/*
 * Copyright (C) 2011, Google Inc.
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
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 * - Redistributions of source code must retain the above copyright
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 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
 *
 * - Neither the name of the Eclipse Foundation, Inc. nor the
 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
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package org.eclipse.jgit.storage.dht;

/**
 * Extension of {@link AsyncCallback} supporting partial results.
 * <p>
 * Instead of buffering all results for {@link #onSuccess(Object)}, the storage
 * provider may choose to offer some results earlier by invoking the
 * {@link #onPartialResult(Object)} method declared in this interface.
 * <p>
 * If any results were delivered early to {@link #onPartialResult(Object)} then
 * {@link #onSuccess(Object)} is invoked with {@code null} when all results have
 * been supplied and no more remain to be delivered.
 * <p>
 * If an error occurs, {@link #onFailure(DhtException)} will be invoked,
 * potentially after one or more {@link #onPartialResult(Object)} notifications
 * were already made. In an error condition, {@link #onSuccess(Object)} will not
 * be invoked.
 *
 * @param <T>
 *            type of object returned from the operation on success.
 */
public interface StreamingCallback<T> extends AsyncCallback<T> {
	/**
	 * Receives partial results from the operation.
	 *
	 * @param result
	 *            the result value from the operation.
	 */
	public void onPartialResult(T result);
}