Answer / md zakaullah

BASIC 4 CONCEPTS OF OOPS:

1. DATA ABSTRACTION
2. DATA ENCAPSULATION
3. INHERITANCE
4. POLYMORPHISM

Answer / mithu

1.class
2.object
3.inhritance
4.polymorphism
5.encapsulation
6.message passing
7.dynamic binding
8.data abstraction

Answer / hari

OBJECT
ENCAPSULATION
INHERITANCE
POLYMORPHISM
OVERRIDING
MESSAGE PASSING

Answer / ramalakshmi

Oops Concepts are :

1.Class
2.Object
3.Data Encapsulation
4.Data Abstraction
5.Inheritance
6.Polymorphism
7.Dynamic Binding
8.Message Passing

Answer / kvcodes

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Answer / komichi

The basic OOP concepts are:
1. Data abstraction
2. Data encapsulation
3. Inheritance
4. Polymorphism

Answer / amsma

Class
Defines the abstract characteristics of a thing (object), including the thing's characteristics (its attributes, fields or properties) and the thing's behaviors (the things it can do, or methods, operations or features). One might say that a class is a blueprint or factory that describes the nature of something. For example, the class Dog would consist of traits shared by all dogs, such as breed and fur color (characteristics), and the ability to bark and sit (behaviors). Classes provide modularity and structure in an object-oriented computer program. A class should typically be recognizable to a non-programmer familiar with the problem domain, meaning that the characteristics of the class should make sense in context. Also, the code for a class should be relatively self-contained (generally using encapsulation). Collectively, the properties and methods defined by a class are called members.
Object
A pattern (exemplar) of a class. The class of Dog defines all possible dogs by listing the characteristics and behaviors they can have; the object Lassie is one particular dog, with particular versions of the characteristics. A Dog has fur; Lassie has brown-and-white fur.
Message passing
"The process by which an object sends data to another object or asks the other object to invoke a method." Also known to some programming languages as interfacing. For example, the object called Breeder may tell the Lassie object to sit by passing a "sit" message which invokes Lassie's "sit" method. The syntax varies between languages, for example: [Lassie sit] in Objective-C. In Java, code-level message passing corresponds to "method calling". Some dynamic languages use double-dispatch or multi-dispatch to find and pass messages.
Inheritance
"Subclasses" are more specialized versions of a class, which inherit attributes and behaviors from their parent classes, and can introduce their own.
For example, the class Dog might have sub-classes called Collie, Chihuahua, and GoldenRetriever. In this case, Lassie would be an instance of the Collie subclass. Suppose the Dog class defines a method called bark() and a property called furColor. Each of its sub-classes (Collie, Chihuahua, and GoldenRetriever) will inherit these members, meaning that the programmer only needs to write the code for them once.
Each subclass can alter its inherited traits. For example, the Collie class might specify that the default furColor for a collie is brown-and-white. The Chihuahua subclass might specify that the bark() method produces a high pitch by default. Subclasses can also add new members. The Chihuahua subclass could add a method called tremble(). So an individual chihuahua instance would use a high-pitched bark() from the Chihuahua subclass, which in turn inherited the usual bark() from Dog. The chihuahua object would also have the tremble() method, but Lassie would not, because she is a Collie, not a Chihuahua. In fact, inheritance is an "a... is a" relationship between classes, while instantiation is an "is a" relationship between an object and a class: a Collie is a Dog ("a... is a"), but Lassie is a Collie ("is a"). Thus, the object named Lassie has the methods from both classes Collie and Dog.
Multiple inheritance is inheritance from more than one ancestor class, neither of these ancestors being an ancestor of the other. For example, independent classes could define Dogs and Cats, and a Chimera object could be created from these two which inherits all the (multiple) behavior of cats and dogs. This is not always supported, as it can be hard both to implement and to use well.
Abstraction
Abstraction is simplifying complex reality by modeling classes appropriate to the problem, and working at the most appropriate level of inheritance for a given aspect of the problem.
For example, Lassie the Dog may be treated as a Dog much of the time, a Collie when necessary to access Collie-specific attributes or behaviors, and as an Animal (perhaps the parent class of Dog) when counting Timmy's pets.
Abstraction is also achieved through Composition. For example, a class Car would be made up of an Engine, Gearbox, Steering objects, and many more components. To build the Car class, one does not need to know how the different components work internally, but only how to interface with them, i.e., send messages to them, receive messages from them, and perhaps make the different objects composing the class interact with each other.
Encapsulation
Encapsulation conceals the functional details of a class from objects that send messages to it.
For example, the Dog class has a bark() method. The code for the bark() method defines exactly how a bark happens (e.g., by inhale() and then exhale(), at a particular pitch and volume). Timmy, Lassie's friend, however, does not need to know exactly how she barks. Encapsulation is achieved by specifying which classes may use the members of an object. The result is that each object exposes to any class a certain interface — those members accessible to that class. The reason for encapsulation is to prevent clients of an interface from depending on those parts of the implementation that are likely to change in future, thereby allowing those changes to be made more easily, that is, without changes to clients. For example, an interface can ensure that puppies can only be added to an object of the class Dog by code in that class. Members are often specified as public, protected or private, determining whether they are available to all classes, sub-classes or only the defining class. Some languages go further: Java uses the default access modifier to restrict access also to classes in the same package, C# and VB.NET reserve some members to classes in the same assembly using keywords internal (C#) or Friend (VB.NET), and Eiffel and C++ allow one to specify which classes may access any member.
Polymorphism
Polymorphism allows the programmer to treat derived class members just like their parent class' members. More precisely, Polymorphism in object-oriented programming is the ability of objects belonging to different data types to respond to method calls of methods of the same name, each one according to an appropriate type-specific behavior. One method, or an operator such as +, -, or *, can be abstractly applied in many different situations. If a Dog is commanded to speak(), this may elicit a bark(). However, if a Pig is commanded to speak(), this may elicit an oink(). They both inherit speak() from Animal, but their derived class methods override the methods of the parent class; this is Overriding Polymorphism. Overloading Polymorphism is the use of one method signature, or one operator such as "+", to perform several different functions depending on the implementation. The "+" operator, for example, may be used to perform integer addition, float addition, list concatenation, or string concatenation. Any two subclasses of Number, such as Integer and Double, are expected to add together properly in an OOP language. The language must therefore overload the addition operator, "+", to work this way. This helps improve code readability. How this is implemented varies from language to language, but most OOP languages support at least some level of overloading polymorphism. Many OOP languages also support Parametric Polymorphism, where code is written without mention of any specific type and thus can be used transparently with any number of new types. Pointers are an example of a simple polymorphic routine that can be used with many different types of objects.

