OOPS Concept Ppt

8/13/2019 OOPS Concept Ppt

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PROGRAMMING 3 (Common to CSE & IT)

Aim: To understand the concepts of object-oriented programming and master OOP using C++

Unit I9

Object oriented programming concepts ! objects ! c"asses ! methods and messages ! abstraction and encapsu"ation! inheritance ! abstract c"asses ! po"#morphism Introduction to C++ ! c"asses ! access specifiers ! function anddata members ! defau"t arguments ! function o$er"oading ! friend functions ! const and $o"ati"e functions !static members ! Objects ! pointers and objects ! constant objects ! nested c"asses ! "oca" c"asses

Unit II9

Constructors ! defau"t constructor ! Parameteri%ed constructors ! Constructor ith d#namic a""ocation ! cop#constructor ! destructors ! operator o$er"oading ! o$er"oading through friend functions ! o$er"oading theassignment operator ! t#pe con$ersion ! e'p"icit constructor

Unit III9

unction and c"ass temp"ates - E'ception hand"ing ! tr#-catch-thro paradigm ! e'ception specification ! terminateand ne'pected functions ! ncaught e'ception

Unit IV9

Inheritance ! pub"ic* pri$ate* and protected deri$ations ! mu"tip"e inheritance ! $irtua" base c"ass ! abstract c"ass !composite objects untime po"#morphism ! $irtua" functions ! pure $irtua" functions ! TTI ! t#peid ! d#namiccasting ! TTI and temp"ates ! cross casting ! do n casting

Unit V9

Streams and formatted I,O ! I,O manipu"ators - fi"e hand"ing ! random access ! object seria"i%ation ! namespaces -std namespace ! .SI String Objects ! standard temp"ate "ibrar#

Total: 4

TE!T BOO"S:/ 0 Tri$edi* 1Programming ith .SI C++2* O'ford ni$ersit# Press* 3445RE#ERENCES:/ Ira Poh"* 1Object Oriented Programming using C++2* Pearson Education* SecondEdition eprint 34463 S 0 7ippman* 8osee 7ajoie* 0arbara E 9oo* 1C++ Primer2* ourth Edition*Pearson Education* 344:; 0 Stroustrup* 1The C++ Programming "anguage2* Third edition* Pearson


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Unit I

Object oriented programming concepts !objects ! c"asses ! methods and messages! abstraction and encapsu"ation !

inheritance ! abstract c"asses !po"#morphismIntroduction to C++ ! c"asses ! access

specifiers ! function and data members !defau"t arguments ! function o$er"oading! friend functions ! const and $o"ati"efunctions ! static members ! Objects !pointers and objects ! constant objects !nested c"asses ! "oca" c"asses


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;

ObjectsAn o$%&'t i( an &n'a)(*lation o+ $ot, +*n'tion( an- -ata

Objects are an Abstraction represent real world entities Classes are data types that define shared common properties or

attributes Objects are instances of a class "" objects ha$e attributes (characteristics)* this is sometimes referred

to as state Objects have State

have a value at a particular time Objects have Operations

associated set of operations called methods that describe how tocarry out operations (behavior)

Objects have Messages request an object to carry out one of its operations by sending it a

message messages are the means by which we exchange data between objects


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Cla((&( Cla(( :


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c"asses E$er# object be"ongs to (is an instance of) a

c"ass n object ma# ha$e fie"ds * or $ariab"es

The c"ass describes those fie"ds

n object ma# ha$e methods The c"ass describes those methods n bstract >ata T#pe ( >T) bund"es

together? some data* representing an object or @thing@ the operations on that data

The operations defined b# the >T are theonly operations permitted on its data

E'am "e? a Checkin Account * ith o erations


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Prob"em? printing student mar= sheet C"ass student ea" or"d entities? student* teacher* subject* mar= sheet etc

C"ass studentAPub"ic ?

int o"".oB string nameB string addressB $oid Print>etai"s() A cout ro""noB cout nameB cout addressB D

DB


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TV.0/ Cla(( an- 3In(tan'&(


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Object-Oriented Concept The rectang"e area prob"em >efine a c"ass? ect

>ata? idth* "ength unctions? compute area()

n object? an instance of the c"assect To So"$e the prob"em* create an object

of ect* and reFuest this object to returnthe area of the rectang"e


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Encapsu"ation

class Circle{

private:int radius

public: Circle(int r);

// The area of a circleint compute_area();

};

class Trian le{

private:int ed ea! ed eb! ed ec;

public: Trian le (int a! int b! int

c);

// The area of a trian leint compute_area();

};


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"#ample Codeclass $ect{

private: int %idth! len th;public:

