# 1. Objectives. Objectives. 13.Visual Studio Projects. C/C++ The array is an Aggregate!

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1 1 2 Objectives 1. Agregates 2. Structs 3. Introduction To Classes 4. Constructor 5. Destructor 6. Function Overloading 7. Default Arguments 8. Accessors & Mutators 9. ADT Abstract Data Types 10. Operator Overloads >, >=, <, <=,!=, ==, = 11. Partition Class -.hpp &.cpp 12. Indigenous Data & Exogenous Data 3 3 Objectives 13.Visual Studio Projects Execute Binary Outside Visual Studio Net Environment Redirecting Output To A Text File Other Files In The Debug Folder 4 4 Aggregate A Collection Of Objects Stored As One Unit! FirstName[15], LastName[20]; No[21]; float Data[10]; C/C++ The array is an Aggregate! C/C++ A array is an Aggregate in which the objects have to be of the same type! # 1

2 Aggregate A Collection Of Objects Stored As One Unit! struct FirstName[15], LastName[20]; ; One of the advantages of an aggregate is that you can pass a single argument, that represents many components, to a function. C/C++ A struct is an Aggregate in which the objects do not have to be of the same type! If you have not written a sample program which contains John; a struct, you should do so. You are responsible for it! John.No = 20; strcpy(john.firstname, John ); strcpy(john.lastname, Smith ); Set(&John, "John", "Smith", 20); 7 7 void Set ( * This, NewFirst[], NewLast, NewNo) This->No = New strcpy(this->firstname, NewFirst); void Display ( This); strcpy(this->lastname, NewLast); 8 # include <stdio.h> # include <string.h> struct ; FirstName[15], LastName[20]; Complete C/C++ Program Using A Struc void Set1 ( * This, NewFirst[], NewLast[], NewNo); void Set2 ( * This, NewFirst[], NewLast[], NewNo); void Display ( This); main() John; John.No = 20; strcpy(john.firstname, "John"); strcpy(john.lastname, "Smith"); Set1(&John, "John", "Smith", 20); Display(John); Set2(&John, "John", "Doe", 21); Display(John); return (0); void Set1 ( * This, NewFirst[], NewLast[], NewNo) This->No = New strcpy(this->firstname, NewFirst); strcpy(this->lastname, NewLast); Output No = 20 First = John Second = Smith No = 21 First = John Second = Doe void Set2 ( * This, * NewFirst, * NewLast, NewNo) (*This).No = New strcpy((*this).firstname, NewFirst); strcpy((*this).lastname, NewLast); void Display ( This) prf ("No = %d\n", This.No); prf ("First = %s\n", This.FirstName); prf ("Second = %s\n\n", This.LastName); C/C++ The struct is an Aggregate! Aggregate A Collection Of Objects Stored As One Unit! class (void); void Set ( NewNo, NewFirst[], NewLast[]); FirstName[15], LastName[20]; ; void ::Set( NewNo, NewFirst[], NewLast[]) No = New strcpy(firstname, NewFirst); strcpy(lastname, NewLast); C++ A Class is an Aggregate in which the objects do not have to be of the same type! John; John.Set(20,"John","Doe"); # 2

