io.grpc.internal.Stream Maven / Gradle / Ivy
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package io.grpc.internal;
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 to
* {@link StreamListener#messageRead(java.io.InputStream)}. No additional messages will be
* delivered.
*
* @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.
*
*
* When the write is "accepted" by the transport, the given callback (if provided) will be called.
* The definition of what it means to be "accepted" is up to the transport implementation, but
* this is a general indication that the transport is capable of handling more out-bound data on
* the stream. If the stream/connection is closed for any reason before the write could be
* accepted, the callback will never be invoked.
*
* @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. This event 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();
}