$ect (int %! int l){ %idth & %; len th & l;}

int compute_area(){ return %idth'len th;}

}

main(){

$ect rect ( !*); int #;

#&rect +compute_area();cout,,#,,endl;

}


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M&t,o-( M&((a1&(

G S&n-in1 a m&((a1& i( o* a o+:! int& a'tin1 it, o$%&'t(5! mani)*latin1 an o$%&'t6( (tat&5

T&ll( t,& o$%&'t ,at to -o it, it(&l+E7am)l&: To ',an1& t,& ',ann&l on TV

! 8& *(& t,& ',ann&l (&l&'tion $*tton( T,i((&n-( a m&((a1& t,at & ant to (&l&'t an& ',ann&l

! T,& TV &()on-( to t,& m&((a1& $(&l&'tin1 an- &7&'*tin1 a method.

! T,& TV no &'&i &( a n& (i1nal ,i', i(t,& ',ann&l & (&l&'t&-


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M&t,o-! T&ll( t,& o$%&'t ,o to &()on- to a m&((a1&O* TV.0/ o$%&'t( &()on- to t,&+ollo in1 m&((a1&(:

! T* n t,& t&l& i(ion (&t on o o++ ! C,an1& t,& ',ann&l! C,an1& t,& ol*m&


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Characteristics of OOP7

En'a)(*lation: Combining data structure ithactions >ata structure? represents the properties* the states* or

characteristics of objects ctions? permissib"e beha$iors that are contro""ed through the

member functions>ata hiding? Process of ma=ing certain datainaccessib"e

In,& itan'&: bi"it# to deri$e ne objects fromo"d ones permits objects of a more specific c"ass to inherit the properties

(data) and beha$iors (functions) of a more genera",base c"ass abi"it# to define a hierarchica" re"ationship bet een objects

Pol mo ),i(m: bi"it# for different objects tointerpret functions different"#


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O-O Princip"es and C++Constructs

O-O Concept C++ Construct(s)

bstraction C"assesEncapsu"ation C"assesInformation Hiding Pub"ic and Pri$ate

9embersPo"#morphism Operator

o$er"oading* tem "ates $irtua"


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OOP eatures

6 major features in OOP encapsu"ation

information hiding inheritance o$er"oading


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Encapsu"ation an o$%&'t &n'a)(*lat&( $ot, it(

att i$*t&( m&t,o-( imp"ications?

an attribute, method is attached to an object,c"ass

hen #ou mention an attribute, methods* #ouha$e to specif# hich object, c"ass it comesfrom

h# encapsu"ation hen #ou get ho"d of an object* #ou a"so get

ho"d of its data & beha$iour components good for reuse


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Information Hiding an o$%&'t 'an ,i-& it( int& nal -&tail(

e g #ou donJt =no ho #our mobi"eJse"ectronics or=s e'cept punching the buttons

can se"ecti$e"# sho some detai"s to theoutside or"d e g #our mobi"e on"# sho s the number it dia"s

defines an 1interface2 to interact ith the

outside or"d e g #our mobi"e interacts ith #our throughthe buttons & screen


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Inheritance

a 'la(( ma $& (imila to anot,&'la(( $*t $&in1 mo & ()&'iali(&- e g the c"ass 1student2 is simi"ar to the

c"ass 1person2 but 1student2 is morespecia"ised

a person has attributes "i=e? se'* age* name

a student has a"" these + a student no


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Inheritance (contJd) a subclass

e'tends, specia"ises a superclass inherits attributes & methods from its

superclass

ma# ha$e more attributes, methods than itssuperclass ma# change the content, procedure of an

inherited method i e same method name, signature but different

beha$iour h# inheritance reuse e'isting c"ass definition customise, specia"ise if needed


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O$er"oading different functions, procedures, methods

can ha$e the same name pro$ided that the parameters are of different

t#pes gi$ing a uniFue 1signature2

the s#stem i"" figure out hich one to in$o=e e g #ou can ha$e 3 procedures* both named

1call 2* ta=ing a 1dog2 or 1person2 object as

parameter respecti$e"# >epending on #ou gi$eit a 1dog2 or 1person2 object as the parameter* 8a$a i"" =no hich one to use


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Encapsu"ation is the mechanism that bindstogether code and data* and =eeps both safefrom outside interference or misuse

/ 0oth data and member functions treated assing"e unit3 bstract focuses on beha$ior of object*encapsu"ation focuses on actua" imp"ementation

; Encapsu"ation achie$ed through data hiding6 or abstractions to or=* imp"ementationsmust be encapsu"ated


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-bstract T.pes

class hape{

public: hape();

// Calculate the area for// this shapevirtual int compute_area() & 0;

};


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0ST CTIO. .>E.C PS 7 TIO.

