bufferheap.java

实现数据库的storage manager 功能

/*
 * Copyright (c) 2000-2004, Rickard C鰏ter, Martin Svensson
 * 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, 
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 * and/or other materials provided with the distribution. 
 * Neither the name of SICS nor the names of its contributors 
 * may be used to endorse or promote products derived from this software 
 * without specific prior written permission. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
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package com.mellowtech.disc.sort;


/**
 * Defines methods for heaps that operates on byte buffers need to support.
 * Heaps that implement this interface should use some sort of byte buffer that
 * stores the actual data.
 *
 * @author Martin Svensson
 * @version 1.0
 */
public interface BufferHeap{
  
  /**
   * Insert a new offset into the heap.
   * @param c offset
   * @exception Exception if an error occurs
   */
  public void insert(int c) throws Exception;

  /**
   * Detete and return the offset of the smallest object in this heap
   * @return offset
   */
  public int delete();

  /**
   * Return the offset of the smallest object in this heap.
   * @return offset
   */
  public int get();
  
}