io.grpc

Class ForwardingServerCall<RespT>

java.lang.Object

io.grpc.ServerCall<RespT>

io.grpc.ForwardingServerCall<RespT>

Direct Known Subclasses:

ForwardingServerCall.SimpleForwardingServerCall

public abstract class ForwardingServerCall<RespT>
extends ServerCall<RespT>

A ServerCall which forwards all of it's methods to another ServerCall.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ForwardingServerCall.SimpleForwardingServerCall<RespT> A simplified version of ForwardingServerCall where subclasses can pass in a ServerCall as the delegate.

Nested classes/interfaces inherited from class io.grpc.ServerCall

ServerCall.Listener<ReqT>

Constructor Summary

Constructors

Constructor and Description
ForwardingServerCall()

Method Summary

Modifier and Type	Method and Description
void	close(Status status, Metadata trailers) Close the call with the provided status.
protected abstract ServerCall<RespT>	delegate() Returns the delegated ServerCall.
boolean	isCancelled() Returns true when the call is cancelled and the server is encouraged to abort processing to save resources, since the client will not be processing any further methods.
boolean	isReady() If true, indicates that the call is capable of sending additional messages without requiring excessive buffering internally.
void	request(int numMessages) Requests up to the given number of messages from the call to be delivered to ServerCall.Listener.onMessage(Object).
void	sendHeaders(Metadata headers) Send response header metadata prior to sending a response message.
void	sendMessage(RespT message) Send a response message.
void	setCompression(String compressor) Sets the compression algorithm for this call.
void	setMessageCompression(boolean enabled) Enables per-message compression, if an encoding type has been negotiated.

Methods inherited from class java.lang.Object

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

Constructor Detail

ForwardingServerCall

public ForwardingServerCall()

Method Detail

delegate

protected abstract ServerCall<RespT> delegate()

Returns the delegated ServerCall.

request

public void request(int numMessages)

Description copied from class: ServerCall

Requests up to the given number of messages from the call to be delivered to ServerCall.Listener.onMessage(Object). Once numMessages have been delivered no further request messages will be delivered until more messages are requested by calling this method again.

Servers use this mechanism to provide back-pressure to the client for flow-control.

This method is safe to call from multiple threads without external synchronizaton.

Specified by:

request in class ServerCall<RespT>

Parameters:

numMessages - the requested number of messages to be delivered to the listener.

sendHeaders

public void sendHeaders(Metadata headers)

Description copied from class: ServerCall

Send response header metadata prior to sending a response message. This method may only be called once and cannot be called after calls to ServerCall.sendMessage(RespT) or ServerCall.close(io.grpc.Status, io.grpc.Metadata).

Since Metadata is not thread-safe, the caller must not access headers after this point.

Specified by:

sendHeaders in class ServerCall<RespT>

Parameters:

headers - metadata to send prior to any response body.

sendMessage

public void sendMessage(RespT message)

Description copied from class: ServerCall

Send a response message. Messages are the primary form of communication associated with RPCs. Multiple response messages may exist for streaming calls.

Specified by:

sendMessage in class ServerCall<RespT>

Parameters:

message - response message.

isReady

public boolean isReady()

Description copied from class: ServerCall

If true, indicates that the call is capable of sending additional messages without requiring excessive buffering internally. This event is just a suggestion and the application is free to ignore it, however doing so may result in excessive buffering within the call.

This implementation always returns true.

Overrides:

isReady in class ServerCall<RespT>

close

public void close(Status status,
                  Metadata trailers)

Description copied from class: ServerCall

Close the call with the provided status. No further sending or receiving will occur. If Status.isOk() is false, then the call is said to have failed.

If no errors or cancellations are known to have occurred, then a ServerCall.Listener.onComplete() notification should be expected, independent of status. Otherwise ServerCall.Listener.onCancel() has been or will be called.

Since Metadata is not thread-safe, the caller must not access trailers after this point.

Specified by:

close in class ServerCall<RespT>

isCancelled

public boolean isCancelled()

Description copied from class: ServerCall

Returns true when the call is cancelled and the server is encouraged to abort processing to save resources, since the client will not be processing any further methods. Cancellations can be caused by timeouts, explicit cancel by client, network errors, and similar.

This method may safely be called concurrently from multiple threads.

Specified by:

isCancelled in class ServerCall<RespT>

setMessageCompression

@ExperimentalApi
public void setMessageCompression(boolean enabled)

Description copied from class: ServerCall

Enables per-message compression, if an encoding type has been negotiated. If no message encoding has been negotiated, this is a no-op.

Overrides:

setMessageCompression in class ServerCall<RespT>

setCompression

@ExperimentalApi
public void setCompression(String compressor)

Description copied from class: ServerCall

Sets the compression algorithm for this call. If the server does not support the compression algorithm, the call will fail. This method may only be called before ServerCall.sendHeaders(io.grpc.Metadata). The compressor to use will be looked up in the CompressorRegistry. Default gRPC servers support the "gzip" compressor.

Overrides:

setCompression in class ServerCall<RespT>

Parameters:

compressor - the name of the compressor to use.