Objects First with Java: A Practical Introduction Using BlueJ (6th Edition)
6th Edition
ISBN: 9780134477367
Author: David J. Barnes, Michael Kolling
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 2, Problem 9E
Put back the word public, and then check whether it is possible to leave out the word class by trying to compile again. Make sure that both words are put back as they were originally before continuing.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Redefine the equals method of the class Date (Display 4.13) so that it hasa parameter of type Object and follows the other guidelines we gave for anequals method. (Remember, you should use getClass(), not instanceof.)
How about if the code only accepts "history", "language" and "PE", for the "class"? And, if they input a class that is not among the three, the string will return to "Error". How can we code it?
Implement your base class for the hierarchy from the previous exercise.
Chapter 2 Solutions
Objects First with Java: A Practical Introduction Using BlueJ (6th Edition)
Ch. 2 - Create a TicketMachine object on the object bench...Ch. 2 - What value is returned if you get the machine's...Ch. 2 - Prob. 3ECh. 2 - Prob. 4ECh. 2 - Create another ticket machine for tickets of a...Ch. 2 - Prob. 6ECh. 2 - Does it matter whether we write...Ch. 2 - Prob. 8ECh. 2 - Put back the word public, and then check whether...Ch. 2 - From your earlier experimentation with the ticket...
Ch. 2 - Prob. 11ECh. 2 - Prob. 12ECh. 2 - Prob. 13ECh. 2 - Prob. 14ECh. 2 - In the following field declaration from the...Ch. 2 - Prob. 16ECh. 2 - Prob. 17ECh. 2 - To what class does the following constructor...Ch. 2 - How many parameters does the following constructor...Ch. 2 - Prob. 20ECh. 2 - Suppose that the class Pet has a field called name...Ch. 2 - Challenge exercise The following object creation...Ch. 2 - Compare the header and body of the getBalance...Ch. 2 - If a call to getPrice can be characterized as...Ch. 2 - If the name of getBalance is changed to getAmount,...Ch. 2 - Prob. 26ECh. 2 - Try removing the return statement from the body of...Ch. 2 - Compare the method headers of getPrice and...Ch. 2 - Do the insertMoney and printTicket methods have...Ch. 2 - Create a ticket machine with a ticket price of...Ch. 2 - How can we tell from just its header that setPrice...Ch. 2 - Complete the body of the setPrice method so that...Ch. 2 - Prob. 33ECh. 2 - Is the increase method a mutator? If so, how could...Ch. 2 - Prob. 35ECh. 2 - Write down exactly what will be printed by the...Ch. 2 - Add a method called prompt to the TicketMachine...Ch. 2 - Prob. 38ECh. 2 - What about the following version?
Ch. 2 - Prob. 40ECh. 2 - Add a showPrice method to the TicketMachine class....Ch. 2 - Create two ticket machines with differently priced...Ch. 2 - Modify the constructor of TicketMachine so that it...Ch. 2 - Give the class two constructors. One should take a...Ch. 2 - Implement a method, empty, that simulates the...Ch. 2 - Prob. 46ECh. 2 - Predict what you think will happen if you change...Ch. 2 - Rewrite the if-else statement so that the method...Ch. 2 - Prob. 49ECh. 2 - In this version of printTicket, we also do...Ch. 2 - Is it possible to remove the else part of the...Ch. 2 - After a ticket has been printed, could the value...Ch. 2 - So far, we have introduced you to two arithmetic...Ch. 2 - Write an assignment statement that will store the...Ch. 2 - Write an assignment statement that will divide the...Ch. 2 - Prob. 56ECh. 2 - Modify your answer to the previous exercise so...Ch. 2 - Why does the following version of refundBalance...Ch. 2 - What happens if you try to compile the...Ch. 2 - What is wrong with the following version of the...Ch. 2 - Add a new method, emptyMachine, that is designed...Ch. 2 - Rewrite the printTicket method so that it declares...Ch. 2 - Challenge exercise Suppose we wished a single...Ch. 2 - List the name and return type of this method:
Ch. 2 - Prob. 65ECh. 2 - Write out the outer wrapping of a class called...Ch. 2 - Write out definitions for the following fields:
Ch. 2 - Write out a constructor for a class called Module....Ch. 2 - Prob. 69ECh. 2 - Correct the error in this method:...Ch. 2 - Write an accessor method called getName that...Ch. 2 - Write a mutator method called setAge that takes a...Ch. 2 - Write a method called printDetails for a class...Ch. 2 - Draw a picture of the form shown in Figure 2.3,...Ch. 2 - Prob. 75ECh. 2 - Create a Student with name "djb" and id "859012"....Ch. 2 - Prob. 77ECh. 2 - Challenge exercise Modify the getLoginName method...Ch. 2 - Consider the following expressions. Try to predict...Ch. 2 - Open the Code Pad in the better-ticket-machine...Ch. 2 - Now add the following in the Code Pad:...Ch. 2 - Add the following: t1.InsertMoney500; What would...Ch. 2 - Prob. 83ECh. 2 - Prob. 84ECh. 2 - Add a field, pages, to the Book class to store the...Ch. 2 - Are the Book objects you have implemented...Ch. 2 - Add a method, printDetails, to the Book class....Ch. 2 - Add a further field, refNumber, to the Book class....Ch. 2 - Modify your printDetai 1 s method to include...Ch. 2 - Prob. 90ECh. 2 - Add a further integer field, borrowed, to the Book...Ch. 2 - Prob. 92ECh. 2 - Prob. 93ECh. 2 - Prob. 94E
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
Open the Chap3\ Error3\ Error3 project from the student sample programs folder. The btnCalculate Click procedur...
