Quadcap Embeddable Database

com/quadcap/sql/index/BIndex.java

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package com.quadcap.sql.index;

/* Copyright 1997 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.io.IOException;
import java.util.Enumeration;

/**
 * An index is simply a map, with byte arrays as keys.
 *
 * @author Stan Bailes
 */
public interface BIndex {
    /**
     * Return this index's comparator
     */
    public Comparator getComparator();

    /**
     * Delete this index
     */
    public void free() throws IOException;

    /**
     * Get the data bytes for the specified key.  If the key is found, return
     * the length of the data portion and place as many bytes as will fit in the
     * data array.  If the key isn't found, return -1.
     */
    public int get(byte[] key, int len, byte[] data) throws IOException;

    /**
     * Delete the specified key.  Return true if the key was deleted.
     */
    public boolean delete(byte[] key) throws IOException;

    /**
     * Add a new key.  If the index is a UNIQUE index, then
     * the new key/data pair will only be added if the key does not already
     * exist, otherwise, insert will do nothing and return <b>false</b>
     * The existing value must not exist or an IOException will be thrown.
     * Otherwise, the new key/data pair is added regardless.
     */
    public void insert(byte[] key, int klen,
                          byte[] data, int off, int len) throws IOException;

    /**
     * Update the data value for an existing key.  This only works for
     * UNIQUE indexes, and only if the specified key already exists.
     *
     * @exception IOException may be thrown.
     */
    public void update(byte[] key, int klen,
                       byte[] data, int off, int len) throws IOException;

    /**
     * Set the key/data pair, replacing any any value it may present in
     * a unique index, inserting a new values, whatever.  Return
     * true if the key already existed before this operation.
     */
    public boolean set(byte[] key, int klen,
                       byte[] data, int off, int len) throws IOException;

    /**
     * Obtain a cursor for most wondrously manipulating this index.
     */
    public BCursor getCursor(boolean skipSetup) throws IOException;

//      /**
//       * Close this index
//       */
//      public void close() throws IOException;
}