io.grpc.internal.Stream Maven / Gradle / Ivy
/*
* Copyright 2014, gRPC Authors All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.grpc.internal;
import io.grpc.Compressor;
import java.io.InputStream;
/**
* A single stream of communication between two end-points within a transport.
*
* An implementation doesn't need to be thread-safe. All methods are expected to execute quickly.
*/
public interface Stream {
/**
* Requests up to the given number of messages from the call to be delivered via
* {@link StreamListener#messagesAvailable(StreamListener.MessageProducer)}. No additional
* messages will be delivered. If the stream has a {@code start()} method, it must be called
* before requesting messages.
*
* @param numMessages the requested number of messages to be delivered to the listener.
*/
void request(int numMessages);
/**
* Writes a message payload to the remote end-point. The bytes from the stream are immediately
* read by the Transport. Where possible callers should use streams that are
* {@link io.grpc.KnownLength} to improve efficiency. This method will always return immediately
* and will not wait for the write to complete. If the stream has a {@code start()} method, it
* must be called before writing any messages.
*
*
It is recommended that the caller consult {@link #isReady()} before calling this method to
* avoid excessive buffering in the transport.
*
* @param message stream containing the serialized message to be sent
*/
void writeMessage(InputStream message);
/**
* Flushes any internally buffered messages to the remote end-point.
*/
void flush();
/**
* If {@code true}, indicates that the transport is capable of sending additional messages without
* requiring excessive buffering internally. Otherwise, {@link StreamListener#onReady()} will be
* called when it turns {@code 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.
*/
boolean isReady();
/**
* Sets the compressor on the framer.
*
* @param compressor the compressor to use
*/
void setCompressor(Compressor compressor);
/**
* Enables per-message compression, if an encoding type has been negotiated. If no message
* encoding has been negotiated, this is a no-op. By default per-message compression is enabled,
* but may not have any effect if compression is not enabled on the call.
*/
void setMessageCompression(boolean enable);
}