From de0fdbc1ee7f233e9ae363c7162171135d3b7403 Mon Sep 17 00:00:00 2001 From: mingmxu Date: Sat, 29 Apr 2017 18:51:21 -0700 Subject: [PATCH] update JavaDoc for BoundedWindow update JavaDoc rephrase JavaDoc. --- .../sdk/transforms/windowing/BoundedWindow.java | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/windowing/BoundedWindow.java b/sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/windowing/BoundedWindow.java index 74223b586715..506753dc4f77 100644 --- a/sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/windowing/BoundedWindow.java +++ b/sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/windowing/BoundedWindow.java @@ -21,11 +21,15 @@ import org.joda.time.Instant; /** - * A {@code BoundedWindow} represents a finite grouping of elements, with an - * upper bound (larger timestamps represent more recent data) on the timestamps - * of elements that can be placed in the window. This finiteness means that for - * every window, at some point in time, all data for that window will have - * arrived and can be processed together. + * A {@code BoundedWindow} represents window information assigned to data elements. + * + *

It has one method {@link #maxTimestamp()} to define an upper bound(included) of element + * timestamp. Elements within the timestamp range are placed in this window. + * Technically a window may not have a lower bound. Upper bound is mandatory as watermark, + * which also controls discarding data and expiring the window, is based on event timestamp. + * + *

At some point in time, usually when watermark passes, + * all data with the same window will arrive and can be processed together. * *

Windows must also implement {@link Object#equals} and * {@link Object#hashCode} such that windows that are logically equal will