Definition : 1ata "ncapsulation or 2nformation 3idin is theconcealin of the implementation details of a data ob4ectfrom the outside %orld+

Definition : Data Abstraction is the separation bet%eenthe specification of a data object and its implementation + Definition : - data type is a collection of objects and a set

of operations that act on those ob4ects+

Definition : -n abstract data type (ADT) is a data t.pethat is or ani5ed in such a %a. that the specification of theob4ects and the specification of the operations on theob4ects is separated from the representation of the ob4ectsand the implementation of the operation


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d$antages of >ata bstraction and>ata Encapsu"ation

Simp"ification of soft arede$e"opment Testing and >ebugging

eusabi"it# 9odifications to the representation ofa data t#pe


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-bstract Classes

6a. Contain abstract methods ome methods and data ma. be definedabstract class Coloured hape {private Colour c; // stora e allocated for each

public abstract void dra%();public Colour etColour() {return c;}public abstract void erase();

} 7o instances allo%ed ubclasses must implement all abstract methods or the. are also abstract


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Florida Community College at Jacksonville

Object-oriented Principle -

Inheritance Inheritance is the process by which one object

acquires the properties of another object. By use ofinheritance, an object need only define all of itscharacteristics that make it unique within its class, itcan inherit its eneral attributes from its parent.

29 of 10 slides

!ccount

"heckin #ort a e $oan

COP 2551 Object Oriented Programming OO Conce!ts Overvie"


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Florida Community College at Jacksonville

Object-oriented Principle %

&ncapsulation &ncapsulation is the mechanism that binds to ether

the code and the data it manipulates, and keeps bothsafe from outside interference and misuse.

#0 of 10 slides

A Class

Pri'ate 'ariablesand methods

Public 'ariables and methods

Public 'ariables is not recommended

COP 2551 Object Oriented Programming OO Conce!ts Overvie"


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Encapsu"ation Hides the imp"ementation detai"s of a

c"ass orces the user to use an interface to

access data

9a=es the code more maintainab"e PI doc as an e'amp"e


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27T$ 1


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=asic C "#tension from Ccomments

/* You can still use the old comment style, *//* but you must be very careful about mixing them */// It's best to use this style for 1 line or partial lines/* And use this style when your comment

consists of multiple lines */

cin and cout (and >include ,iostream+h?)cout !"ello#$char name%1& $cin (( name$cout !"i, # name #, nice name)# endl$

cout endl$ // print a blan line declarin variables almost an.%here // declare a variable when you need it for +int 1$ -$ ..

0 char a m2$

cout a$


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C7 SSES


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Kraphica" epresentationof C"asses

co"ournamehere

attributes(data

component)

methods(proceduralcomponent)

interfaceto the

outside world a"=s imbar=

the Do1 c"assthe P& (on c"ass

nameo n

a"=instruct

rite emai"


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Kraphica" epresentationof Objects

co"our? hite,bro nname? 7assiehere? nnur

a"=s imbar=

name? a$io n? 7assie

a"=instruct

rite emai"

a$i* a P& (on object Lassie * a Do1 objectco"our? #e""o

name? Pa=ihere? '''

a"=s imbar=

Pa=i* a Do1 object

L* another Do1 object

name? ajao n? nu""

a"=instruct

rite emai"

aja* a P& (on object

L* another Do1 objectL* another P& (on object


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ccess specifiers Specif# hether the data defined i"" be

a$ai"ab"e to the users of the objects of thec"ass

Pub"ic Pri$ate Protected

Pub"ic? the data defined under pub"ic isa$ai"ab"e to objects Pri$ate? data defined under pri$ate is not

a$ai"ab"e to objects

C"ass student


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APub"ic ? int o"".oB pri$ate? string nameB string addressB

pub"ic?

$oid Print>etai"s() A cout ro""noB cout nameB

cout addressB DDB $oid main()A student student/B student/ o"".oM 5B student/ nameM 1N2B ,, does not or= since name is pri$atestudent/ addressM 1 2B ,, does not or= since name is pri$ateStudent/ Print>etai"s()BD


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unction and data member unctions can be defined either inside or outside the

c"ass >efining function members outside c"ass/ $er# simp"e to define functions outside c"ass3 If the functions are big define outside

Static data members of c"ass/ Static members are stored at a "ocation here the# areretained throughout the e'ecution of the program andare not stored ith c"ass objects

3 Stored on"# as a sing"e cop#! simi"ar to memberfunctions

; "" the static data members are initia"i%ed to %ero at thetime of dec"aration

C"ass student ,,defining function members outside c"ass


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APub"ic ? int o"".oB string nameB string addressB

