Purpose To review interfaces Directions Your task for this lab is to implement and test a class to store ratings of items. Your Rating class should have the following fields and methods: private double sumOfRatings - the sum of all of the ratings private int raters - the number of people who have rated an item public Rating () - initialize both fields to zero public Rating (double sumOfRatings, int raters) initialize the fields to the parameter values public void addRating (double newRating) - increase the sumOfRatings by newRating and increase the number of raters by one public double getAverageRating () return the average rating; if there are no raters so far, return 0.0 public String toString() - display the average rating and how many reviews it is based on; for example, if the sum of the ratings is 32 and that is based on ratings from ten people, the toString method will return "3.2 based on 10 reviews"

Purpose To review interfaces Directions Your task for this lab is to implement and test a class to store ratings of items. Your Rating class should have the following fields and methods: private double sumOfRatings - the sum of all of the ratings private int raters - the number of people who have rated an item public Rating () - initialize both fields to zero public Rating (double sumOfRatings, int raters) initialize the fields to the parameter values public void addRating (double newRating) - increase the sumOfRatings by newRating and increase the number of raters by one public double getAverageRating () return the average rating; if there are no raters so far, return 0.0 public String toString() - display the average rating and how many reviews it is based on; for example, if the sum of the ratings is 32 and that is based on ratings from ten people, the toString method will return "3.2 based on 10 reviews"

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

See similar textbooks

Similar questions

Dice Rolling Class In this problem, you will need to create a program that simulates rolling dice. To start this project, you will first need to define the properties and behaviors of a single die that can be reused multiple times in your future code. This will be done by creating a Dice class. Create a Dice class that contains the following members: Two private integer variables to store the minimum and maximum roll possible. Two constructors that initialize the data members that store the min/max possible values of rolls. a constructor with default min/max values. a constructor that takes 2 input arguments corresponding to the min and max roll values Create a roll() function that returns a random number that is uniformly distributed between the minimum and maximum possible roll values. Create a small test program that asks the user to give a minValue and maxValue for a die, construct a single object of the Dice class with the constructor that initializes the min and max…
Assignment:The BankAccount class models an account of a customer. A BankAccount has the followinginstance variables: A unique account id sequentially assigned when the Bank Account is created. A balance which represents the amount of money in the account A date created which is the date on which the account is created.The following methods are defined in the BankAccount class: Withdraw – subtract money from the balance Deposit – add money to the balance Inquiry on:o Balanceo Account ido Date created
Rainfall Type Create a RainFall class that keeps the total rainfall in an array of doubles for each of the 12 months. Methods in the programme should return the following values: • the total annual rainfall; • the average monthly rainfall • the wettest month of the year • the month with the least amount of rain Demonstrate the class in its entirety. Validation of Input: Accepting negative amounts for monthly rainfall data is not permitted.
use this code template to help you continue: private boolean included Indicates whether the item should be taken or not public Item(String name, double weight, int value) Initializes the Item’s fields to the values that are passed in; the included Field is initialized to false public Item(Item other) Initializes this item’s fields to the be the same as the other item’s public void setIncluded(boolean included) Setter for the item’s included field (you don’t need setters for the other fields) Given code: public class Item { private final String name; private final double weight; private final int value; public Item(String name, double weight, int value) { this.name = name; this.weight = weight; this.value = value; } static int max(int a, int b) { if(a > b) return a; return b; } // function to print the items which are taken static void printSelection(int W, Item[] items, int…
Exercise 6 - Loaded Coin Simulation Make a new class in the Lab2 project called LoadedCoinSim that simulates the toss of a loaded coin. A coin is loaded when it is constructed such that it is more likely to land on one value than another. Assume the probability the coin will land head is HEAD_PROB, and declare that as a constant in your program. Initially, use a value of 0.75, which means 75% chance the coin will show heads. Given this probability, simulate ten coin tosses and displaying the result. At the end, display the number of times the coin showed heads. The output should appear like this: Toss 1: HEADS Toss 2: HEADS Toss 3: HEADS Toss 4: TAILS Toss 5: HEADS Toss 6: HEADS Toss 7: HEADS Toss 8: HEADS Toss 9: TAILS Toss 10: HEADS Number of heads = 8
Create an automobile class that will be used by a dealership as a vehicle inventory program. The following attributes should be present in your automobile class: private string make private string model private string color private int year private int mileage Your program should have appropriate methods such as: default constructor parameterized constructor add a new vehicle method list vehicle information (return string array) remove a vehicle method update vehicle attributes method. All methods should include try..catch constructs. Except as noted all methods should return a success or failure message (failure message defined in "catch"). Create an additional class to call your automobile class (e.g., Main or AutomobileInventory). Include a try..catch construct and print it to the console. Call automobile class with parameterized constructor (e.g., "make, model, color, year, mileage"). Then call the method to list the values. Loop through the array and print to the screen.…
solve with java Create a class for Subject containing the Name of the subject and score of the subject. There should be following methods: set: it will take two arguments name and score, and set the values of the attributes. If score is less than 0 or greater than 100.0 then a message should be displayed “Incorrect score” and score should be set to Zero. set: it will take one double value as argument and set the value of score only. If score is less than 0 or greater than 100.0 then a message should be displayed “Incorrect score” and score should be set to Zero. display: it will display the name and score of the subject. Like “Name : Math, Score: 99.9” getScore: it will return the value of score. greaterThan: it will take subject’s object as argument, compare the calling object’s score with argument object’s score and return true if the calling object has greater score. Create a class “Main” having main method to perform following tasks. Create two objects of Subject class having…
Java - Access Specifiers Create a class named Circle that has attributes radius, area, and circumference and make the attributes private. Make a public method that sets the radius and a method that prints all attributes. Ask the user input for radius. Note: Use the PI from the math functions Inputs A line containing an integer 10 Sample Output Radius: 20 Area: 1256.64 Circumference: 125.66
A field has access that is somewhere between public and private. static final Opackage Oprotected
Design and implement a class called Car that contains instance data that represents the company, price, model, and year of the car. Define the Car constructor to initialize these values. Include getter and setter methods for all instance data, and a toString method that returns a one-line description of the car. Create a driver class called CarTest, whose main method instantiates array of Car objects and write the following methods: 1) Method “printInfo” that receives an array of cars and returns all information about all cars. 2) A Method called getTopByCompany that receives an array of Cars and then returns an array of cars containing the cars that have the highest price compared with cars from the same company.
True or FalseIt is a common practice to make all a class’s fields private and to provide access to those fields through methods.
Hints: • For each class, it is required to implement constructors, setters, getters, toString() method, and any other necessary method • If the user tries to do an operation that could violate the state of objects, the operation should be ignored and the application should display an error message (e.g. adding a passenger to the same trip twice, etc.) Checking equality of any 2 objects should be done via the equals() method • • Testing: After implementing the required classes, design and implement a testing class to test them as follows: There is a class that will do the main job of as follows: o It has one collection to store the whole data (all trips) o It has static methods, one for each operation happens frequently o For each adding or removing operation, a message should be displayed to the user to explain the status of the operation (i.e. if it was successful or not) • Create at least 7 trips in at least 3 different dates and add them to the collection that stores the whole data…