IOByteArrayMap.java

/*
 * Distributed as part of mchange-commons-java 0.2.11
 *
 * Copyright (C) 2015 Machinery For Change, Inc.
 *
 * Author: Steve Waldman <swaldman@mchange.com>
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of EITHER:
 *
 *     1) The GNU Lesser General Public License (LGPL), version 2.1, as 
 *        published by the Free Software Foundation
 *
 * OR
 *
 *     2) The Eclipse Public License (EPL), version 1.0
 *
 * You may choose which license to accept if you wish to redistribute
 * or modify this work. You may offer derivatives of this work
 * under the license you have chosen, or you may provide the same
 * choice of license which you have been offered here.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * You should have received copies of both LGPL v2.1 and EPL v1.0
 * along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
 * If not, the text of these licenses are currently available at
 *
 * LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 *  EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php 
 * 
 */

package com.mchange.io;

import java.io.*;

/**
 * A map of byte[] to byte[] that may be disk or network bound.
 * This interface is not intended to be expressed by implementations
 * supporting duplicate keys.
 */
public interface IOByteArrayMap
{
  /**
   *  Gets the byte array associated with key, or none if
   *  this key is not present.
   */
  public byte[] get(byte[] key) throws IOException;

  /**
   *  Associates the byte[] key with the byte[] value in 
   *  the hash. If key is already present in the map, the
   *  old value associated with it is replaced by <TT>value</TT>.
   */
  public void put(byte[] key, byte[] value) throws IOException;

  /**
   *  Associates the byte[] key with the byte[] value in 
   *  the hash. Fails (and returns false) if key is
   *  already present in the map.
   */
  public boolean putNoReplace(byte[] key, byte[] value) throws IOException;

  /**
   *  Removes the key, value pair whose key is the argument. 
   */
  public boolean remove(byte[] key) throws IOException; 

  /**
   *  Returns true iff <TT>key</TT> is present.
   */
  public boolean containsKey(byte[] key) throws IOException;

  /**
   *  Returns a list of all keys in the hash, provided no inserts
   *  or deletes are made while the Enumeration is untraversed.
   *  If inserts or deletes are made. the behavior is undefined. 
   */
  public IOByteArrayEnumeration keys() throws IOException;
}