org.eclipse.jgit.storage.dht/src/org/eclipse/jgit/storage/dht/RowKey.java

/*
 * Copyright (C) 2011, Google Inc.
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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();
}