Apache9 commented on code in PR #6167:
URL: https://github.com/apache/hbase/pull/6167#discussion_r1759744708
##########
hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncTable.java:
##########
@@ -676,6 +676,47 @@ interface CoprocessorCallback<R> {
void onError(Throwable error);
}
+ /**
+ * Some coprocessors may support the idea of "partial results." If for some
reason a coprocessor
+ * cannot return all results for a given region in a single response, the
client side can be
+ * designed to recognize this and continuing requesting more results until
they are completely
+ * accumulated in the client.
+ * <p>
+ * It is up to a particular coprocessor implementation and its corresponding
clients to agree on
+ * what it means for results to be incomplete, how this state is
communicated, and how multiple
+ * incomplete results are accumulated together.
+ * <p>
+ * Use this callback when you want to execute a coprocessor call on a range
of regions, and that
+ * coprocessor may return incomplete results for a given region. See also
the docs for
+ * {@link CoprocessorCallback}, which all apply here to its child interface
too.
+ */
+ @InterfaceAudience.Public
+ interface PartialResultCoprocessorCallback<S, R> extends
CoprocessorCallback<R> {
+ /**
+ * Subclasses should implement this to tell AsyncTable whether the given
response is "final" or
+ * whether the AsyncTable should send another request to the coprocessor
to fetch more results
+ * from the given region. This method of fetching more results can be used
many times until
+ * there are no more results to fetch from the region.
+ * @param response The response received from the coprocessor
+ * @param region The region the response came from
+ * @return A ServiceCaller object if the response was not final and
therefore another request is
+ * required to continuing fetching results. null if no more
requests need to be sent to
+ * the region.
+ */
+ ServiceCaller<S, R> getNextCallable(R response, RegionInfo region);
+
+ /**
+ * Subclasses should implement this such that, when the above method
returns non-null, this
+ * method returns the number of milliseconds that AsyncTable should wait
before sending the next
+ * request to the given region. You can use this to create a back-off
behavior to reduce load on
+ * the RegionServer. If that's not desired, you can always return 0.
+ * @param response The response received from the coprocessor
+ * @param region The region the response came from
+ * @return The number of milliseconds to wait.
+ */
+ long getWaitIntervalMs(R response, RegionInfo region);
Review Comment:
Return a Duration?
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: issues-unsubscr...@hbase.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