3 About Classes class (void); ~ (void); void Set ( NewName[], long NewNo, bool NewSex); void Display( Message[]); Name [26]; # define MALE false # define FEMALE true bool Sex; ; Class bundles both data and methods [ encapsulation] ; not so with structs. Class functions are called Methods or Member Functions [Constructor, Destructor, Set, Display]. Class data are called Data Members [ Name, No, Sex]. Each class has a public portion containing Methods & Data available to all that utilize the class. Each class has a private portion containing Methods & Data available to all that utilize the class Special Method - Constructor class (void); ~ (void); void Set ( NewName[], long NewNo, bool NewSex); void Display( Message[]); Constructor - Does all that is necessary To Create The Object void ::(void) strcpy (Name, ""); No = 0; Sex = FEMALE; Constructor Automatically called each time an object is created. main() John; John.Set("John",22,MALE); Inefficient - Assigns Data Members twice! Once in Constructor and once in Set! Multiple Constructors class Scope Operator => :: (void); ( NewName[], long NewNo, bool NewSex); ~ (void); void Set ( NewName[], long NewNo, bool NewSex); void Display( Message[]); Constructor - Does all that is necessary To Create The Object void ::(void) strcpy (Name, ""); No = 0; Sex = FEMALE; void ::( NewName[], long NewNo, bool NewSex) strcpy (Name, NewName); No = New Sex = NewSex; main() John, Sarah("Sarah", 111, FEMALE); "Function Overloading when a function will accept more than one signature. 17 Overloaded Functions - functions which will accept more than one calling signature - function overloading extends the ways in which it can be called! John, Signature => void/nothing/- "Function Overloading" Sarah("Sarah", 111, FEMALE); Signature => string,,bool Any function can be overloaded again and again as long as each variation has a unique signature. Function overloading is pretty unique to C++; it is not supported in standard C or most other languages. void Set ( NewName[], long NewNo, bool NewSex); (s,l,b) void Set ( NewName[], bool NewSex, long NewNo); (s,b,l) void Set (long NewNo, bool NewSex, NewName[]); (l,b,s) void Set (long NewNo, NewName[], bool NewSex); (l,s,b) void Set (bool NewSex, NewName[], long NewNo); (b,s,l) void Set (bool NewSex, long NewNo, NewName[]); (b,l,s) void Set ( NewName[], long NewNo); (s,l) void Set ( NewName[], bool NewSex); (s,b) void Set (long NewNo, bool NewSex); (l,b) void Set (long NewNo, NewName[]); (l,s) void Set (bool NewSex, NewName[]); (b,s) void Set (bool NewSex, long NewNo); (b,l) void Set ( NewName[]); (s) void Set (long NewNo); (l) void Set (bool NewSex); (b) 18 void Set (); # 3

4 Default Arguments can also be used to achieve function overloading. Default arguments must be in a continuous sequence from right to left! void ( NewName[] = "", long NewNo = 0, bool NewSex = FEMALE); Constructor 1 Accepts the following signatures: (s,l,b) (s,l) (b) () s1("jane", 11, FEMALE), s2("amy", 22), s3("sarah"), s4; Default Arguments Also Facilitate "Function Overloading" void Set (long NewNo, bool NewSex = FEMALE, NewName[] = ""]); Constructor 2 Accepts the following signatures: (l,b,s) (l,b) (l) s5(55, FEMALE, "Rhonda"), s6(66, MALE), s7("becky"); Note That Default Arguments are in Prototype Only! 20 Destructors class Destructor Automatically called each time an object goes out of scope. (void); ( NewName[], long NewNo, bool NewSex); ~ (void); void Set ( NewName[], long NewNo, bool NewSex); void Display( Message[]); Destructor - Does all that is necessary Destroy The Object void :: ~ (void) // puts ( Evoking Destructor ~() ); Destructor - Not Required for class, but must coded it if prototyped in class definition. "2 Objects Created Here" main() John, Sarah("Sarah", 111, FEMALE);... "2 Objects Destoyed Here" 22 When Are Destructors Really Needed? class Stack Destructor Required to prevent "Memory Leak" Stack (unsigned long NewMax = 10); ~Stack (void);... Note That Default Arguments are in Prototype Only! * Array; long Max, Top; // Initialize to -1 for Empty void Stack::Stack(unsigned long NewMax) Max = NewMax; Memory Dynamically Allocated - new Top = -1; Array = new [Max + 1]; void Stack:: ~Stack(void) Memory Dynamically De-Allocated - Returned To OS Memory Manager - delete [] Array; delete 23 When Are Destructors Really Needed? 1. Constructor allocates memory, destructor must deallocate memory 2. Constructor opens file(s), destructor might close it/them 3. Constructor uses AtoD card to turn on power to a sound system, destructor might turn it off 4. Constructor reads starting data from file, destructor might write ending data to that file 5. etc. // Application Dependent! All C++ compilers will define a default destructor, which does nothing, in the absence of a prototyped destructor. 24 T # 4