Starting Out With Visual Basic (8th Edition)
Given that y=ax3+7, which of the following are correct Java statements for this equations? int y = a x x (x +...
Java How to Program, Early Objects (11th Edition) (Deitel: How to Program)
The _________ library functionreturns the remainder of a floating-point division.
Starting Out with C++ from Control Structures to Objects (9th Edition)
Find the no-load value of υo in the circuit shown.
Find υo when RL is 150 Ω.
How much power is dissipated in th...
Electric Circuits. (11th Edition)
Create a class RoomOccupancy that can be used to record the number of people in the rooms of a building. The cl...
Java: An Introduction to Problem Solving and Programming (8th Edition)
Look at the following interface: public interface Computable { double compute(double x); } Write a statement th...
Starting Out with Java: From Control Structures through Data Structures (4th Edition) (What's New in Computer Science)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.Similar questions
- Iterating over a collection of items is the job of the for construct's looping mechanism. So long as there are things to process, it will keep running forever. So, what do you make of this?arrow_forwardRead the class Person to store the name a person we discuss in the class (source is Person.java attached in the assignment). As we can see that the methods we included merely set the name and print the name of a person. Redefine the class person so that, in addition to what existing Class does, you can Set the last name only. Set the first name only. Set the middle name. Check whether a given last name is the same as the last name of this person. Check whether a give first name is the same as the first name of this person. Check whether a given middle name is the same as the middle name of this person. Add the method equals that returns true if two objects contains the same first and last name. Add the method makeCopy that copies the instance of variables of a Person object into another Person object. Add the method getCopy that creates and returns the address of the object, which is a copy of another Person Object. Write the definition of the methods of the class Person to implement…arrow_forwardCreate the compareTo method for a class that represents an individual whose first and last names are stored as two Strings. In an alphabetical list of people with last names first and then first names, one individual is "less than" another if they come before the other.(as is typical).arrow_forward
- do the following question in javaarrow_forwardOne last implementation, can you have the user implement their own names and employee info (like first and last name, # of hours worked, hourly rate, and their major) and it computes it for them and prints it out?arrow_forwardwrite the code in java. Write the class Student having attributes name (String), age (int) and cgpa (double) and methods to set the values of attributes and to return them. There should be constructors (default, parameterize and copy) to initialize the value of attributes. Write another class name Student Management having array of students and count of students as attribute. There should be method for the following: 1. Add new Student in Array 2. Remove a Student from Array using Name (of Student) 3. Sort the Students in array using Name (ascending order) 4. Sort the Students in array using Age (ascending order) 5. Sort the Students in array using CGPA (ascending order) 6. Reverse the order of the Students in array 7. Display information of all Students in array (from zero index to last index) Write another class named as Main having main method and show activity of above methods. 1. Add 5 Students in array 2. Display all students in array 3. Remove a student by name 4. Show the count…arrow_forward
- For this exercise, we are going to do a variation on our Student class by looking at a StudentTest class. The StudentTest class stores math and ELA test scores for a student. We will then extend this class in the HSStudent class, which will check the math and ELA scores to determine if the student has passed. Combined with service hours, the HSStudent class will also check to see if the student has qualified for graduation. Details for each class are outlined in the starter code for each class. In the StudentTester class, you will prompt the user for test scores and service hours, then use these to create a HSStudent object. After creating the object, print out the results. Please enter the student name: Ryan Please enter the Math Score: 500 Please enter the ELA Score: 600 Please enter the Service Hours: 100 Pass Math? false Pass ELA? true Completed Service Hours? true Ryan has not yet qualified for graduation. import java.util.Scanner; public class StudentTester{public static…arrow_forwardImplement the Solver class. In doing so, you are allowed to define other classes to help you (as well as use “built-in” Java classes or the book’s classes). The point of the solver class is the solve method which takes a board/puzzle configuration represented as a 2D array of booleans and returns a char array containing a minimal sequence of moves that will lead to the solved board (all the cells around the edges being filled). The board configuration is passed