Number 18 18. What is the difference between an is-a and a has-a relationship? How do you create a has-a relationship in your code?19. Imagine a Rectangle class with objects that represent two-dimensional rectangles. The Rectangle has width andheight fields with appropriate accessors and mutators, as well as getArea and getPerimeter methods.You would like to add a Square class into your system. Is it a good design to make Square a subclass ofRectangle? Why or why not?20. Imagine that you are going to write a program to play card games. Consider a design with a Card class and 52 sub-classes, one for each of the unique playing cards (for example, NineOf Spades and JackOfClubs). Is this a gooddesign? If so, why? If not, why not, and what might be a better design?21. In Section 9.2 we discussed adding functionality for dividend payments to the Stock class. Why was it preferable tocreate a DividendStock class rather than editing the Stock class and adding this feature directly to it?Section 9.5: Interfaces22. What is the difference between implementing an interface and extending a class?23. Consider the following interface and class:}public interface I {public void m1();public void m2();}public class C implements I {// code for class CWhat must be true about the code for class C in order for that code to compile successfully?

The goal of object-oriented programming (OOP), a programming paradigm, is to represent real-world…

Answered: 18. What is the difference between an…

18. What is the difference between an is-a and a has-a relationship? How do you create a has-a relationship in your code?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Number 22
C Sharp, I am trying to get my console to display the vehicle information, by using a base class of Vehicle and derived classes Car, and Truck. I have to add an interface to add and remove cars. But for now, I am just trying to get the vehicle information to display from the Car class. For some reason I am not able to override my methods in the derived classes. What am I am doing wrong ? using CarRentalCompany; using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace CarRentalCompany {//Define an abstract class Vehicle with properties like Make, Model, Year, Status, and Notes public abstract class Vehicle { public string make; public string model; public int year; public string status; public string notes; //Method to Display vechile information public void DisplayVehicleInfomration() { } } public class Car : Vehicle, IRentable {…
add a class to package that represents your new drivable type. That type should be something that is capable of being driven (speeding up and slowing down) and therefore a perfect candidate for a class that implements the actions in the Drivable interface.
Help, I am making a elevator simulation using polymorphism. I am not sure to do now. Any help would be appreciated. My code is at the bottom, that's all I could think off. There are 4 types of passengers in the system:Standard: This is the most common type of passenger and has a request percentage of 70%. Standard passengers have no special requirements.VIP: This type of passenger has a request percentage of 10%. VIP passengers are given priority and are more likely to be picked up by express elevators.Freight: This type of passenger has a request percentage of 15%. Freight passengers have large items that need to be transported and are more likely to be picked up by freight elevators.Glass: This type of passenger has a request percentage of 5%. Glass passengers have fragile items that need to be transported and are more likely to be picked up by glass elevators. public abstract class Passenger { public static int passangerCounter = 0; private String passengerID; protected…
Please help me create a cave class for a Hunt the Wumpus game (in java). You can read the rules in it's entirety of the Hunt the Wumpus game online to get a better idea of the specifications. It's an actual game. INFORMATION: The object of this game is to find and kill the Wumpus within a minimum number of moves, before you get exhausted or run out of arrows. There is only one way to win: you must discover which room the Wumpus is hiding in and kill it by shooting an arrow into that room from an adjacent room. The Cave The Wumpus lives in a cave of 30 rooms. The rooms are hexagonal. Each room has up to 3 tunnels, allowing access to 1, 2 or 3 (out of 6) adjacent rooms. The attached diagram shows the layout of rooms in the cave. The map wraps around such that rooms on the edges (white cells) have neighbors from the opposite edge (blue cells). E.g., the neighbors of room 1 are rooms 25, 26, 2, 7, 6, and 30, and you could choose to connect room 1 to any of these rooms. Observe how…
Write the missing code in the dark picture. This is not graded
B elow for each class you find a UML and description of the public interface. Implementing the public interface as described is madatory. There's freedom on how to implement these classes.The private properties and private methods are under your control.. There are multiple ways of implementing all these classes. Feel free to add private properties and methods. For each object, it's mandatory to create a header file (.h), implementation file (.cpp) and a driver. Blank files are included. The header should have the class definition in it. The implementation file should contain the implementations of the methods laid out in the header fine. And finally the Driver should test/demonstrate all the features of the class. It's best to develop the driver as the class is being written. Check each section to see if there are added additional requirements for the driver. Two test suites are included so that work can be checked. It's important to implement the drivers to test and demonstrate…
B elow for each class you find a UML and description of the public interface. Implementing the public interface as described is madatory. There's freedom on how to implement these classes.The private properties and private methods are under your control.. There are multiple ways of implementing all these classes. Feel free to add private properties and methods. For each object, it's mandatory to create a header file (.h), implementation file (.cpp) and a driver. Blank files are included. The header should have the class definition in it. The implementation file should contain the implementations of the methods laid out in the header fine. And finally the Driver should test/demonstrate all the features of the class. It's best to develop the driver as the class is being written. Check each section to see if there are added additional requirements for the driver. Two test suites are included so that work can be checked. It's important to implement the drivers to test and demonstrate…
elow for each class you find a UML and description of the public interface. Implementing the public interface as described is madatory. There's freedom on how to implement these classes.The private properties and private methods are under your control.. There are multiple ways of implementing all these classes. Feel free to add private properties and methods. For each object, it's mandatory to create a header file (.h), implementation file (.cpp) and a driver. Blank files are included. The header should have the class definition in it. The implementation file should contain the implementations of the methods laid out in the header fine. And finally the Driver should test/demonstrate all the features of the class. It's best to develop the driver as the class is being written. Check each section to see if there are added additional requirements for the driver. Two test suites are included so that work can be checked. It's important to implement the drivers to test and demonstrate…
Create a TestCard project with a TestCard class and a Card class. Data members for the Card class should be two numeric values representing the suit of the Card and the card's number. The Card class also has a constructor and methods for setting and getting the card information. See UML model. In the TestCard class within main(), deal two cards at a time by constructing two card objects. One card is the user's. The other is the computer's. Show both cards. Add a point to whoever had the higher card. Show who won the trick and the score. Scores don't change if a tie. Keep dealing until user wants to quit or 26 pairs have been dealt. UML for Card class -suit: int the number that corresponds to the suit of the card. 0 Hearts, 1 Diamonds, 2 Clubs, 3 Spades -value: int the value of the card. Ace is 1, 2 is 2, ..., Jack is 11, Queen 12, King 13. +Card() Default constructor. Sets the suit and number to random values +getValue(): int Returns the value of the…
Program this
Write classes that could be used in a system that manages vehicles in a public transportation system. You will write classes to represent a TransitVehicle, Bus, and SubwayCar. The information about the classes is below. Step 1: Plan Your Class Design Before you start to code, decide how to design your classes. Which class should be the parent? the child? What variables or methods belong in each class? Step 2: Write the Core Class Components Write the three classes. Each class must have all of the following. Important: a class can have a method directly (meaning written into the code) or indirectly (meaning inherited from a parent). Either of these counts to meet the requirement. instance data variables transit vehicles are described by an id that contains letters and numbers and a description of the route buses are described by an id, route, and the number of miles per gallon (without decimals) subway cars are described by an id, route, and whether or not the car goes underground…