Intro to OOP Visibility/protection levels and constructors Friend, convert constructor, destructor Operator overloading a<=b a.

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Egbert Bryant
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1 Intro to OOP - Object and class - The sequence to define and use a class in a program - How/when to use scope resolution operator - How/when to the dot operator - Should be able to write the prototype and implementation of a simple class Visibility/protection levels and constructors - What are the visibility levels in C++? Why these levels? - When can one access public members, when can one access private members? - What is the constructor of a class? - When is the constructor executed? - What is a default constructor? - How to invoke non-default constructor? Friend, convert constructor, destructor - How to declare a friend function? - What can a friend function do? - What is the difference between a friend function and a normal function? - Is a friend function public or private? - friend function.vs. member function - What is a convert constructor, when is it called? - How to disable the implicit invocation of a conversion constructor? - What is a copy constructor and what does it do (shallow vs deep copy). - When is a copy constructor called - What does a copy constructor look like and why are the parameters passed the way they are. - How is a copy constructor declared and implemented (with deep and shallow copies). - What is a destructor? When it is called? Operator overloading - What effect does operator overloading achieve? - overload operators need to be able to implement: ==,!=, >, >=, <, <=, = - Overloading >> and << operator as friend functions - Expressions with operator form and function form: a<=b is the following using function call syntax a.operator<=(b) - Need to able to be write code for operator overloading - How is an assignment operator different from a copy constructor? (and how it differs from the copy constructor). - What does the signature for the assignment operator look like. - What does it return and why

2 The const and static keywords - Understand each of the const used in the following program. Class SomeClass { public: abc(); void show() const; // const 1 void what(); private: void print(const abc & x); // const 2 int c; const int d; // const 3 static const int f; // const 4 }; main() { const int I = 10; // const 5 const char *p; //const 6 char * const p; //const 7 } - What is a const member function? - What is a const object? - What is const member data? - What is the use of initialization list (ctor) as regarding const data members? - What is static used for? - What is a static member function s limitation? - What is a static const used for? - What is the difference between class and instance data and methods? - What the difference between a const pointer and pointer to constant data? - What is the difference between a statically allocated array and a const pointer? Composition - Be able to code with objects within objects - The order of constructor invocation for objects within objects - The use of ctor initialization list - The use of the dot operator for object within object - Use of derefencing with member selection Array of objects - Be able to use and declare array of objects - Know how to access each object element - Know how to access the public members of an object element

3 Pointers - Relationship between variable value, variable address, pointers and reference - Pointer assignment, deference - What is problem with returning a pointer to a local function variable from a function? - Pointer arithmetic - Array form and pointer form for access array elements A[100] == *(A+100) Overloading/Dynamic memory allocation - Operator overloading with different types. - Under what situation should we use dynamic allocation of memory. - How to allocate/delete an item and an array of items. - the '->' operator: M1_ptr->simplify( ) == (*M1_ptr).simplify( ); - Correct use of new/delete for single memory address and contiguous allocated memory 'this' pointer: - Know what it is all about. - Use of this in instance members - Use in assignment operator - Why can t this be used in static members? Inheritance: - Know the basics - derived vs. base - How to declare - How the is a relationship works - Why use inheritance - Be able to look at a derived class and know what it has access to. - Know the order in which constructors will run - Know how to pass parameters to base class from derived constructors. - How to specify in a derived class the parent class constructor to execute. - What constructors are provided by compiler what is the default called constructor when derived class does not specify. - Know about function overriding - Know about scoping Polymorphism: - Know how to create and use an array of pointers to a polymorphic hierarchy. - Know about pure virtual functions and abstract class. - Know dynamic casting and how to use and why to use. - Know typeid and why to use. - Know the purpose of polymorphism

4 Standard Template Library: - Know how to declare and use containers - Know how to use associative containers - Know how to use sequential containers - Know how to use adaptive containers - Know how to use container iterators - Know best practices for containers used during the semester

5 OOP Design and Implementation OOP Review Sheet The development of a successful system depends not only on the use of the appropriate methods and techniques but also on the developer s commitment to the objectives of the systems. A successful system must: 1. Satisfy the user requirements, 2. be easy to understand by the users and operators, 3. be easy to operate, 4. have a good user interface, 5. be easy to modify, 6. be expandable, 7. have adequate security controls against misuse of data, 8. handle the errors and exceptions satisfactorily, and 9. Be delivered on schedule within the budget. The object-oriented analysis (OOA) approach consists of the following steps: 1. Understanding the problem. 2. Drawing the specification of requirement of the user and the software. 3. Identifying the objects and their attributes. 4. Identifying the services that each object is expected to provide (interface). 5. Establishing inter-connections (collaborations) between the objects in terms of services required and services rendered. The object oriented design (OOD) approach may involve the following steps: 1. Review of objects created in the analysis phase. 2. Specification of class dependencies. 3. Organization of class hierarchies. 4. Design of classes. 5. Design of member functions. 6. Design of driver program. For a class to be useful, it must contain the following functions, in addition to service functions: 1. Class management functions. a. How an object is created? b. How an object is destroyed? 2. Class implementation functions. 3. What operations are performed on the data type of a class? 4. Classes access functions. How do we get information about the internal variables of the class? 5. Class utility functions. How do we handle errors?

6 6. Other issues that are to be considered are: a. What kinds of access controls are required for the base classes? b. Which function can be made virtual? c. What library classes are expected to be used in a class? d. The design of the individual classes has a major impact on the overall quality of the software/ Given below are some guidelines that should be considered while designing a class: The public interface of a class should have only functions of the class. An object of one class should not send a message directly to a member of another class. A function should be declared public only when it is required to be used by the objects of the class. A class should be dependent on as few classes as possible. Interaction between two classes must be explicit. The top class of a structure should represent the abstract model of the target concept. Five most important features, that a software developer should keep in mind while designing a system. 1. Describe why the testing of software is important. 2. What do you mean by maintenance of software? How and when it is done? 3. Who are the major players in each stage of the system development life cycle? 4. What are the limitations of the classic software development life cycle? 5. Software development process is an iterative process. Discuss. 6. Distinguish between the Water-fall model and the fountain model. 7. Distinguish between object-oriented system analysis and system design. Which of the two require more creative talents of the system developer? 8. Distinguish between the following: (a) Classification relationship and composition relationship (b) Inheritance relationship and client-server relationship. (c) Object in problem space and object in solution space. (d) Data flow diagrams and hierarchical charts. 9. Discuss the application of structured design techniques in object-oriented programming. 10. What are the critical issues that are to be considered while designing the driver program? Why? 11. What is prototyping? How does it help improve the system design?

Object Oriented Programming. Solved MCQs - Part 2

Object Oriented Programming. Solved MCQs - Part 2 Object Oriented Programming Solved MCQs - Part 2 Object Oriented Programming Solved MCQs - Part 2 It is possible to declare as a friend A member function A global function A class All of the above What