in as a 5-by-5 boolean array of Booleans with exactly 16 true cells (filled) and 9 false cells (empty). The solve method then returns an array of characters representing a minimal sequence of moves that solves the puzzle. In other words, if the characters from the returned array are used in order as input to the move method on the Board object representing the initial configuration, the resulting board configuration represents the solved board. Furthermore, the solution must be minimal in the sense that there are no solutions…arrow_forwardImplement the Solver class. In doing so, you are allowed to define other classes to help you (as well as use “built-in” Java classes or the book’s classes). The point of the solver class is the solve method which takes a board/puzzle configuration represented as a 2D array of booleans and returns a char array containing a minimal sequence of moves that will lead to the solved board (all the cells around the edges being filled). The board configuration is passed in as a 5-by-5 boolean array of Booleans with exactly 16 true cells (filled) and 9 false cells (empty). The solve method then returns an array of characters representing a minimal sequence of moves that solves the puzzle. In other words, if the characters from the returned array are used in order as input to the move method on the Board object representing the initial configuration, the resulting board configuration represents the solved board. Furthermore, the solution must be minimal in the sense that there are no solutions…arrow_forward
- Implement the Solver class. In doing so, you are allowed to define other classes to help you (as well as use “built-in” Java classes or the book’s classes). The point of the solver class is the solve method which takes a board/puzzle configuration represented as a 2D array of booleans and returns a char array containing a minimal sequence of moves that will lead to the solved board (all the cells around the edges being filled). The board configuration is passed in as a 5-by-5 boolean array of Booleans with exactly 16 true cells (filled) and 9 false cells (empty). The solve method then returns an array of characters representing a minimal sequence of moves that solves the puzzle. In other words, if the characters from the returned array are used in order as input to the move method on the Board object representing the initial configuration, the resulting board configuration represents the solved board. Furthermore, the solution must be minimal in the sense that there are no solutions…arrow_forwardNot all dogs like to bark, but some like to make a lot of noise! In this exercise we have a Dog superclass and a LoudDog subclass. You do not need to modify the Dog class. Your task is to write two override methods in the LoudDog class. You will override the speak method to return BARK!. You will then override the toString so that it returns Clover is loud and likes to BARK! where Clover is replaced by the name variable. Create and print at least one Dog and one LoudDog to test. public class DogTester{public static void main(String[] args){// Start here}} public class Dog{private String name;public Dog(String name){this.name = name;}public String getName(){return name;}public String speak(){return "Bark!";}public String toString(){return name + " likes to " + speak();}} public class LoudDog extends Dog{public LoudDog(String name){super(name);}// Override the speak method here//Override the toString here.//Remember, you can access the name using super.getName()}arrow_forwardadd 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.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Database System ConceptsComputer ScienceISBN:9780078022159Author:Abraham Silberschatz Professor, Henry F. Korth, S. SudarshanPublisher:McGraw-Hill EducationStarting Out with Python (4th Edition)Computer ScienceISBN:9780134444321Author:Tony GaddisPublisher:PEARSONDigital Fundamentals (11th Edition)Computer ScienceISBN:9780132737968Author:Thomas L. FloydPublisher:PEARSON
- C How to Program (8th Edition)Computer ScienceISBN:9780133976892Author:Paul J. Deitel, Harvey DeitelPublisher:PEARSONDatabase Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781337627900Author:Carlos Coronel, Steven MorrisPublisher:Cengage LearningProgrammable Logic ControllersComputer ScienceISBN:9780073373843Author:Frank D. PetruzellaPublisher:McGraw-Hill Education
Database System Concepts
Computer Science
ISBN:9780078022159
Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:McGraw-Hill Education
Starting Out with Python (4th Edition)
Computer Science
ISBN:9780134444321
Author:Tony Gaddis
Publisher:PEARSON
Digital Fundamentals (11th Edition)
Computer Science
ISBN:9780132737968
Author:Thomas L. Floyd
Publisher:PEARSON
C How to Program (8th Edition)
Computer Science
ISBN:9780133976892
Author:Paul J. Deitel, Harvey Deitel
Publisher:PEARSON
Database Systems: Design, Implementation, & Manag...
Computer Science
ISBN:9781337627900
Author:Carlos Coronel, Steven Morris
Publisher:Cengage Learning
Programmable Logic Controllers
Computer Science
ISBN:9780073373843
Author:Frank D. Petruzella
Publisher:McGraw-Hill Education
Java Math Library; Author: Alex Lee;https://www.youtube.com/watch?v=ufegX5o8uc4;License: Standard YouTube License, CC-BY