Relationship among classes in OOAD

1. RELATIONSHIP
AMONG CLASSES
PRESENTED BY-
MAHADEO RAJAK(205117051)
DHEERENDRA MEHAR(205117053)
GUIDED BY-
DR. B. RAMADOSS SIR
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2. WHAT IS RELATIONSHIP ?
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3. RELATIONSHIP
• Kind of connection
• State of being connected
• Related to one another
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4. RELATIONSHIP AMONG CLASSES
Consider for a moment the similarities and differences
among the following classes of objects:-
flowers, daisies, red roses, yellow roses, petals, and ladybugs. We can
make the following observations:-
• A daisy is a kind of flower.
• A rose is a (different) kind of flower.
• Red roses and yellow roses are both kinds of roses.
• A petal is a part of both kinds of flowers.
• Ladybugs eat certain pests such as aphids, which may be infesting
certain kinds of flowers.
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5. TYPES OF RELATIONSHIP
• Association
• Aggregation
• Using
• Inheritance
• Instantiation
• Metaclass
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6. ASSOCIATION
• Group of links having common structure.
• Communication between classes
• Depicts the relationship between objects of one or more
classes.
Link
• A link represents a connection through which an object collaborates
with other objects.
• Rumbaugh has defined it as “a physical or conceptual connection
between objects”.
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7. DEGREE OF AN ASSOCIATION
Degree of an association denotes the number of classes involved
in a connection.
• Self Association
Connects Objects of Same Class.
• Binary Association
Connects Objects of Two Classes.
• N-Array Association
Connects Objects of Three or More Classes.
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8. SELF ASSOCIATION
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9. BINARY ASSOCIATION
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10. N-ARRAY ASSOCIATION
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11. AGGREGATION
• Special Type of Association
• Directional Association
• Denotes whole/part hierarchy
• If a Class have Entity Reference
• Referred as PART-OF or HAS-A Relationship
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12. AGGREGATION EXAMPLE
class Address
{ string country, state; int pincode;
public Address( int pincode , string country, string state)
{ this.pincode=pincode;this.country=country;this.state=state; } }
class Employee
{
int id; string name;
Address addr; // an instance of class Address is a “PART OF” class Employee
}
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13. USING
• Using another class as a parater to a method
• Declares an object of that class local to one one of the
member function
• Allow the client access only to the public interface of the
supplier
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14. USING EXAMPLE
class TemperatureController { public:
TemperatureController(Location);
~TemperatureController();
void process(const TemperatureRamp&);
//TemperatureController uses the services of the class TemperatureRamp
Minute schedule(const TemperatureRamp&) const;
private: Heater h;
};
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15. INHERITANCE
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The capability of a class to drive properties and
characteristics from another class is called Inheritance.
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16. TYPES OF INHERITANCE
• Single Inheritance :
• Multiple Inheritance:
• Multilevel Inheritance:
• Hierarchical Inheritance:
• Hybrid Inheritance:
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17. SINGLE INHERITANCE:
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A subclass derives from a single super-class or base class.
MULTIPLE INHERITENCE
A subclass derives from more than one super-classes or
base class.
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18. MULTILEVEL INHERITANCE
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A subclass derives from a super-class which in turn is derived
from another class and so on.
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19. HIERARCHICAL INHERITANCE
• A class has a number of subclasses each of which may
have subsequent subclasses, continuing for a number of
levels, so as to form a tree structure.
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20. HYBRID INHERITANCE
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A combination of multiple and multilevel inheritance so as
to form a lattice structure.
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21. INSTANTIATION
• An instance of a class is called an object.
• Instantiation is used to create an object instance from a
class (instantiate)
• confusingly enough
• particular realization of an abstraction or template
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22. SYNTAX AND EXAMPLE
Syntax :
className objectName = new className(inputParameters);
Example:
//class looks like this
public class Car {
String make;
public Car(string make) {
this.make = make;
}
}
//instantiation, elsewhere in the program
Car myCar = new Car("Honda"); //passing in Honda into the make variable
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23. METACLASS
• A class whose instances are themselves classes
• Smalltalk and CLOS languages support
• C++ does not
• Not all object-oriented programming languages
support metaclasses
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24. METACLASS EXAMPLE
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25. REFERENCES
• Grady Booch “Object-Oriented Analysis and Design”
• Tutorialspoint(www.tutorialspoint.com)
• Youtube
• IBM Knowledge Center
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26. THANK YOU
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