3. You can make a class abstract by declaring it with keyword abstract. An abstract classnormally contains none, one or more abstract methods. An abstract method is aninstance method with keyword abstract in its declaration.TrueFalseThe code will compile successfully when as long as a static method calls an instancemethod in the same class by using only the method name, and a static method triesto access an instance variable in the same class by using only the variable name.TrueFalse All the following statements about abstract methods are incorrect EXCEPT:We use abstract methods to define features by specifying the details.O All the methods in the subclasses must not be overloadedIf a single abstract method is abstract, the class may not be abstract.We can instantiate a class that has an abstract methodIf all abstract methods are overridden, the class is not concreteGiven classes Xyz and Abc (See Figure 401):public abstract class Xyz{public abstract void run();}public class Abc extends Xyz{@Overrideprotected void run() {}} // Figure 401Why does the Java compiler refuse to compile the program?Method run() in class Abc does not have any statements inside { and }, so shouldbe marked abstractMethod run() in class Abc must be marked publicMethod run() in class Abc must be marked privateO O O O

An abstract class is a class which can have 0 or more abstract methods An abstract class is declared…

You can make a class abstract by declaring it with keyword abstract. An abstract class normally contains none, one or more abstract methods. An abstract method is an instance method with keyword abstract in its declaration. True False

You can make a class abstract by declaring it with keyword abstract. An abstract class normally contains none, one or more abstract methods. An abstract method is an instance method with keyword abstract in its declaration. True False

Microsoft Visual C#

7th Edition

ISBN:9781337102100

Author:Joyce, Farrell.

Publisher:Joyce, Farrell.