$oid Print>etai"s()B ,,protot#pe DB

$oid student ?? Print>etai"s() A

cout ro""noB cout nameB cout addressB DDB $oid main()

A student student/B student/ o"".oM 5B student/ nameM 1N2Bstudent/ addressM 1 2BStudent/ Print>etai"s()BD

c"ass student


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A pub"ic? static int Passing9ar=B int Subject9ar=Q:RB boo" fai"B $oid >isp"a#9ar=s() A for (int iM4Bi :B++i) A cout 19ar=s of subject .o 2B cout i 1is2 Subject9ar=QiRB D

D $oid Set9ar=s (int 9ar=sQ:R

A for (int iM4B i :B ++i) A Subject9ar=sQiRM9ar=sQiRB DD boo" Chec=Passing()A fai"Mfa"seB

for (int iM4Bi :B ++i) A if (Subject9ar=QiR Passing9ar=)fai"M trueB

D if (fai") cout 1congratu"ations ou are passing n2B e"se cout 1sorr# ou are fai"ing n2B

return fai"B


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D&+a*lt A 1*m&nt(

defau"t argument is a $a"ue gi$enin the +*n'tion -&'la ation thatthe compi"er automatica""# inserts ifthe ca""er does not pro$ide a $a"uefor that argument in the +*n'tion'all5

S#nta'?

return_type f (@! type # & default_value !@);


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D&+a*lt A 1*m&nt((E'amp"es)

The defau"t $a"ue of the 3 nd argument is 3

This means that if the programmerca""s )o (')* the compi"er i""rep"ace that ca"" ith )o ('*3)*returning ' 3

double pow (double #! int n&9)

// computes and returns #n


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D&+a*lt A 1*m&nt(( u"es)

Once an argument has a defau"t$a"ue* a"" the arguments after itmust ha$e defau"t $a"ues

Once an argument is defau"ted in afunction ca""* a"" the remainingarguments must be defau"ted

int f (int #! int .&0! int n)// ille al

int f (int #! int .&0! int n& )// le al


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unction o$er"oading unction redefined ith different set of

argumentsEN? add(f"oat* f"oat) dd(int* int) dd (int* int* int) unction o$er"oading is usefu" hen simi"ar

function is reFuired to be ca""ed ith either$ariab"e number of arguments or arguments ofdifferent t#pe or both


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8,at i( a # i&n- #*n'tion;


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friend function is used for accessing the non-pub"ic members of a c"ass c"asscan a""o non-member functions and other c"asses to access its o n pri$ate data*b# ma=ing them friends Thus* a friend function is an ordinar# function or a memberof another c"ass


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riend functionc"ass c"ass/Apri$ate?int numB

pub"ic?$oid get()Acout @.umber?@BcinXXnumBDfriend $oid disp"a#(c"ass/ c")BDB$oid disp"a#(c"ass/ c/)Acout C/ . 9BDint main()

Ac"ass/ c"sBc"s get()Bdisp"a#(c"s)BD

,,static member friend function matri' mu"tip"ication


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Zinc"ude iostream hXZinc"ude conio hX c"ass matri'$ectorA

static int aQ;RQ;RBstatic int bQ;RBstatic int cQ;RBpub"ic?$oid getmatri'($oid)B$oid get$ector($oid)Bfriend int mu"tip"#(matri'$ector m$)

DB int matri'$ector??aQ;RQ;RBint matri'$ector??bQ;RBint matri'$ector??cQ;RB $oid matri'$ector??getmatri'($oid)Acout @ n enter the matri' $a"ue n@Bfor(int iM4Bi ;Bi++)A

for(int jM4Bj ;Bj++)AcinXXaQiRQjRBD

DD

$oid matri'$ector??get$ector($oid)A


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Acout @ n@B

cout @ n enter the $ector ?@Bfor(int =M4B = ;B=++)

AcinXXbQ=RB

DD int mu"tip"#(matri'$ector m$)Acout @matri' - $ector mu"tip"ication n@Bcout @ n the $ector n@B

for(int mM4Bm ;Bm++)Acout @ n@Bcout m$ bQmRBD

cout @ n the matri' n@B

for(int iM4Bi ;Bi++)Afor (int jM4B j ;B j++)Acout m$ aQiRQjRBcout @ t@B

D

cout @ n@B


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cout @ n@B Dfor(int eM4Be ;Be++)A

for(int dM4Bd ;Bd++)

