/*
 * 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
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - 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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 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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package org.eclipse.jgit.storage.dht;

/**
 * Key for any row that the DHT will be asked to store.
 * <p>
 * Implementations of this interface know how to encode and decode themselves
 * from a byte array format, expecting the DHT to use the byte array as the row
 * key within the database.
 * <p>
 * It is strongly encouraged to use only row keys that are valid UTF-8 strings,
 * as most DHT systems have client tools that can interact with rows using the
 * UTF-8 encoding.
 */
public interface RowKey {
	/** @return key formatted as byte array for storage in the DHT. */
	public byte[] asBytes();

	/** @return key formatted as a String for storage in the DHT. */
	public String asString();

	/** @return relatively unique hash code value for in-memory compares. */
	public int hashCode();

	/**
	 * Compare this key to another key for equality.
	 *
	 * @param other
	 *            the other key instance, may be null.
	 * @return true if these keys reference the same row.
	 */
	public boolean equals(Object other);

	/** @return pretty printable string for debugging/reporting only. */
	public String toString();
}