/*

 * Copyright 2001-2005 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

// A FreeBlockDictionary is an abstract superclass that will allow

// a number of alternative implementations in the future.

class FreeBlockDictionary: public CHeapObj {

 public:

  enum Dither {

    atLeast,

    exactly,

    roughly

  };

  enum DictionaryChoice {

    dictionaryBinaryTree = 0,

    dictionarySplayTree  = 1,

    dictionarySkipList   = 2

  };

 private:

  NOT_PRODUCT(Mutex* _lock;)

 public:

  virtual void       removeChunk(FreeChunk* fc) = 0;

  virtual FreeChunk* getChunk(size_t size, Dither dither = atLeast) = 0;

  virtual void       returnChunk(FreeChunk* chunk) = 0;

  virtual size_t     totalChunkSize(debug_only(const Mutex* lock)) const = 0;

  virtual size_t     maxChunkSize()   const = 0;

  virtual size_t     minSize()        const = 0;

  // Reset the dictionary to the initial conditions for a single

  // block.

  virtual void       reset(HeapWord* addr, size_t size) = 0;

  virtual void       reset() = 0;

  virtual void       dictCensusUpdate(size_t size, bool split, bool birth) = 0;

  virtual bool       coalDictOverPopulated(size_t size) = 0;

  virtual void       beginSweepDictCensus(double coalSurplusPercent,

                       float sweep_current, float sweep_ewstimate) = 0;

  virtual void       endSweepDictCensus(double splitSurplusPercent) = 0;

  virtual FreeChunk* findLargestDict() const = 0;

  // verify that the given chunk is in the dictionary.

  virtual bool verifyChunkInFreeLists(FreeChunk* tc) const = 0;

  // Sigma_{all_free_blocks} (block_size^2)

  virtual double sum_of_squared_block_sizes() const = 0;

  virtual FreeChunk* find_chunk_ends_at(HeapWord* target) const = 0;

  virtual void inc_totalSize(size_t v) = 0;

  virtual void dec_totalSize(size_t v) = 0;

  NOT_PRODUCT (

    virtual size_t   sumDictReturnedBytes() = 0;

    virtual void     initializeDictReturnedBytes() = 0;

    virtual size_t   totalCount() = 0;

  )

  virtual void       reportStatistics() const {

    gclog_or_tty->print("No statistics available");

  }

  virtual void       printDictCensus() const = 0;

  virtual void       verify()         const = 0;

  Mutex* par_lock()                const PRODUCT_RETURN0;

  void   set_par_lock(Mutex* lock)       PRODUCT_RETURN;

  void   verify_par_locked()       const PRODUCT_RETURN;

};