core/src/main/java/com/google/net/stubby/transport/ClientStreamListener.java

/*
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 * in the documentation and/or other materials provided with the
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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package com.google.net.stubby.transport;

import com.google.net.stubby.Metadata;
import com.google.net.stubby.Status;

/** An observer of client-side stream events. */
public interface ClientStreamListener extends StreamListener {
  /**
   * Called upon receiving all header information from the remote end-point. Note that transports
   * are not required to call this method if no header information is received, this would occur
   * when a stream immediately terminates with an error and only
   * {@link #closed(com.google.net.stubby.Status, Metadata.Trailers)} is called.
   *
   * <p>This method should return quickly, as the same thread may be used to process other streams.
   *
   * @param headers the fully buffered received headers.
   */
  void headersRead(Metadata.Headers headers);

  /**
   * Called when the stream is fully closed. {@link
   * com.google.net.stubby.Status.Code#OK} is the only status code that is guaranteed
   * to have been sent from the remote server. Any other status code may have been caused by
   * abnormal stream termination. This is guaranteed to always be the final call on a listener. No
   * further callbacks will be issued.
   *
   * <p>This method should return quickly, as the same thread may be used to process other streams.
   *
   * @param status details about the remote closure
   * @param trailers trailing metadata
   */
  void closed(Status status, Metadata.Trailers trailers);
}