Java: An Introduction to Problem Solving and Programming (8th Edition)
8th Edition
ISBN: 9780134462035
Author: Walter Savitch
Publisher: PEARSON
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Textbook Question
Chapter 6, Problem 8E
Sometimes we would like a class that has just a single unique instance. Create a class Merlin that has one attribute, theWizard, which is static and of type Merlin. The class has only one constructor and two methods, as follows:
- Merlin—a private constructor. Only this class can invoke this constructor; no other class or
program can create an instance of Merlin. - summon—a static method that returns theWizard if it is not null; if theWizard is null, this method creates an instance of Merlin using the private constructor and assigns it to theWizard before returning it.
- consull—a non-static method that returns the string “Full the sword from the stone”.
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Chapter 6 Solutions
Java: An Introduction to Problem Solving and Programming (8th Edition)
Ch. 6.1 - If a class is named Student, what name can you use...Ch. 6.1 - When defining a constructor, what do you specify...Ch. 6.1 - What is a default constructor?Ch. 6.1 - Does every class in Java automatically have a...Ch. 6.1 - In the program PetDemo shown in Listing 6 2, you...Ch. 6.2 - Prob. 6STQCh. 6.2 - Can a class contain both instance variables and...Ch. 6.2 - Can you reference a static variable by name within...Ch. 6.2 - Can you reference an instance variable by name...Ch. 6.2 - Can you reference a static variable by name within...
Ch. 6.2 - Can you reference an instance variable by name...Ch. 6.2 - Is the following valid, given the class...Ch. 6.2 - Prob. 13STQCh. 6.2 - Prob. 14STQCh. 6.2 - Prob. 15STQCh. 6.2 - Is the following valid, given the class...Ch. 6.2 - What values are returned by each of the following?...Ch. 6.2 - Suppose that speed is a variable of type double...Ch. 6.2 - Repeat the previous question, but instead assign...Ch. 6.2 - Suppose that nl is of type int and n2 is of type...Ch. 6.2 - Define a class CircleCalculator that hat only two...Ch. 6.2 - Which of the following statements are legal?...Ch. 6.2 - Write a Java expression to convert the number in...Ch. 6.2 - Consider the variable 5 of type String that...Ch. 6.2 - Repeat the previous question, but accommodate a...Ch. 6.2 - Write Java code to display the largest and...Ch. 6.3 - Prob. 27STQCh. 6.3 - Consider the variable allCents in the method...Ch. 6.3 - What is wrong with a program that starts as...Ch. 6.3 - Prob. 30STQCh. 6.3 - In your definition of the class OutputFormat. In...Ch. 6.4 - Prob. 32STQCh. 6.4 - Prob. 33STQCh. 6.4 - Prob. 34STQCh. 6.4 - Consider the class Species in Listing 5.19 of...Ch. 6.4 - Repeat the previous question for a method...Ch. 6.4 - Still considering the class Species in Listing...Ch. 6.4 - Rewrite the method add in Listing 6.16 so that it...Ch. 6.4 - In Listing 6.16, the set method that has a String...Ch. 6.5 - Give the definitions of three accessor methods...Ch. 6.6 - If cardSuit is an instance of Suit and is assigned...Ch. 6.7 - Suppose you want to use classes in the package...Ch. 6.7 - Prob. 43STQCh. 6.7 - Can a package have any name you might want, or are...Ch. 6.7 - On your system, place the class Pet (Listing 6.1)...Ch. 6.8 - The previous section showed you how to change the...Ch. 6 - Prob. 1ECh. 6 - Prob. 2ECh. 6 - Write a default constructor and a second...Ch. 6 - Write a constructor for the class...Ch. 6 - Consider a class characteristic that will be used...Ch. 6 - Create a class RoomOccupancy that can be used to...Ch. 6 - Write a program that tests the class RoomOccupancy...Ch. 6 - Sometimes we would like a class that has just a...Ch. 6 - Create a program that tests the class Merlin...Ch. 6 - In the previous chapter, Self-Test Question 16...Ch. 6 - Create a class Android whose objects have unique...Ch. 6 - Prob. 12ECh. 6 - Modify the definition of the class Species in...Ch. 6 - Prob. 2PCh. 6 - Using the class Pet from Listing 6.1, write a...Ch. 6 - Do Practice Program 4 from Chapter 5 except define...Ch. 6 - The following class displays a disclaimer every...Ch. 6 - Do Practice Program 5 from Chapter 5 but add a...Ch. 6 - We can improve the Beer class from the previous...Ch. 6 - Define a utility class for displaying values of...Ch. 6 - Write a new class TruncatedDollarFormat that is...Ch. 6 - Complete and fully test the class Time that...Ch. 6 - Complete and fully test the class Characteristic...Ch. 6 - Write a Java enumeration LetterGrade that...Ch. 6 - Complete and fully test the class Per n that...Ch. 6 - Write a Temperature class that represents...Ch. 6 - Repeat Programming Project 8 of the previous...Ch. 6 - Write and fully test a class that represents...Ch. 6 - Write a program that will record the votes for one...Ch. 6 - Repeat Programming Project 10 from Chapter 5, but...Ch. 6 - Create a JavaFX application that displays a button...
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