Package io.grpc.internal

Class AbstractServerStream

java.lang.Object

io.grpc.internal.AbstractStream

io.grpc.internal.AbstractServerStream

All Implemented Interfaces:

MessageFramer.Sink, ServerStream, Stream

Direct Known Subclasses:

NettyServerStream, ServletServerStream, ServletServerStream

public abstract class AbstractServerStream
extends AbstractStream
implements ServerStream, MessageFramer.Sink

Abstract base class for ServerStream implementations. Extending classes only need to implement transportState() and abstractServerStreamSink(). Must only be called from the sending application thread.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static interface	AbstractServerStream.Sink	A sink for outbound operations, separated from the stream simply to avoid name collisions/confusion.
protected static class	AbstractServerStream.TransportState	This should only be called from the transport thread (except for private interactions with AbstractServerStream).

Field Summary

Fields

Modifier and Type	Field	Description
private MessageFramer	framer
private boolean	headersSent
private boolean	outboundClosed
private StatsTraceContext	statsTraceCtx

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractServerStream(WritableBufferAllocator bufferAllocator, StatsTraceContext statsTraceCtx)

Method Summary

Modifier and Type	Method	Description
protected abstract AbstractServerStream.Sink	abstractServerStreamSink()	Sink for transport to be called to perform outbound operations.
private void	addStatusToTrailers(Metadata trailers, Status status)
void	cancel(Status status)	Tears down the stream, typically in the event of a timeout.
void	close(Status status, Metadata trailers)	Closes the stream for both reading and writing.
void	deliverFrame(WritableBuffer frame, boolean endOfStream, boolean flush, int numMessages)	Delivers a frame via the transport.
protected MessageFramer	framer()	The framer to use for sending messages.
Attributes	getAttributes()	Attributes describing stream.
java.lang.String	getAuthority()	Gets the authority this stream is addressed to.
boolean	isReady()	If true, indicates that the transport is capable of sending additional messages without requiring excessive buffering internally.
void	setDecompressor(Decompressor decompressor)	Sets the decompressor on the deframer.
void	setListener(ServerStreamListener serverStreamListener)	Sets the server stream listener.
void	setOnReadyThreshold(int numBytes)	A hint to the stream that specifies how many bytes must be queued before isReady() will return false.
StatsTraceContext	statsTraceContext()	The context for recording stats and traces for this stream.
protected abstract AbstractServerStream.TransportState	transportState()	Obtain the transport state corresponding to this stream.
void	writeHeaders(Metadata headers, boolean flush)	Writes custom metadata as headers on the response stream sent to the client.

Methods inherited from class io.grpc.internal.AbstractStream

endOfMessages, flush, onSendingBytes, optimizeForDirectExecutor, request, setCompressor, setMessageCompression, writeMessage

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.grpc.internal.ServerStream

streamId

Methods inherited from interface io.grpc.internal.Stream

flush, optimizeForDirectExecutor, request, setCompressor, setMessageCompression, writeMessage

Field Detail

framer

private final MessageFramer framer

statsTraceCtx

private final StatsTraceContext statsTraceCtx

outboundClosed

private boolean outboundClosed

headersSent

private boolean headersSent

Constructor Detail

AbstractServerStream

protected AbstractServerStream(WritableBufferAllocator bufferAllocator,
                               StatsTraceContext statsTraceCtx)

Method Detail

transportState

protected abstract AbstractServerStream.TransportState transportState()

Description copied from class: AbstractStream

Obtain the transport state corresponding to this stream. Each stream must have its own unique transport state.

Specified by:

transportState in class AbstractStream

abstractServerStreamSink

protected abstract AbstractServerStream.Sink abstractServerStreamSink()

Sink for transport to be called to perform outbound operations. Each stream must have its own unique sink.

framer

protected final MessageFramer framer()

Description copied from class: AbstractStream

The framer to use for sending messages.

Specified by:

framer in class AbstractStream

writeHeaders

public final void writeHeaders(Metadata headers,
                               boolean flush)

Description copied from interface: ServerStream

Writes custom metadata as headers on the response stream sent to the client. This method may only be called once and cannot be called after calls to Stream.writeMessage(java.io.InputStream) or ServerStream.close(io.grpc.Status, io.grpc.Metadata).

Specified by:

writeHeaders in interface ServerStream

Parameters:

headers - to send to client.

deliverFrame

public final void deliverFrame(WritableBuffer frame,
                               boolean endOfStream,
                               boolean flush,
                               int numMessages)

Description copied from interface: MessageFramer.Sink

Delivers a frame via the transport.

Specified by:

deliverFrame in interface MessageFramer.Sink

Parameters:

frame - a non-empty buffer to deliver or null if the framer is being closed and there is no data to deliver.

endOfStream - whether the frame is the last one for the GRPC stream

flush - true if more data may not be arriving soon

numMessages - the number of messages that this series of frames represents

close

public final void close(Status status,
                        Metadata trailers)

Description copied from interface: ServerStream

Closes the stream for both reading and writing. A status code of Status.Code.OK implies normal termination of the stream. Any other value implies abnormal termination.

Attempts to read from or write to the stream after closing should be ignored by implementations, and should not throw exceptions.

Specified by:

close in interface ServerStream

Parameters:

status - details of the closure

trailers - an additional block of metadata to pass to the client on stream closure.

addStatusToTrailers

private void addStatusToTrailers(Metadata trailers,
                                 Status status)

cancel

public final void cancel(Status status)

Description copied from interface: ServerStream

Tears down the stream, typically in the event of a timeout. This method may be called multiple times and from any thread.

Specified by:

cancel in interface ServerStream

isReady

public final boolean isReady()

Description copied from interface: Stream

If true, indicates that the transport is capable of sending additional messages without requiring excessive buffering internally. Otherwise, StreamListener.onReady() will be called when it turns true.

This is just a suggestion and the application is free to ignore it, however doing so may result in excessive buffering within the transport.

Specified by:

isReady in interface Stream

Overrides:

isReady in class AbstractStream

setDecompressor

public final void setDecompressor(Decompressor decompressor)

Description copied from interface: ServerStream

Sets the decompressor on the deframer. If the transport does not support compression, this may do nothing.

Specified by:

setDecompressor in interface ServerStream

Parameters:

decompressor - the decompressor to use.

getAttributes

public Attributes getAttributes()

Description copied from interface: ServerStream

Attributes describing stream. This is inherited from the transport attributes, and used as the basis of ServerCall.getAttributes().

Specified by:

getAttributes in interface ServerStream

Returns:

Attributes container

getAuthority

public java.lang.String getAuthority()

Description copied from interface: ServerStream

Gets the authority this stream is addressed to.

Specified by:

getAuthority in interface ServerStream

Returns:

the authority string. null if not available.

setListener

public final void setListener(ServerStreamListener serverStreamListener)

Description copied from interface: ServerStream

Sets the server stream listener.

Specified by:

setListener in interface ServerStream

statsTraceContext

public StatsTraceContext statsTraceContext()

Description copied from interface: ServerStream

The context for recording stats and traces for this stream.

Specified by:

statsTraceContext in interface ServerStream

setOnReadyThreshold

public void setOnReadyThreshold(int numBytes)

A hint to the stream that specifies how many bytes must be queued before isReady() will return false. A stream may ignore this property if unsupported. This may only be set before any messages are sent.

Specified by:

setOnReadyThreshold in interface ServerStream

Overrides:

setOnReadyThreshold in class AbstractStream

Parameters:

numBytes - The number of bytes that must be queued. Must be a positive integer.