Objects First with Java: A Practical Introduction Using BlueJ (6th Edition)
6th Edition
ISBN: 9780134477367
Author: David J. Barnes, Michael Kolling
Publisher: PEARSON
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Textbook Question
Chapter 2, Problem 51E
Is it possible to remove the else part of the if-statement in the printTicket method (i.e., remove the word else and the block attached to it)? Try doing this and seeing if the code still compiles. What happens now if you try to print a ticket without inserting any money?
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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
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