Chapter10: Introduction To Inheritance

Section: Chapter Questions

Problem 20RQ

See similar textbooks

Similar questions

Write a complete program for the description given below. Consider a Billing class that implements an interface Payable having a method getTotalPayment Amount(). Besides this, you have a Doctor class with private instance variables (docID, docName, and docFee) and a public getDoc() method, Patient class with private instance variables (pName, pID. pDisease), Medicine class with private instance variables (medID, medName, medQty, medPrice), and Medical Test class with private instance variables (testID, testName, testPrice). Each of these classes has the toString() method to display the information of its object. The Billing class is having "Has A" relationship with the other four classes (Doctor, Patient, Medicine, and MedicalTest) mentioned above. The getPayment Amount() method of Billing class returns the total billing amount that includes doc fee, medicine cost, and medical test fee that a patient has to pay. After implementing these classes, you are required to do the following in…
All vehicles used for transportation in the U.S. must have identification, which varies according to the type of vehicle. For example, all automobiles have a unique Vehicle Identification Number (VIN) assigned by the manufacturer, plus a license plate number assigend by the state in which the auto is registerd. Modify the Auto class to include an instance variable for the license plate number. Implement the constructor so that an Auto can be constructed with a VIN and a license plate number. Override the getID() method to return the id of the auto as shown in this format: VIN=1234567890,plate=ABC123 (without any spaces). ** Represents an automobile.*/public class Auto // TODO: Inherit from Vehicle{ // TODO: Declare instance variables public Auto(String vin, String plate) { // TODO: Complete the constructor } // TODO: implement the getID() method for autos}
Write a java program that has:A class University that has:- Three private instance variables named firstName, lastName, and id- A constructor to initialize the three instance variables- A toString method to return: “Welcome,” + firstName +” “ + lastName + “Your ID is ” + id- AccessorsA subclass Employee that has:- Five additional private instance variables named department, rate, bonus, hours, and salary- An appropriate constructor to use constructor of superclass in defining those of the subclass- A method named compteSalary ( ) to return salary- A method named computeBonus ( ) to return bonus- Accessors A subclass Staff that:- Overrides computeBonus ( ) such that if hours are greater than 40, there will be %10 bonus for each additional houradded to salary- Overrides compteSalary ( ) such that salary = (rate * hours) + bonus- Overrides toString method to add department and salary into the outputA subclass Faculty that:- Overrides computeBonus ( ) such that if hours are greater than…
Write a class named Person with data attributes for a person’s name, address, and telephonenumber. Next, write a class named Customer that is a subclass of the Person class. TheCustomer class should have a data attribute for a customer number, and a Boolean data attributeindicating whether the customer wishes to be on a mailing list. Demonstrate an instance of theCustomer class in a simple program.
For this exercise, you are given a Team superclass with a BaseballTeam and FootballTeam subclass. Take a moment to examine these classes and the instance variables and methods in each. In the TeamTester class, you will see three objects declared and instantiated using the Team, FootballTeam, or BaseballTeam classes. For each object, use a print statement to print out any public method that returns information that is available for that particular object, including the toString. For example, the dolphin object is a FootballTeam object. One of the pieces of information that can be printed is the getTies() method, so you will call that method in your TeamTester file: System.out.println(dolphins.getTies()); Do this for all the methods that each of the objects can call. Hint: Remember, for the program to compile and run, Java looks for methods to exist in certain classes. ================================= public class Team { private String name;private String location;private int…
Consider this scenario, a mehtod in some class needs to access a data field in another class, here are two possible implementations: public class Process { /* * Check if student qualifies for financial help */ void check(Student student) { //.... } /* * Check if student qualifies for financial help */ void check(double studentGPA) { //.... }} In class Process, which check method you think is better, why? In other words, should we pass the object to the method or just the data member it needs? Disucuss the Pros and Cons of each approach (if any). Assume class Student has a mehod called getGPA( ).
Now we are going to use the design pattern for collecting objects. We are going to create two classes, a class AmazonOrder that models Amazon orders and a class Item that models items in Amazon orders. An item has a name and a price, and the name is unique. The Item class has a constructor that takes name and price, in that order. The class also has getters and setters for the instance variables. This is the design pattern for managing properties of objects. The setName() method should do nothing if the parameter is the empty string, and the setPrice() method should do nothing if the parameter is not positive. The class also has a toString() method that returns a string representation for the item in the format “Item[Name:iPad,Price:399.99]”. For simplicity, we assume an Amazon order can have at most 5 items, and class AmazonOrder has two instance variables, an array of Item with a length of 5 and an integer numOfItems to keep track of the number of items in the…
We have two classes, Person and Employee. Both have a field, firstName. We have instances of these objectsPerson p and Employee e. Both p and e have the same value for firstName, specifically, p.firstName = “joe”and e.firstName = “joe” Which of the following statements is necessarily true? Group of answer choices 1. p.equals(e) will return true because they contain the same firstName. 2. We don’t know if either class will have an equals method. 3. There is not enough information to tell what p.equals(e) will return. 4. p.equals(e) will return false but p == e will be true.
Which of the following are true? If we derive a class from an abstract class, we can select which methods we choose to implement in our derived class. Abstract classed cannot have concrete methods. We can declare an instance of an abstract class. All of the above statements are false.
Write a java program Write a class named Employee with name and salary as private data fields. Add a constructor with both parameters. Write a class named Manager which unherits the Employee class. Add an instance variable, named department, of type String and 15 private. Add a constructor in the subclass class and a toString () method that prints the manager's name, department, and salary [Hint: Add a tastanel) method in the super class as well]. Create objects of Manager and Employee dass
Say we have a collection of animal classes, with each class represents a kind of animal. They all share a common ability of “speak”. Dog speak in the way of “Woof! Woof!”, cats speak in the way of “Meow! Meow!”, etc. In order to capture this common characteristic, we need an interface named Speakable: public interface Speakable { // put the method header here } Think about what method is needed for the Speakable interface? (what method can describe the speakable feature? ) We simply need one method speak() to print out the way that the animal “speaks”. Put the method header in the interface body. This method does not take any parameter and does not return any value. Be reminded that you only need to put the method header with a semicolon (abstract method) into the interface. BE NOTED: Adding an interface is different from adding a class. You need to click File tab -> New -> Interface, to add an interface file to the project. Now download Cat.java. Have them implement the…
Say we have a collection of animal classes, with each class represents a kind of animal. They all share a common ability of “speak”. Dog speak in the way of “Woof! Woof!”, cats speak in the way of “Meow! Meow!”, etc. In order to capture this common characteristic, we need an interface named Speakable: public interface Speakable { // put the method header here } Think about what method is needed for the Speakable interface? (what method can describe the speakable feature? ) We simply need one method speak() to print out the way that the animal “speaks”. Put the method header in the interface body. This method does not take any parameter and does not return any value. Be reminded that you only need to put the method header with a semicolon (abstract method) into the interface. BE NOTED: Adding an interface is different from adding a class. You need to click File tab -> New -> Interface, to add an interface file to the project. Now download Dog.java. Have them implement the…