5 Mutators - Set class (void); ( NewName[], long NewNo, bool NewSex); ~ (void); void Set ( NewName[], long NewNo, bool NewSex); void Display( Message[]); Mutator- A method that changes the state of an object. void ::Set ( NewName[ ], long NewNo, bool NewSex) strcpy (Name, NewName); No = New Sex = NewSex; main() Sarah; Sarah.Set("Sarah", 111, FEMALE); Accessors - Display class (void); ( NewName[], long NewNo, bool NewSex); ~ (void); void Set ( NewName[], long NewNo, bool NewSex); void Display( Message[]); Accessor - A method that examines, but not change the state of an object void ::Display ( Message[ ]) puts (Message); prf( Name: %s\n, Name); prf( No : %ld\n, No); if (Sex = MALE) prf( Sex : Male\n ); else prf( Sex : Female\n ); main() Sarah ("Sarah", 111, FEMALE); Sarah.Display( InfoAbout Sarah ); ADT Abstract Data Type - A unique data type that is defined by the programmer! Think Abstraction! class Stack Stack(void); bool Push (InfoType NewInfo); bool Pop (InfoType & TopInfo); bool Empty (void); InfoType Array[100]; Top; ; # 5

6 // I have decided that Name is to be the Primary Character Key for this record type. bool operator == (const Key[]); bool operator > (const Key[]); bool operator >= (const Key[]); bool operator < (const Key[]); bool operator <= (const Key[]); bool operator!= (const Key[]); void operator = (const Key[]); Operators Are Overloaded In Order To Enable The Programmer To Compare A Class With a String, Numeric, or an other Object. Used For Searching & Sorting/Ordering. // I have decided that No is to be the Primary Long Integer Key for this record type. bool operator == (const long Key); bool operator > (const long Key); bool operator >= (const long Key); bool operator < (const long Key); bool operator <= (const long Key); bool operator!= (const long Key); void operator = (const long Key); // I have decided that Name is to be the Primary Key for this record type. bool operator == (const & S); bool operator > (const & S); bool operator >= (const & S); bool operator < (const & S); bool operator <= (const & S); bool operator!= (const & S); void operator = (const & S); ( NewName[] = "", long NewNo = 0, bool NewSex = FEMALE); (long NewNo, NewName[] = "", bool NewSex = FEMALE); ~ (void); void Set ( NewName[] = "", long NewNo = 0, bool NewSex = FEMALE); Name [26]; bool ex; 32 ; // operator Overloads // // operators in such a way // Purpose : Overload the that the Name becomes the // primary acter key for the Class. // // : Dr. Thomas E. Hicks Environment // Written By : Windows NT // Date : 10/25/00 Compiler : Visual C++ // bool ::operator == (const Key[]) if (strcmp(name, Key) == 0) return (true); else return (false); // operator Overloads // // operators in such a way // Purpose : Overload the that the No becomes the // primary eger key for the Class. // // : Dr. Thomas E. Hicks Environment // Written By : Windows NT // Date : 10/25/00 Compiler : Visual C++ // bool ::operator == (const long Key) if (No == Key) return (true); else return (false); John ("John", 111, MALE), Sarah ("Sarah", 222, FEMALE); if (Sarah == "Sarah") John ("John", 111, MALE), Sarah ("Sarah", 222, FEMALE); if (John == 222) // operator Overloads // // the operators in such a way that // Purpose : Overload the Name becomes the // primary key for the Class. // // : Dr. Thomas E. Hicks Environment // Written By : Windows NT // Date : 10/25/00 Compiler : Visual C++ // bool ::operator == (const & S) if (strcmp(name, S.Name) == 0) return (true); else return (false); Often Overload =, >, >=,!=, <, <=, == John ("John", 111, MALE), Sarah ("Sarah", 222, FEMALE); if (John == Sarah) # 6