Am$ cQeRMm$ cQeR+m$ aQeRQdR[m$ bQdRBDD

cout @ n the resu"t is n@Bfor(int nM4Bn ;Bn++)A

cout m$ cQnRBcout @ n@BDreturn 4BD int main()Ac"rscr()Bmatri'$ector m$Bm$ get$ector()Bm$ getmatri'()Bmu"tip"#(m$)Bgetch()Breturn 4BD

' ( & $& * ' i (


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'on(t m&m$& +*n'tion( function* hich guarantees not to

modif# the in$o=ing object

If the bod# of the const functioncontains a statement that modifies thein$o=ing object* the program does notcompi"e

One e'ception here is the mutab"emember mutab"e data member can bemodified b# const function


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\o"ati"e functions

member function in$o=ed b# a$o"ati"e object

$o"ati"e object ]s $a"ue can bechanged b# e'terna" parametershich are not under the contro" ofthe program

olatil& m&m$& +*n'tion( >ec"are a member function ith the$ " i" ifi h i b "" d f "# f $ " i"


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$o"ati"e specifier to ensure that it can be ca""ed safe"# for a $o"ati"eobject?

c"ass 0 A int 'Bpub"ic?$oid f() $o"ati"eB ,, $o"ati"e member function DB

int main() A $o"ati"e 0 bB ,, b is a $o"ati"e object

b f()B ,, ca"" a $o"ati"e member function safe"#D

The object b is dec"ared $o"ati"e Ca""ing a non-$o"ati"e memberfunction from this object is unsafe* because b^s state might ha$ebeen changed b# a different thread in the meantime

To ensure that f() can be ca""ed safe"# for a $o"ati"e object* it^s


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Pointers and objects

int x = 10;int *p;

p = &x;

p ets the address of x in memor.+

p

x10


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""ocating memor# using n&

Point *p = new Point(5, 5);

new a""ocates space to ho"d the object new ca""s the objectJs constructor new returns a pointer to that object

> "" ti # i


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>ea""ocating memor# using-&l&t&

// allocate memoryPoint *p = new Point(5, 5);

// !ree t"e memory#elete p;

or e$er# ca"" to new * there must bee'act"# one ca"" to #elete


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sing n& ith arra#s

int x = 10;int* n$m%1 = new int 10'; // oint* n$m%2 = new int x'; // o

Initia"i%es an arra# of /4 integers on theheap

A )oint& 'an )oint to an o$%&'t ' &at&- $ a


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) ) $ $'la((5

O$%&'t )oint& ( a & *(&+*l in ' &atin1 o$%&'t( at

*n tim&5 student s/B student [ptr M &s/B s/ getdata()B

s/ sho ()B eFui$a"ent to ptr-Xgetdata()B ptr-X sho ()B or ([ptr) sho ()B e can a"so create the objects using pointers and

ne operator student [ptr M ne studentB This a""ocates enough memor# for the data members in

the object structure and assigns the address of thememor# space to ptr


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constant objects const student s/('*#)B ,, object s/ is constant n# attempt to modif# the $a"ues of ' and # i""

generate compi"e time error constant object can ca"" on"# constant member

functions $oid Print>etai"s()const A cout ro""noB

cout nameB cout addressBD

nested c"asses


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nested c asses It is an another a# of inheriting properties of one

c"ass into another rom this e can understand that an object can be

co""ection of man# other objects* that is a c"ass cancontain objects of other c"asses as its members

c"ass a"pha(L)B c"ass beta(L)B c"ass gamma A

a"pha a/B beta b/B DB"" objects of gamma c"ass i"" contain the objects a/

and b/ This =ind of re"ationship is ca""ed

"oca" c"asses


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oca c asses C"asses can be defined and used inside a function or a b"oc= Such c"asses are

ca""ed "oca" c"asses $oid test(int a) ,,function AL

c"ass student ,,"oca" c"ass A

L ,,c"ass definitionL DBLL student s/(a)B ,,create student objectLLD7oca" c"asses can use g"oba" $ariab"es and static $ariab"es dec"ared inside the

functionEnc"osing function cannot access the pri$ate member of a "oca" c"ass


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C++ - d$ance E'tension

C++ a""o function o$er"oading In C++* functions can use the same

names* ithin the same scope* if

each can be distinguished b# itsname and signature

The signature specifies the

number* t#pe* and order of theparameters The name p"us signature * then*

uniFue"# identifies a function


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Take Home Message There are man# different =inds of

programming paradigms* OOP is oneamong them

In OOP* programmers see the e'ecutionof the program as a co""ection ofdia"oging objects

The main characteristics of OOP7 inc"udeencapsu"ation* inheritance* andpo"#morphism .ot on"# OOP7 can doOOP* b t " th

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OOPS Concept Ppt