For instance, a rose is a kind of flower, meaning that a rose is a specialized subclass of the more general class, flower. Associations represent relationships between classes; links represent relationships between objects. Class versus object Many people get confused by the difference between class and object. The interface of a class provides its outside view and therefore emphasizes the abstraction while hiding its structure and the secrets of its behavior. Each part of this abstraction denotes a particular property of our abstraction of an employee. Lets us differentiate between these two: Class Diagram helps construct the code for the software application development. The second is whole/part, which denotes a “part of” relation-ship. OBJECT ORIENTED ANALYSIS AND DESIGN MCQ WITH ANSWERS. Hybrid Inheritance − A combination of multiple and multilevel inheritance so as to form a lattice structure. Friendships break a class’s encapsulation and so, as in life, must be chosen carefully. For example, in retail telemarketing operations, we would find a one-to-one relationship between the class Sale and the class CreditCardTransaction: Each sale has exactly one corresponding credit card transaction, and each such transaction corresponds to one sale. ; or an intangible conceptual existence, like a project, a process, etc. 1. Multiple Inheritance − A subclass derives from more than one super-classes. In this sense, aggregation is a specialized kind of association. A class is a template for objects. Also, note that we have changed the state of the object designated by item3 by operating on it through its new indirect name, item4. For example, each instance of the class Customer might initiate a transaction with several instances of the class SalesPerson, and each such salesperson might interact with many different customers, generalization/specialization relationship (“is a” hierarchy among classes), “A subclass may inherit the structure and behavior of its superclass.”. A Class is a blueprint that is used to create Object. Cardinality of a binary association denotes the number of instances participating in an association. Thus, a petal is not a kind of a flower; it is a part of a flower. State that determines the characteristic properties of an object as well as the values of the properties that the object holds. Message passing essentially involves invoking class methods. : Class is a group of similar objects. Association . Approaches for identifying classes1. It represents an “is – a – kind – of” relationship. The benefits of using the object model are −. Specifically, if the method is declared as virtual, then late binding is employed, and the function is considered to be polymorphic. b. state . Unit 3 object analysis-classification 1. Noun phrase approach2. - Modifier: an operation that alters the state of an object, - Selector: an operation that accesses the state of an object but does not alter the state, - Iterator: an operation that permits all parts of an object to be accessed in some well-defined order, - Constructor: an operation that creates an object and/or initializes its state, - Destructor: an operation that frees the state of an object and/or destroys the object itself, Objects play many different roles during their lifetimes . For example, if we create an object of the class Rectangle, then the vtable will have an entry for the virtual function draw, pointing to the closest implementation of draw. 1. In this case, the class Temperature Controller still denotes the whole, and an instance of the class Heater is still one of its parts, although that part must now be accessed indirectly. Suppose now that we have some client object that wishes to draw all of the subclasses. 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