7 Can Overload Other Things >>, <<, +, -, etc. // Overload << Operator // // acters that represent // Purpose : Display the 50 this datatype. // Written By : Dr. Thomas E. Hicks Environment : Windows NT // // Date : 10/25/00 Compiler : Visual C++ // ostream & operator << (ostream & OutputStream, S) OutputStream << setw(32) << P.Name; OutputStream << " " << setw(8) << S.No << " "; if (S.Sex == FEMALE) OutputStream << "Female"; else OutputStream << "Male "; return (OutputStream); # ifndef STUDENT_CLASS //========================================================= # ifndef STUDENT_CLASS //========================================================= // Includes # include <stdio.h> # include <iostream.h> # include <string.h> 1.hpp # define STUDENT_CLASS Why should each.hpp file should begin the compiler directive # ifndef [if not defined] // Defines # define STUDENT_CLASS # define MALE false # define FEMALE true and end with compiler directive # endif [end if]? # endif //STUDENT_CLASS //======================================================= // Class // class ( NewName[] = "", long NewNo = 0, bool NewSex = FEMALE); Prevent multiple redefinitions of constants, functions, etc. Several other classes may use/include (long NewNo, NewName[] = "", bool NewSex = FEMALE); ~ (void); void Set ( NewName[] = "", long NewNo = 0, bool NewSex = FEMALE); Stack <> Class(10); bool void Display( Message[] = ""); Name [26]; Sex; Interface - lists the class and its members -.h or.hpp LinkedList <> CSCI2320(25); BinaryTree <> CSCI4320(45); # define MALE false # define FEMALE true ; # endif //STUDENT_CLASS //======================================================= 39 # endif //STUDENT_CLASS //======================================================= 40 What is in the.h or.hpp erface? 1] All includes essential to the class 2] All defines essential to the class 3] All struct and class definitions 4] Prototypes for all Functions/Procedures 5] All Template Functions/Procedures/Methods # 7

8 What is in the.c or.cpp file? 1] Include the erface file 2] All non-template Functions/Procedures/Methods Why Partition Classes Into.hpp &.cpp Files? When a program is erfaced properly o.hpp and.cpp files: 1] Compilation Is Faster good compilers only compile those components that have been altered since the last compilation 2] Easier To Partition A Project For Teams 3] Reuse Opportunities Reduces Project Time/Cost - reuse opportunities increase when one develops and tests the class so well so general/generic that it can used in other projects 4] Assists In Better Design it is difficult, if not impossible, to keep all of the details of a large system in mind at one time by creating one self contained student class erface that has all of the functionality necessary for students, one can more easily abstract the object class Name Name ( NewFirst[]="", NewLast[]=""); *First, *Last; long ; Indigenous Data - Data that is completely contained by the structure. (i.e. No) Exogenous Data - Data that is not part of the structure, but accessed through poers that are in the structure. (i.e. First & Last) # 8

DirectAccessFiles.zip Open The Application Folder!

$Into Folder C:\Temp 49 50 50 It Should Compile!$

9 DirectAccessFiles.zip Open The Application Folder! Decompress Folder DirectAccessFiles.zip [From Schedule] Open The Debug Folder! Should Be Empty! Into Folder C:\Temp It Should Compile! 51 Compile The Program! Revisit The Debug Folder! Combined Binary Executable How Can We Execute It? ] Windows Mouse Double-Click 54 # 9

3] Set Debug Directory As The Default 2.

10 2.1] Hold Down Start Menu Select Run 2.2] Enter CMD 2.3] Set Debug Directory As The Default 2.4] Enter Main While We Are Here, How Does One Send The Output To A Text File, Called Output.txt? 2.4] Enter Main > Output.txt Open The Application Folder! Can Open Output.txt With Visual Studio Open The Debug Folder! Should Be Empty! More Extensive Listing Of Compile & Link Process # 10

obj Other files are non-readable system files that assist in the Automated Make Process! # include "Utilities.hpp" # include ".

11 Auto.obj is Re-compiled When Auto.hpp or Auto.cpp is altered or Rebuild All! Linker Links the Obj files to form Executable! Compile Successful Compilation Of Auto.hpp & Auto.cpp Creates Auto.obj Other files are non-readable system files that assist in the Automated Make Process! # include "Utilities.hpp" # include ".hpp" # include "Auto.hpp" # include "Part.hpp" There will be one obj file for each hpp/cpp set and one for Main Matrix - Two dimensional array X [5][2]; x [NoRows] [NoCols]; STL - Standard Template Library - Has Libraries For String, Vector, Stacks, etc # 11

12 67 67 # 12

RECOMMENDATION. Don't Write Entire Programs Unless You Want To Spend 3-10 Times As Long Doing Labs! Write 1 Function - Test That Function!

RECOMMENDATION. Don't Write Entire Programs Unless You Want To Spend 3-10 Times As Long Doing Labs! Write 1 Function - Test That Function! 1 2 RECOMMENDATION Don't Write Entire Programs Unless You Want To Spend 3-10 Times As Long Doing Labs! Write 1 Function - Test That Function! 2 Function Overloading C++ provides the capability of Using