Title
============
Abstract Constructor

Author's name
=============
Manfred Lange

Telecom
=======
e-mail: Manfred_Lange@hp.com
phone:  49-7031-14-2795
fax:    49-7031-14-4987

Snail Mail
==========
Manfred Lange
Hewlett-Packard GmbH
European Support Technology Lab (ESTL)
Herrenberger Strasse 130
71034 Boeblingen
Germany

Abstract
========
The paper describes a typed-language specific pattern,
which implements a mechanism for creating objects given
any kind of description. Two application examples are
presented showing how to implement and use the pattern
in practice.
In general the pattern can be applied by added two
static members to the classes which take part in the
Abstract Constructor mechanism.
The pattern can be used in the following cases:
- objects within one class hierarchy tree are given,
and appropriate objects in a different class hierarchy
tree should be attached
- a stream with serialized objects is given, and the
objects should be de-serialized
- a piece of information is given and an object that
fits best should be determined and created.
The pattern has been successfully applied several times
in different projects. The current implementation is
available as a C++ template, thus allowing easy adaption
of the pattern.
The paper also describes a generic solution to the
problem of registering all constructors during startup
of an application.
The pattern is an extension of the existing virtual
constructor patterns as described by James Coplien,
Steven Berczuk and others.