/**************************************************************
 * 
 * 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
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 *************************************************************/



#ifndef _SALHELPER_FUTURE_HXX_
#define _SALHELPER_FUTURE_HXX_

#include <sal/types.h>
#include <osl/diagnose.h>
#include <osl/conditn.hxx>
#include <salhelper/refobj.hxx>

namespace salhelper
{

//----------------------------------------------------------------------------

#ifndef SALHELPER_COPYCTOR_API
#define SALHELPER_COPYCTOR_API(C) C (const C&); C& operator= (const C&)
#endif

//----------------------------------------------------------------------------

template<class value_type>
class FutureValue : protected osl::Condition
{
	/** Representation.
	 */
	value_type m_aValue;

	/** Not implemented.
	 */
	SALHELPER_COPYCTOR_API(FutureValue<value_type>);

public:
	inline FutureValue (const value_type& value = value_type()) SAL_THROW(())
		: m_aValue (value)
	{
		Condition::reset();
	}

	inline ~FutureValue() SAL_THROW(())
	{}

	inline sal_Bool is() const SAL_THROW(())
	{
		return const_cast<FutureValue*>(this)->check();
	}

	inline void set (const value_type& value) SAL_THROW(())
	{
		m_aValue = value;
		Condition::set();
	}

	inline value_type& get() SAL_THROW(())
	{
		Condition::wait();
		return m_aValue;
	}
};

//----------------------------------------------------------------------------

template<class value_type>
class Future : public salhelper::ReferenceObject
{
	/** Representation.
	 */
	FutureValue<value_type> m_aValue;

	/** Not implemented.
	 */
	SALHELPER_COPYCTOR_API(Future<value_type>);

public:
	inline Future (const value_type& value = value_type()) SAL_THROW(())
		: m_aValue (value)
	{}

	inline void set (const value_type& value) SAL_THROW(())
	{
		OSL_PRECOND(!m_aValue.is(), "Future::set(): value already set");
		m_aValue.set (value);
	}

	inline value_type& get() SAL_THROW(())
	{
		return m_aValue.get();
	}
};

//----------------------------------------------------------------------------

} // namespace salhelper

#endif /* !_SALHELPER_FUTURE_HXX_ */