source: XMLIO_V2/external/include/Poco/HashSet.h @ 80

//
// HashSet.h
//
// $Id: //poco/1.3/Foundation/include/Poco/HashSet.h#1 $
//
// Library: Foundation
// Package: Hashing
// Module:  HashSet
//
// Definition of the HashSet class.
//
// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
// 
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//


#ifndef Foundation_HashSet_INCLUDED
#define Foundation_HashSet_INCLUDED


#include "Poco/Foundation.h"
#include "Poco/LinearHashTable.h"


namespace Poco {


template <class Value, class HashFunc = Hash<Value> >
class HashSet
        /// This class implements a set using a LinearHashTable.
        ///
        /// A HashSet can be used just like a std::set.
{
public:
        typedef Value        ValueType;
        typedef Value&       Reference;
        typedef const Value& ConstReference;
        typedef Value*       Pointer;
        typedef const Value* ConstPointer;
        typedef HashFunc     Hash;
        
        typedef LinearHashTable<ValueType, Hash> HashTable;
        
        typedef typename HashTable::Iterator      Iterator;
        typedef typename HashTable::ConstIterator ConstIterator;

        HashSet()
                /// Creates an empty HashSet.
        {
        }

        HashSet(std::size_t initialReserve): 
                _table(initialReserve)
                /// Creates the HashSet, using the given initialReserve.
        {
        }
        
        HashSet(const HashSet& set):
                _table(set._table)
                /// Creates the HashSet by copying another one.
        {
        }
        
        ~HashSet()
                /// Destroys the HashSet.
        {
        }
        
        HashSet& operator = (const HashSet& table)
                /// Assigns another HashSet.
        {
                HashSet tmp(table);
                swap(tmp);
                return *this;
        }
        
        void swap(HashSet& set)
                /// Swaps the HashSet with another one.
        {
                _table.swap(set._table);
        }
        
        ConstIterator begin() const
                /// Returns an iterator pointing to the first entry, if one exists.
        {
                return _table.begin();
        }
        
        ConstIterator end() const
                /// Returns an iterator pointing to the end of the table.
        {
                return _table.end();
        }
        
        Iterator begin()
                /// Returns an iterator pointing to the first entry, if one exists.
        {
                return _table.begin();
        }
        
        Iterator end()
                /// Returns an iterator pointing to the end of the table.
        {
                return _table.end();
        }
                
        ConstIterator find(const ValueType& value) const
                /// Finds an entry in the table.
        {
                return _table.find(value);
        }

        Iterator find(const ValueType& value)
                /// Finds an entry in the table.
        {
                return _table.find(value);
        }
        
        std::size_t count(const ValueType& value) const
                /// Returns the number of elements with the given
                /// value, with is either 1 or 0.
        {
                return _table.count(value);
        }
        
        std::pair<Iterator, bool> insert(const ValueType& value)
                /// Inserts an element into the set.
                ///
                /// If the element already exists in the set,
                /// a pair(iterator, false) with iterator pointing to the 
                /// existing element is returned.
                /// Otherwise, the element is inserted an a 
                /// pair(iterator, true) with iterator
                /// pointing to the new element is returned.
        {
                return _table.insert(value);
        }
        
        void erase(Iterator it)
                /// Erases the element pointed to by it.
        {
                _table.erase(it);
        }
        
        void erase(const ValueType& value)
                /// Erases the element with the given value, if it exists.
        {
                _table.erase(value);
        }
        
        void clear()
                /// Erases all elements.
        {
                _table.clear();
        }
        
        std::size_t size() const
                /// Returns the number of elements in the table.
        {
                return _table.size();
        }
        
        bool empty() const
                /// Returns true iff the table is empty.
        {
                return _table.empty();
        }

private:
        HashTable _table;
};


} // namespace Poco


#endif // Foundation_HashSet_INCLUDED