Package com.google.cloud.bigtable.data.v2.stub.changestream

Class ChangeStreamRecordMerger<ChangeStreamRecordT>

java.lang.Object

com.google.cloud.bigtable.data.v2.stub.changestream.ChangeStreamRecordMerger<ChangeStreamRecordT>

All Implemented Interfaces:

com.google.cloud.bigtable.gaxx.reframing.Reframer<ChangeStreamRecordT,ReadChangeStreamResponse>

@InternalApi
public class ChangeStreamRecordMerger<ChangeStreamRecordT>
extends Object
implements com.google.cloud.bigtable.gaxx.reframing.Reframer<ChangeStreamRecordT,ReadChangeStreamResponse>

An implementation of a Reframer that feeds the change stream record merging ChangeStreamStateMachine.

ReframingResponseObserver pushes ReadChangeStreamResponses into this class and pops a change stream record containing one of the following: 1) Heartbeat. 2) CloseStream. 3) ChangeStreamMutation(a representation of a fully merged logical mutation).

Example usage:

 ChangeStreamRecordMerger<ChangeStreamRecord> changeStreamRecordMerger =
     new ChangeStreamRecordMerger<>(myChangeStreamRecordAdaptor);

 while(responseIterator.hasNext()) {
   ReadChangeStreamResponse response = responseIterator.next();

   if (changeStreamRecordMerger.hasFullFrame()) {
     ChangeStreamRecord changeStreamRecord = changeStreamRecordMerger.pop();
     // Do something with change stream record.
   } else {
     changeStreamRecordMerger.push(response);
   }
 }

 if (changeStreamRecordMerger.hasPartialFrame()) {
   throw new RuntimeException("Incomplete stream");
 }

 

This class is considered an internal implementation detail and not meant to be used by applications.

Package-private for internal use.

See Also:

• for more details

Constructor Summary

Constructors

Constructor	Description
ChangeStreamRecordMerger(ChangeStreamRecordAdapter.ChangeStreamRecordBuilder<ChangeStreamRecordT> changeStreamRecordBuilder)

Method Summary

Modifier and Type	Method	Description
boolean	hasFullFrame()	Checks if there is a frame to be popped.
boolean	hasPartialFrame()	Checks if there is any incomplete data.
ChangeStreamRecordT	pop()	Returns and removes the current completed frame.
void	push(ReadChangeStreamResponse response)	Refill internal buffers with inner/upstream response.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ChangeStreamRecordMerger

public ChangeStreamRecordMerger(ChangeStreamRecordAdapter.ChangeStreamRecordBuilder<ChangeStreamRecordT> changeStreamRecordBuilder)

Method Details

push

public void push(ReadChangeStreamResponse response)

Description copied from interface: com.google.cloud.bigtable.gaxx.reframing.Reframer

Refill internal buffers with inner/upstream response. Should only be invoked if Reframer.hasFullFrame() returns false.

Specified by:

push in interface com.google.cloud.bigtable.gaxx.reframing.Reframer<ChangeStreamRecordT,ReadChangeStreamResponse>

hasFullFrame

public boolean hasFullFrame()

Description copied from interface: com.google.cloud.bigtable.gaxx.reframing.Reframer

Checks if there is a frame to be popped.

Note that this method might update internal to buffer the next response.

Specified by:

hasFullFrame in interface com.google.cloud.bigtable.gaxx.reframing.Reframer<ChangeStreamRecordT,ReadChangeStreamResponse>

hasPartialFrame

public boolean hasPartialFrame()

Description copied from interface: com.google.cloud.bigtable.gaxx.reframing.Reframer

Checks if there is any incomplete data. Used to check if the stream closed prematurely.

Specified by:

hasPartialFrame in interface com.google.cloud.bigtable.gaxx.reframing.Reframer<ChangeStreamRecordT,ReadChangeStreamResponse>

pop

public ChangeStreamRecordT pop()

Description copied from interface: com.google.cloud.bigtable.gaxx.reframing.Reframer

Returns and removes the current completed frame. Should only be called if hasFullFrame returns true.

Specified by:

pop in interface com.google.cloud.bigtable.gaxx.reframing.Reframer<ChangeStreamRecordT,ReadChangeStreamResponse>