2fb2 Associated Classes - using objects of one class within another
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Associated Classes - using objects of one class within another

Wheh you're designing an object oriented class, you'll often use other objects within it. For example, you may design a Ferry object and within it use a Time object (for when it's scheduled to leave, perhaps):
  Ferry *mersey = new Ferry(new Time(17,45),14);

There's really no special syntax involved with this - so this is just a short article to remind you that, yes, you can do this, indeed you're encouraged to do so as it makes for more robust code and cleaner calling with objects being passed around within objects. You'll sometimes here the objects within being referred to as "associated objects" or perhaps "contained objects"; you need to remember that this is nothing to do with subclasses, inheritance, and polymorphism - that's a whole different way that classes can be related to other classes.

Sample - in C++, using the above line - [here].
(written 2012-07-21, updated 2012-08-11)

 
Associated topics are indexed under
C233 - C and C based languages - OO in C++ - beyond the basics
  [3979] Extended and Associated objects - what is the difference - C++ example - (2013-01-18)
  [3508] Destructor methods in C++ - a primer - (2011-11-05)
  [3251] C++ - objects that are based on other objects, saving coding and adding robustness - (2011-04-17)
  [3244] C and C++ - preprocess, compile, load, run - what each step is for - (2011-04-12)
  [3142] Private and Public - and things between - (2011-01-22)
  [3124] C++ - putting the language elements together into a program - (2011-01-08)
  [3123] C++ objects - some short, single file demonstrations - (2011-01-07)
  [3056] C++ - a complete example with polymorphism, and how to split it into project files - (2010-11-16)
  [2845] Objects and Inheritance in C++ - an easy start - (2010-07-01)
  [2577] Complete teaching example - C++, inheritance, polymorphism - (2010-01-15)
  [1819] Calling base class constructors - (2008-10-03)
  [1674] What a lot of files! (C++ / Polymorphism demo) - (2008-06-12)
  [1572] C - structs and unions, C++ classes and polymorphism - (2008-03-13)
  [1217] What are factory and singleton classes? - (2007-06-04)
  [925] C++ - just beyond the basics. More you can do - (2006-11-14)
  [831] Comparison of Object Oriented Philosophy - Python, Java, C++, Perl - (2006-08-13)
  [801] Simple polymorphism example - C++ - (2006-07-14)
  [798] References and Pointers in C++ - (2006-07-10)


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