Object-oriented frameworks are a particularly appealing approach towards so
ftware reuse. An object-oriented framework represents a design for a family
of applications, where variations in the application domain are tackled by
filling in the so-called hot spots. However, experience has shown that the
current object-oriented mechanisms (class inheritance and object compositi
on) are not able to elegantly support the "fill in the hot spot" idea. This
paper introduces class composition as a more productive approach towards h
ot spots, offering all of the advantages of both class inheritance and obje
ct composition but involving extra work for the framework designer. (C) 199
9 John Wiley & Sons, Inc.