Do friends break encapsulation?, C/C++ Programming

A: No. If they're utilized properly, they increase encapsulation.

You frequently require splitting a class in half while the two halves will have distinct numbers of instances or distinct lifetimes. In these cases, usually the two halves need direct access to each other (the two halves utilized to be in the similar class, thus you haven't enhanced the amount of code that required direct access to data structure; you've simply reshuffled the code in two classes rather than one). The safest method to implement it is to make the two halves friends of each other.

If you employ friends like just defined, you'll keep private things private. People who don't understand this frequently make naive efforts to ignore using friendship in situations such as the above, and frequently they in fact destroy encapsulation. They either employ public data (grotesque!), or they make the data accessible among the halves using public get() and set() member functions. Having a public get() & set() member function for private datum is OK only while the private datum "makes sense" from outside the class (from a user's perspective). In several cases, these get()/set() member functions are approximately as bad as public data: they hide (only) the name of the private datum, however they don't hide the existence of the private datum.

Likewise, if you employ friend functions as a syntactic variant of a class's public access functions, they don't break encapsulation any more than a member function breaks encapsulation. In other terms, a class's friends don't violate the encapsulation barrier: along the class's member functions, they are the encapsulation barrier.

 (Several people think of a friend function as something outside the class. Rather then, try thinking of a friend function as part of the class's public interface. In the class declaration a friend function doesn't violate encapsulation any more than a public member function break encapsulation: both have exactly the similar authority with respect to accessing the class's non-public parts.)

 

Posted Date: 3/20/2013 4:03:41 AM | Location : United States







Related Discussions:- Do friends break encapsulation?, Assignment Help, Ask Question on Do friends break encapsulation?, Get Answer, Expert's Help, Do friends break encapsulation? Discussions

Write discussion on Do friends break encapsulation?
Your posts are moderated
Related Questions
A: No. Syntax wise it is permitted. But then the function is no longer Inline. Since the compiler will never know how deep the recursion is at compilation time.

Program is to perform string operations: Program is to perform string operation without using in built functions using classes and object void mainmenu()    {    clrs


if one won't explicitly call the destructor of a local; then how does he handle the above situation?

Describe the “placement new" and why would I use it?

This is what I need help with. "Create a program creates an interface allowing the user to select from some other programs I have made one being a money converter and the other ca

Q: however shouldn't I always use a printOn() method instead of a friend function? A: No. The usual cause people wish to always use a printOn() method instead of  a friend fu

.Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b.

Program1: Write a program to find the factorial of a given number. The input is user given. Final output is printed out on to the screen. Program2: Write a program to gene

#question.Write a c++ program to accept and print a 1_d array