Inheritance is used toa.Reduce code duplicationb.all of the abovec.Improve code reusabilityd.add relations with existing classes

5. Which feature of OOP indicates code reusability?a) Abstractionb) Polymorphismc) Encapsulationd) Inheritance

Illustrate how Java supports multiple inheritance.

What is the purpose of inheritance in Java? a.To allow code reuse and method overriding b.To import packages c.To declare variablesd.To secure data

rrect answerWhich of the following is used for implementing inheritance through class?Optionsinheritedextendsusingimplements

Module Detail2. Identify relationships between entitiesModule Detail3. Implement and test entitiesModule Detail4. Implement and test services and data repositoryModule Detail5. Finish up the projectModule Detail6. Takehome projectModule DetailOverviewMilestone1Relationships between ClassesMilestone2Cardinality and Object DiagramMilestone3Understand the CodinGame ProblemAssessmentWhat are Relationships between Classes?Objects of a class cannot operate solely on their own. They need to interact with the other active objects in the system to fulfill the requirements. While designing software, we need to study the interactions between objects and identify suitable relationships between them. Relationships help developers understand how the application will work with these objects. Relationships are code reusability at it’s best.For example, a car has 4 wheels. We can utilize the wheel class to create 4 wheel objects and attach it to the car object. The same wheel class may be reusable in many other cases as well.Let’s look at the different types of Class Relationships.Type of RelationshipsSource: Types of Class RelationshipsUses-A relationshipIt’s a relationship in which a method of class uses another class object for it’s behaviour.If one of these objects changes, the other object(s) can be impacted.Let’s understand the Uses-A relationship with an example.A player in a Ludo Game can move their token by a certain number of steps based on the number obtained by throwing a dice.A Player object has a responsibility to throw a Dice object to get the random number.Dice object is a dependency parameter for the method which implements the logic to throw a dice. Below code snippet would help you understand better. Here, the Player object Uses-A Dice object.class Dice { . . . . . . . . }class Player { . . . . . . . . public int throwDice(Dice dice){ return dice.getRandomNumber(); } . . . . . . . .}Is-A relationshipIt’s a relationship between two classes in which one class extends the another class.The class to be extended is a superclass and the extended class is a subclass.Let’s understand the Is-A relationship with an example.A company is opening its new office in Noida and is looking for furniture. Chair is among the furniture they need and they are looking to buy it at a cheaper price. They asked the dealer about the price of the chair. Dealer replied, "Which One?".There are many varieties of chairs in the market and we have to specify exactly what our requirements are. Each chair has its own speciality and features. We can assume that Chair is a superclass and the ArmChair and WheelChair are specialized versions (subclasses) of it.Below code snippet would help you understand better. Here ArmChair Is-A Chair.class Chair { . . . . . . . .}class WheelChair extends Chair { . . . . . . . .}class ArmChair extends Chair { . . . . . . . .}Has-A relationshipWhen an object of one class is created as a data member inside another class, this is the Has-A relationship. Let’s understand the Has-A relationship with an example.We know that a Brain is a part of a Animal. We can also rephrase the statement as "An animal has a brain". Can we imagine a brain living outside of an animal body? Doesn't make any sense, right? The existence of a brain makes sense only within the animal.Below code snippet would help you understand better.class Brain { . . . . . . . . } class Animal { Brain brain = new Brain(); . . . . . . . .}Types of Has-A relationshipAggregationAggregation is a type of Has-A relationship where two or more aggregated objects have their own lifecycle and can exist independently even if any of the others gets destroyed. One other object is the owner object of these aggregated objects.The owner object is called an aggregating object and its class is called an aggregating class. The aggregating class has a reference to another class and is the owner of that other class.For example, an Employee has an address.Here, Employee is an owner object of this relationship. Both of the objects have their own lifecycle. Addresses will continue to exist even if the employee no longer stays at the mentioned address.CompositionComposition is a special type of Has-A relationship which is a more restrictive form of aggregation. The owner object as a whole cannot exist without the other object. The aggregating object is highly dependent on the other object.For example, a hotel has a number of rooms.Here, a hotel is an owner object which has an exclusive relationship with the room object. A hotel can control the lifecycle of a Room object. A room cannot exist without the hotel and vice versa.Quiz1Which type of relationship is modeled by Inheritance? *Is-A relationshipHas-A relationshipUses-A relationship2A Building contains many Apartments? What class relationship could be present between Building and Apartment? *CompositionAggregationDirect AssociationDependency3For a Battle Survival Game, Player class can have various kinds of items such as a Medical Kit, Ammunition, Petrol Can, Grenade, etc. These items can be dropped and picked up by other players.What class relationship could be present between Player and these items ? *