/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/



#ifndef _HASHTBL_HXX
#define _HASHTBL_HXX

// ADT hash table
//
// Invariante:
//    1. m_lElem < m_lSize
//    2. die Elemente in m_Array wurden double-hashed erzeugt
//
class HashItem;

class HashTable
{
    unsigned long m_lSize;
    unsigned long m_lElem;
    HashItem *m_pData;
    double    m_dMaxLoadFactor;
    double    m_dGrowFactor;
    bool      m_bOwner;

    unsigned long Hash(const char *cKey) const;
    unsigned long DHash(const char *cKey , unsigned long lHash) const;
    unsigned long Probe(unsigned long lPos) const;

    HashItem* FindPos(const char *cKey) const;
    void      SmartGrow();
    double    CalcLoadFactor() const;

protected:
	friend class HashTableIterator;

    virtual void OnDeleteObject(void* pObject);

    void* GetObjectAt(unsigned long lPos) const;

// Default-Werte
public:
	static double m_defMaxLoadFactor;
	static double m_defDefGrowFactor;

public:
    HashTable
	(
		unsigned long	lSize,
		bool	bOwner,
		double	dMaxLoadFactor = HashTable::m_defMaxLoadFactor /* 0.8 */,
		double	dGrowFactor = HashTable::m_defDefGrowFactor /* 2.0 */
	);

    virtual ~HashTable();

    bool  IsFull() const;
    unsigned long GetSize() const { return m_lSize; }

    void* Find   (const char *cKey ) const;
    bool  Insert (const char *cKey , void* pObject);
    void* Delete (const char *cKey);
};

// ADT hash table iterator
//
// Invariante: 0 <= m_lAt < m_aTable.GetCount()
//
class HashTableIterator
{
	unsigned long	 m_lAt;
	HashTable const& m_aTable;

    void operator =(HashTableIterator &); // not defined

	void* FindValidObject(bool bForward);

protected:
	void* GetFirst(); // Interation _ohne_ Sortierung
	void* GetNext();
	void* GetLast();
	void* GetPrev();

public:
	HashTableIterator(HashTable const&);
};

#endif // _HASHTBL_HXX