io.grpc.internal

Interface ClientTransport

@ThreadSafe
public interface ClientTransport

The client-side transport encapsulating a single connection to a remote server. Allows creation of new Stream instances for communication with the server. All methods on the transport and its listener are expected to execute quickly.

start(io.grpc.internal.ClientTransport.Listener) must be the first method call to this interface and return before calling other methods.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	ClientTransport.Listener Receives notifications for the transport life-cycle events.
static interface	ClientTransport.PingCallback A callback that is invoked when the acknowledgement to a ping(io.grpc.internal.ClientTransport.PingCallback, java.util.concurrent.Executor) is received.

Method Summary

Modifier and Type	Method and Description
ClientStream	newStream(MethodDescriptor<?,?> method, Metadata.Headers headers, ClientStreamListener listener) Creates a new stream for sending messages to the remote end-point.
void	ping(ClientTransport.PingCallback callback, Executor executor) Pings the remote endpoint to verify that the transport is still active.
void	shutdown() Initiates an orderly shutdown of the transport.
void	start(ClientTransport.Listener listener) Starts transport.

Method Detail

newStream

ClientStream newStream(MethodDescriptor<?,?> method,
                       Metadata.Headers headers,
                       ClientStreamListener listener)

Creates a new stream for sending messages to the remote end-point.

This method returns immediately and does not wait for any validation of the request. If creation fails for any reason, ClientStreamListener.closed(io.grpc.Status, io.grpc.Metadata.Trailers) will be called to provide the error information. Any sent messages for this stream will be buffered until creation has completed (either successfully or unsuccessfully).

Parameters:

method - the descriptor of the remote method to be called for this stream.

headers - to send at the beginning of the call

listener - the listener for the newly created stream.

Returns:

the newly created stream.

Throws:

IllegalStateException - if the service is already stopped.

start

void start(ClientTransport.Listener listener)

Starts transport. This method may only be called once.

Implementations must not call listener from within start(io.grpc.internal.ClientTransport.Listener); implementations are expected to notify listener on a separate thread. This method should not throw any exceptions.

Parameters:

listener - non-null listener of transport events

ping

void ping(ClientTransport.PingCallback callback,
          Executor executor)

Pings the remote endpoint to verify that the transport is still active. When an acknowledgement is received, the given callback will be invoked using the given executor.

This is an optional method. Transports that do not have any mechanism by which to ping the remote endpoint may throw UnsupportedOperationException.

shutdown

void shutdown()

Initiates an orderly shutdown of the transport. Existing streams continue, but new streams will fail (once ClientTransport.Listener.transportShutdown(io.grpc.Status) callback called). This method may only be called once.