AOO410/main/vos/inc/vos/execabl.hxx

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 * to you under the Apache License, Version 2.0 (the
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#ifndef _VOS_EXECABL_HXX_
#define _VOS_EXECABL_HXX_

#	include <vos/types.hxx>
#	include <vos/refernce.hxx>

namespace vos
{     


/** IExecutable

	The IExecutable-interface is to be understood as wrapper around
	your application-code, which allows it to be executed asynchronously.

	Wether you want real asynchronous behaviour or just pseudo-multitasking
	depends on which kind of execution-service you use to execute your executable.

	(E.g. Threadpool/Fiberpool)

	@author  Bernd Hofner
	@version 0.1
*/

class IExecutable : public vos::IReference 
{
public:

	/** Overload to implement your functionality.
		Return True, if you want "execute()" to be called again.
	*/
	virtual sal_Bool SAL_CALL execute()= 0;


	/** If you use blocking calls within your execute-function,
		you should provide here a means to unblock cleanly.
		@Return False if you are not able to unblock the
		thread.
		
	*/
	virtual sal_Bool SAL_CALL unblock()= 0;

	/**
		STL demands this operators if you want to place
		IExecutables per value in collections.
	*/
	virtual sal_Bool SAL_CALL operator<(const IExecutable&) const= 0;
	virtual sal_Bool SAL_CALL operator>(const IExecutable&) const= 0;
	virtual sal_Bool SAL_CALL operator==(const IExecutable&) const= 0;
	virtual sal_Bool SAL_CALL operator!=(const IExecutable&) const= 0;
};


/** OExecutable
	added default impl. of IReferenceCounter 
*/
class OExecutable : public vos::IExecutable,
					public vos::OReference
					
{
public:

	virtual ~OExecutable()
	{
	}

	/*
		Since the dominance of the OReferenceCounter impl.
		of the IReferenceCounter is not granted, delegate
		the methods to this branch of the diamond-shaped
		inheritance tree.
	*/

	virtual RefCount SAL_CALL acquire()
	{
		return OReference::acquire();
	}
	virtual RefCount SAL_CALL release()
	{
		return OReference::release();
	}
	virtual RefCount SAL_CALL referenced() const
	{
		return OReference::referenced();
	}


	/** Default implementation of unblock does nothing.
	*/
	virtual sal_Bool SAL_CALL unblock() { return sal_True; }


	/**
		STL demands this operators if you want to place
		IExecutables per value in collections.
		Use a default implementation of the comparison-operators
		here without a correct semantic.
	*/
	virtual sal_Bool SAL_CALL operator<(const IExecutable&) const
	{
		return sal_False;
	}

	virtual sal_Bool SAL_CALL operator>(const IExecutable&) const
	{
		return sal_False;
	}

	virtual sal_Bool SAL_CALL operator==(const IExecutable&) const
	{
		return sal_True;
	}

	virtual sal_Bool SAL_CALL operator!=(const IExecutable&) const
	{
		return sal_False;
	}
};

}


#endif  // _VOS_EXECABL_HXX_