com.hazelcast.jet.pipeline

Interface WindowDefinition

All Known Implementing Classes:

SessionWindowDef, SlidingWindowDef

public interface WindowDefinition

The definition of the window for a windowed aggregation operation. The enum WindowDefinition.WindowKind enumerates the kinds of window that Jet supports. To obtain a window definition, use the factory methods provided in this interface.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	WindowDefinition.WindowKind Enumerates the kinds of window that Jet supports.

Method Summary

Modifier and Type	Method and Description
<W extends WindowDefinition> W	downcast() Returns this window definition downcast to the type determined through type inference at the call site.
WindowDefinition.WindowKind	kind() Returns what kind of window this definition describes.
static SessionWindowDef	session(long sessionTimeout) Returns a session window definition with the given parameters.
static SlidingWindowDef	sliding(long windowSize, long slideBy) Returns a sliding window definition with the given parameters.
static SlidingWindowDef	tumbling(long windowSize) Returns a tumbling window definition with the given parameters.
long	watermarkFrameSize() Returns the frameLength and offset this window definition needs.

Method Detail

kind

@Nonnull
WindowDefinition.WindowKind kind()

Returns what kind of window this definition describes.

downcast

@Nonnull
<W extends WindowDefinition> W downcast()

Returns this window definition downcast to the type determined through type inference at the call site. It will be an unchecked downcast and may fail at runtime with a ClassCastException.

Type Parameters:

W - The target type of the downcast

Returns:

this object, downcast into the inferred type

watermarkFrameSize

long watermarkFrameSize()

Returns the frameLength and offset this window definition needs.

sliding

@Nonnull
static SlidingWindowDef sliding(long windowSize,
                                         long slideBy)

Returns a sliding window definition with the given parameters.

Parameters:

windowSize - the size of the window (size of the range of the timestamps it covers)

slideBy - the size of the sliding step. Window size must be multiple of this number.

tumbling

@Nonnull
static SlidingWindowDef tumbling(long windowSize)

Returns a tumbling window definition with the given parameters. Tumbling window is a special case of sliding where the slide is equal to window size.

Parameters:

windowSize - the size of the window (size of the range of the timestamps it covers)

session

@Nonnull
static SessionWindowDef session(long sessionTimeout)

Returns a session window definition with the given parameters.

Parameters:

sessionTimeout - the exclusive upper bound on the difference between any two successive timestamps included in a window.