Answer / amit sharma

It may be

Answer / anithadurairaj

OOPS-Object Oriented Programming.
It is one of the most popular methodologies in Software
development.
It offers a powerful model for creating Computer
programs.It spreads the program development
process,improves maintenance and enhances reusability of
programs.

Answer / rajeev shishodia

Simple meaning of OOPS is Object Oriented Programming Skill.
Which is programming language work on the following 3
features as known as OOPS based language?
1. Encapsulation / Abstraction
2. Inheritance
3. Polymorphism

Which is faster post increment or pre increment ? and in which cases should u use either - to increase speed?

4 Answers   EA Electronic Arts,

String = "C++ is an object oriented programming language.An imp feature of oops is classes and objects".Write a pgm to count the repeated words from this scenario?

0 Answers   HCL,

what does exactly the linker do?

1 Answers  

Can abstract class have normal methods?

0 Answers  

Name a typical usage of polymorphism

3 Answers  

what are the disadvantages of C++?

25 Answers   ATS, Infosys, UNI, Wipro,

Can we have a private virtual method ?

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What is the output of the following code: int v() { int m=0; return m++; } int main() { cout<<v(); } 1) 1 2) 0 3) Code cannot compile

4 Answers  

What are oops functions?

0 Answers  

When will a constructor executed?

5 Answers   TCS,

//what is wrong with the programme?? #include<iostream.h> template <class first> class dd { first i; public: void set(); void print(); }; void dd< first>:: set() { cin>>i; } void dd< first>::print() { cout<<"\n"<<i; } void main() { dd <char>g; g.set(); g.print(); }

1 Answers  

What is the main difference between C++ and Java

11 Answers   TCS,