Question

Suppose that you are defining an ADT class and that you then use this class in a program. You want to separate the class and program parts into separate files as described in this chapter. Specify whether each of the following should be placed in the interface file, implementation file, or application file: a. The class definition b. The declaration for a function that is to serve as an ADT operation, but that is neither a member nor a friend of the class c. The declaration for an overloaded operator that is to serve as an ADT operation, but that is neither a member nor a friend of the class d. The definition for a function that is to serve as an ADT operation, but that is neither a member nor a friend of the class e. The definition for a friend function that is to serve as an ADT operation f. The definition for a member function g. The definition for an overloaded operator that is to serve as an ADT operation, but that is neither a member nor a friend of the class h. The definition for an overloaded operator that is to serve as an ADT operation and that is a friend of the class i. The main part of your program

Short answer

Element: - a. The class definition --> Interface file - b. The declaration for a function that is to serve as an ADT operation, but that is neither a member nor a friend of the class --> Interface file - c. The declaration for an overloaded operator that is to serve as an ADT operation, but that is neither a member nor a friend of the class --> Interface file - d. The definition for a function that is to serve as an ADT operation, but that is neither a member nor a friend of the class -> Implementation file - e. The definition for a friend function that is to serve as an ADT operation --> Implementation file - f. The definition for a member function --> Implementation file - g. The definition for an overloaded operator that is to serve as an ADT operation, but that is neither a member nor a friend of the class --> Implementation file - h. The definition for an overloaded operator that is to serve as an ADT operation and that is a friend of the class --> Implementation file - i. The main part of your program --> Application file

Step-by-step solution

a. The class definition

The class definition should be placed in the interface file. This is because the interface file contains the declarations of the class and its member functions, which are essential for the abstraction of the ADT.

b. The declaration for a function that is to serve as an ADT operation, but that is neither a member nor a friend of the class

This function declaration should be placed in the interface file as well. Since it's an ADT operation but not a member or friend function, it should be accessible to the users without having to delve into the implementation.

c. The declaration for an overloaded operator that is to serve as an ADT operation, but that is neither a member nor a friend of the class

The declaration for this overloaded operator should also be placed in the interface file since it's going to serve as an ADT operation and will be used by the users.

d. The definition for a function that is to serve as an ADT operation, but that is neither a member nor a friend of the class

The definition of this function should be placed in the implementation file. This file contains the definitions of the functions that implement the behavior of the ADT, without revealing their specifics to the users.

e. The definition for a friend function that is to serve as an ADT operation

The definition for this friend function should be placed in the implementation file. Even though it's a friend function, it's still part of the ADT behavior implementation.

f. The definition for a member function

The definition for a member function should be placed in the implementation file. Member functions are part of the ADT behavior implementation, and their definitions are separated from the class declaration to maintain abstraction.

g. The definition for an overloaded operator that is to serve as an ADT operation, but that is neither a member nor a friend of the class

The definition for this overloaded operator should be placed in the implementation file, since it belongs to the implementation part of the ADT behavior.

h. The definition for an overloaded operator that is to serve as an ADT operation and that is a friend of the class

The definition for this overloaded operator should be placed in the implementation file. Despite it being a friend function, it's still part of the ADT behavior implementation.

i. The main part of your program

The main part of the program should be placed in the application file. This file is where the ADT class is utilized to perform specific tasks and is separate from the interface and implementation files to maintain a clear separation of concerns.

Key concepts

Abstract Data Type

An Abstract Data Type (ADT) is a data type that is defined by its behavior (semantics), rather than by its implementation. It is fundamental in object-oriented programming because it allows programmers to work with the type using its interface, without needing to understand its internal workings. In the world of ADTs, the operations allowed on the data are specified through the interface, thus providing abstraction and preventing misuse of data.

• Encapsulation: ADTs encapsulate data with a set of operations that are accessible via a well-defined interface.
• Independence: The implementation of an ADT can be changed without affecting the way it is used, as long as the interface remains consistent.

For example, a `List` might be an ADT with operations like `add`, `remove`, and `find`. The details about how these operations are realized internally are hidden, allowing users to utilize the list without concerning themselves with its underlying implementation.

Class Definition

In object-oriented programming, a Class Definition is where we describe the blueprint of an object. This includes attributes (data members) and functions (methods) that operate on the data. A class definition is crucial as it forms the backbone of creating an object in programming languages like C++ or Java.

• Attributes: These are the properties or fields that hold the data related to the object. They are usually defined at the top of the class.
• Methods: These are functions that define the behavior of the objects created from the class. They can manipulate object data and perform tasks.

For instance, a `Car` class might have attributes like `color` and `model` and methods such as `drive()` and `park()`. By defining a class, we set the framework for creating objects that share the same properties and behaviors.

Interface and Implementation Separation

Separating interface from implementation is a core principle in software design meant to enhance modularity and flexibility. The interface, often presented in header files in languages like C++, defines what the ADT can do, while the implementation file shows how it does it.

• Interface: Contains the declarations of functions and is accessible by the user. It does not include details on how these functions are implemented.
• Implementation: This part contains the definitions of the functions declared in the interface. This is where the actual logic resides.

The primary benefit of separating interfaces and implementations is abstraction. Users interact with the interface and can replace the implementation without affecting the interface, which promotes reuse and easy modification.

Friend Functions

Friend functions are a unique feature in object-oriented languages like C++ that allow non-member functions to access private and protected members of a class. This can be beneficial when a function needs to operate on two different classes, having access to the private data of both.

• Flexibility: Friend functions allow for operations that cannot easily be performed within a class itself.
• Access: Despite not being class members, friend functions have access to private and protected class members, bridging between internal and external access needs.

To declare a friend function, include it in the class definition with the `friend` keyword. This grant allows specific functions to bypass standard access controls, but should be used sparingly to maintain encapsulation integrity.

Overloaded Operators

Operator overloading is a feature in many object-oriented programming languages that allows programmers to redefine how standard operators work with user-defined types. This technique adds intuitive operation capability on custom types, like arithmetic operations on complex numbers.

• Intuitive Syntax: Overloading allows operators to work with objects just as they do with fundamental data types, making code more readable.
• Flexibility: It enables the same operator to have different behaviors based on operand types, without changing the operator's original syntax.

For example, you might overload the `+` operator in a `Vector` class to enable adding two vectors together. Operator overloading should be used wisely to ensure it enhances readability and aligns with expected behaviors.