Book : UML Distilled By Martin Fowler PG: 82 Topic: Multiple and Dynamic Classification (para 2) In single classification, an object belongs to a single type, which may inherit from supertypes. In Multiple classification , an object may be described by several types that are not necessarily connected by inheritance. What does Fowler meant by "may inherit from supertypes", and "not necessarily connected by inheritance". what else can an object be described by, is Fowler talking about compostion. This topic agitated me and my fellows a lot. Can any one describe this complete topic in detail.
Hello, I am sorry this is not a direct reply to your question, though i would like to add that Java is a strictly typed language where every instacne is of some type where as smalltalk is not (what i gathered by studying design patterns by gamma). That means complier will not check the type of object before assigning it to any variable. (We do have same thing in java script too) this is multiple classification (Shouldnt it be no classification ). whether my understanding of single & multiple classification is correct I would like others to comments, also why modern languages are not supporting single static classification insted of dynamic multiple classification. Fowler has suggested some ways to implement dynamic classification(i.e. at run time) in lang. like c++ can any one explain how.
Joined: Jul 10, 2001
pls read the following lines in the II para " also why modern languages are not supporting single static classification insted of dynamic multiple classification. " as "also why modern languages are supporting single static classification & not dynamic multiple classification."
Joined: Aug 06, 2001
Hello, Thanks Deepak But there is still a confusion, In Java every instance is of type Object i.e basically All objects are inhertited from Object Class. This shows inheritance; what else can an object be 'typed' by?? Still my question is the same.. if can u pls elaborate this?? ""What does Fowler meant by "may inherit from supertypes", and "not necessarily connected by inheritance"."" ppl flying high jets do comment about this.