com.google.cloud.bigtable.grpc.scanner

Class ResponseQueueReader

java.lang.Object

com.google.cloud.bigtable.grpc.scanner.ResponseQueueReader

All Implemented Interfaces:

io.grpc.stub.ClientResponseObserver<com.google.bigtable.v2.ReadRowsRequest,FlatRow>, io.grpc.stub.StreamObserver<FlatRow>

@InternalApi(value="For internal usage only")
public class ResponseQueueReader
extends Object
implements io.grpc.stub.StreamObserver<FlatRow>, io.grpc.stub.ClientResponseObserver<com.google.bigtable.v2.ReadRowsRequest,FlatRow>

Manages a queue of ResultQueueEntrys of FlatRow.

For internal use only - public for technical reasons.

Constructor Summary

Constructors

Constructor and Description
ResponseQueueReader() Constructor for ResponseQueueReader.

Method Summary

Modifier and Type	Method and Description
void	addRequestResultMarker() This marker notifies getNextMergedRow() to request more results and allows for flow control based on the state of the resultQueue.
int	available() available.
void	beforeStart(io.grpc.stub.ClientCallStreamObserver<com.google.bigtable.v2.ReadRowsRequest> requestStream)
void	close()
protected com.google.cloud.bigtable.grpc.scanner.ResultQueueEntry<FlatRow>	getNext() getNext.
FlatRow	getNextMergedRow() Get the next complete FlatRow object from the response queue.
void	onCompleted()
void	onError(Throwable t)
void	onNext(FlatRow row)

Methods inherited from class java.lang.Object

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

Constructor Detail

ResponseQueueReader

public ResponseQueueReader()

Constructor for ResponseQueueReader.

Method Detail

beforeStart

public void beforeStart(io.grpc.stub.ClientCallStreamObserver<com.google.bigtable.v2.ReadRowsRequest> requestStream)

Specified by:

beforeStart in interface io.grpc.stub.ClientResponseObserver<com.google.bigtable.v2.ReadRowsRequest,FlatRow>

close

public void close()

getNextMergedRow

public FlatRow getNextMergedRow()
                         throws IOException

Get the next complete FlatRow object from the response queue.

Returns:

null if end-of-stream, otherwise a complete FlatRow.

Throws:

IOException - On errors.

getNext

protected com.google.cloud.bigtable.grpc.scanner.ResultQueueEntry<FlatRow> getNext()
                                                                            throws IOException

getNext.

Returns:

a ResultQueueEntry object.

Throws:

IOException - if any.

available

public int available()

available.

Returns:

a int.

onNext

public void onNext(FlatRow row)

Specified by:

onNext in interface io.grpc.stub.StreamObserver<FlatRow>

onError

public void onError(Throwable t)

Specified by:

onError in interface io.grpc.stub.StreamObserver<FlatRow>

onCompleted

public void onCompleted()

Specified by:

onCompleted in interface io.grpc.stub.StreamObserver<FlatRow>

addRequestResultMarker

public void addRequestResultMarker()

This marker notifies getNextMergedRow() to request more results and allows for flow control based on the state of the resultQueue. If rows are removed from the queue quickly, getNextMergedRow() will request more results. If rows are not read fast enough, then gRPC will stop fetching rows, and will wait until more rows are requested. This marker tells getNextMergedRow() to read more rows.