Duration retention) throws IllegalArgumentException;
}

SessionWindows {
	//Existing methods. Will be deprecated.
    static SessionWindows with(final long inactivityGapMs);

	//Existing methods. Will be removed.
	SessionWindows grace(final long millisAfterWindowEnd);

	//New methods.
    static SessionWindows with(final Duration inactivityGap) throws IllegalArgumentException;
	SessionWindows grace(final Duration afterWindowEnd) throws IllegalArgumentException;
}

TimeWindows {
	//Existing methods. Will be deprecated.
	static TimeWindows of(final long sizeMs) throws IllegalArgumentException;
	TimeWindows advanceBy(final long advanceMs);

	//Existing method. Will be removed.
	TimeWindows grace(final long millisAfterWindowEnd);

	//New methods.
	static TimeWindows of(final Duration size) throws IllegalArgumentException;
	TimeWindows advanceBy(final Duration advance);
	TimeWindows grace(final Duration afterWindowEnd);
}

UnlimitedWindows {
	//Existing methods. Will be deprecated.
    UnlimitedWindows startOn(final long startMs) throws IllegalArgumentException;

	//New methods.
    UnlimitedWindows startOn(final Instant start) throws IllegalArgumentException;
}

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) throws IllegalArgumentException;
}


ReadOnlyWindowStore<K, V> {
    //ExistingDeprecated methods.
    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.
	//This changed after initial KIP voting based on [PR discussion](https://github.com/apache/kafka/pull/5682#discussion_r222494244)
    WindowStoreIterator<V> fetch(K key, LocalDateTimeInstant from, DurationInstant durationto) throws IllegalArgumentException;

    KeyValueIterator<Windowed<K>, V> fetch(K from, K to, LocalDateTimeInstant from, DurationInstant durationto) throws IllegalArgumentException;

    KeyValueIterator<Windowed<K>, V> fetchAll(LocalDateTimeInstant from, DurationInstant durationto) throws IllegalArgumentException;
}


SessionBytesStoreSupplierWindowStore {
	//New methods with default implementation that checks arguments and pass it to existing //Existingfetch methods.
    longWindowStoreIterator<V> segmentIntervalMs();

   fetch(K key, long timeFrom, long retentionPeriod();


    //New methods.
    Duration segmentInterval();

    Duration retentionPeriod();

}


WindowBytesStoreSupplier {
    timeTo) throws IllegalArgumentException;
    KeyValueIterator<Windowed<K>, V> fetch(K from, K to, long timeFrom, long timeTo) throws IllegalArgumentException;
    KeyValueIterator<Windowed<K>, V> fetchAll(long timeFrom, long timeTo) throws IllegalArgumentException;
}

Stores {
	//Existing methods.
 Will be deprecated.
	static longWindowBytesStoreSupplier segmentIntervalMs();

persistentWindowStore(final String name,
    	               long windowSize();

    long retentionPeriod();


	//New methods.
    Duration segmentInterval();

    Duration windowSize();

    Duration retentionPeriod();
}


JoinWindows {
    //Existing methods.
    public static JoinWindows of(final long timeDifferenceMs) throws IllegalArgumentException;


retentionPeriodMs,
        	                        public JoinWindows before(final long timeDifferenceMs) throws IllegalArgumentException;

    public JoinWindows after(final long timeDifferenceMs) throws IllegalArgumentException;


    public JoinWindows until(final long durationMs)windowSizeMs,
 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;

    publicfinal Durationboolean maintain(retainDuplicates);
}


SessionWindows {
	//Existing methods.
    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();
}


TimeWindows {
	//Exising methods.
	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();


This method added after KIP voting. Based on John Roesler comment(https://github.com/apache/kafka/pull/5682#discussion_r221472187)
	static SessionBytesStoreSupplier persistentSessionStore(final String name,
                                                               final long retentionPeriod);

	static WindowBytesStoreSupplier persistentWindowStore(final String name,
                                                          final long retentionPeriodMs,
                                                          final long windowSizeMs,
                                                          final boolean retainDuplicates,
                                                          final long segmentIntervalMs);

	//New methods.
	public static TimeWindowsWindowBytesStoreSupplier ofpersistentWindowStore(final String name,
 Duration size) throws IllegalArgumentException;

	public TimeWindows advanceBy(	                                                  final Duration advance);

	public Map<Long, TimeWindow> windowsFor(LocalDateTime timestamp);


retentionPeriod,
        	                                              publicfinal Duration size();

windowSize,
                                                        public TimeWindows until(final Durationboolean durationretainDuplicates) throws IllegalArgumentException;

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


WindowsKafkaStreams {
	//Existing methods method. Will be deprecated.
	public synchronized Windows<W>boolean untilclose(final long durationMs)timeout, throws IllegalArgumentException;


	public long maintainMs();


	public abstract long size(final TimeUnit timeUnit);


	//New methods.method
	public synchronized Windows<W>boolean untilclose(final Duration durationtimeout) throws IllegalArgumentException;

	public Duration maintain();

	public abstract Duration size();
}}