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 4:03:17 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

program for decode the encoded numbering format into message

A: No. (Excluding if you have an old compiler, you might have to force the new operator to throw an exception if it runs out of memory.) This turns out to be a real pain to alwa

Using the Constructor There are basically three ways of creating and initializing the object. The first way to call the constructor is explicitly as :

A palindrome is a string that reads the same from both the ends. Given a string S convert it to a palindrome by doing character replacement. Your task is to convert S to palindrome

What is a newline escape sequence? - A newline escape sequence is signified by the \n character. - It is used to insert a new line whereas displaying the output data. - T

Sine function computation

In this problem you are given a board in which some of the elements are placed as shown in diagram below. Each element represents a color. Fill the other elements in the board, suc

Explain zero based addressing. - Array subscripts always start at zero. - These subscript values are used to identify elements in the array. - As subscripts start at 0, a

A:  it is containing and hiding Information regarding an object, like internal data structures and code. It isolates the internal complication of an object's operation from the res