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 4, Problem 49E
Add a getUnsold method to the Auction class with the following header:
This method should iterate over the lots field, storing unsold lots in a new ArrayList local variable. What you are looking for is Lot objects whose highestBid field Is null. At the end of the method, return the list of unsold lots.
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Define a class called Book. This class should store attributes such as the title, ISBN number, author, edition, publisher, and year of publication. Provide get/set methods in this class to access these attributes. Define a class called Bookshelf, which contains the main method. This class should create a few book objects with distinct names and store them in an ArrayList. This class should then list the names of all books in the ArrayList. Enhance the program by providing a sort function, which will sort the books in ascending order of their year of publication. Create a few more Bookobjects with the same names but with different edition numbers, ISBNs, and years of publication. Add these new Book objects to the ArrayList, and display the book list sorted by book name; for duplicate books of the same name, sort the list by year of publication. (Hint: You will need to define a comparator class that takes two Book objects as parameters of the compareTo This method should do a two-step…
Library class:
Fields: books as arraylist to store all the books available in the library
B3
B1
B2
В4
B5
Constructor:
Library()
}
: No parameterized constructor to create the books object
Methods:
1. addBook(Book bookobj): to add a new book to the arraylist; send the book object as a
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2. searchBook(String name): search a book by a given name in the arraylist. if exits print
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3. RemoveBook(String name): to delete a book object from arraylist by a given name:
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Book class:
Fileds: bookld, bookname.
Constructor: two parameterized constructor that accepts name
a parameter
Book(int ID, String name)
.....
Methods:
1. Accessor method to return the name of the book
2. Mutator method to change the id of the book.
Use this Main method: in your program:
public static void main(String args[])
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Library lib=new Library();
lib.addBook(new Book("b1"));
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Observer pattern
The PhoneModel class stores a phone number as a list of digits, and the Keypad class has this method:
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The Screen wants to respond to each key being entered.
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The first observer prints the newest digit out to the screen
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Chapter 4 Solutions
Objects First with Java: A Practical Introduction Using BlueJ (6th Edition)
Ch. 4 - Prob. 1ECh. 4 - What happens if you create a new MusicOrganizer...Ch. 4 - Prob. 3ECh. 4 - Prob. 4ECh. 4 - Write a declaration of a local variable called...Ch. 4 - Prob. 6ECh. 4 - Write assignments to the library, cs101. and track...Ch. 4 - If a collection stores 10 objects, what value...Ch. 4 - Write a method call using get to return the fifth...Ch. 4 - Prob. 10E
Ch. 4 - Write a method call to add the object held in the...Ch. 4 - Write a method call to remove the third object...Ch. 4 - Suppose that an object is stored at index 6 in a...Ch. 4 - Add a method called checklndex to the...Ch. 4 - Write an alternative version of checkIndex called...Ch. 4 - Rewrite both the 1istFi1e and removeFi1e methods...Ch. 4 - Prob. 17ECh. 4 - Prob. 18ECh. 4 - We know that the first file name is stored at...Ch. 4 - Prob. 20ECh. 4 - Create a MusicOrganizer and store a few file names...Ch. 4 - Create an ArrayList<String> in the Code Pad by...Ch. 4 - If you wish, you could use the debugger to help...Ch. 4 - Challenge exercise The for-each loop does not use...Ch. 4 - Prob. 25ECh. 4 - Prob. 26ECh. 4 - Prob. 27ECh. 4 - Write out the header of a for-each loop to process...Ch. 4 - Suppose we express the first version of the key...Ch. 4 - Write a while loop (for example, in a method...Ch. 4 - Write a while loop to add up the values 1 to 10...Ch. 4 - Write a method called sum with a while loop that...Ch. 4 - Challenge exercise Write a method isPrime (int n)...Ch. 4 - In the findFirst method, the loop's condition...Ch. 4 - Prob. 35ECh. 4 - Have the MusicOrganizer increment the play count...Ch. 4 - Prob. 37ECh. 4 - Prob. 38ECh. 4 - Prob. 39ECh. 4 - Prob. 40ECh. 4 - Complete the numberOfMembers method to return the...Ch. 4 - Prob. 42ECh. 4 - Prob. 43ECh. 4 - Prob. 44ECh. 4 - Challenge exercise Write a method to play every...Ch. 4 - Prob. 46ECh. 4 - Prob. 47ECh. 4 - Add a close method to the Auction class. This...Ch. 4 - Add a getUnsold method to the Auction class with...Ch. 4 - Suppose the Auction class includes a method that...Ch. 4 - Rewrite getLot so that it does not rely on a lot...Ch. 4 - Prob. 52ECh. 4 - Prob. 53ECh. 4 - Prob. 54ECh. 4 - Prob. 55ECh. 4 - Open the products project and complete the...Ch. 4 - Implement the findProduct method. This should look...Ch. 4 - Implement the numberInStock method. This should...Ch. 4 - Prob. 59ECh. 4 - Challenge exercise Implement a method in...Ch. 4 - Java provides another type of loop: the do-while...Ch. 4 - Prob. 85ECh. 4 - Prob. 86ECh. 4 - Find out about Java's switch-case statement. What...
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