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 60E
Challenge exercise Implement a method in StockManager to print details of all products with stock levels below a given value (passed as a parameter to the method).
Modify the addProduct method so that a new product cannot be added to the product list with the same ID as an existing one.
Add to StockManager a method that finds a product from its name rather than its ID:
public Product findProduct (String name)
In order to do this, you need to know that two String objects, s1 and s2, can be tested for equality with the boolean expression
S1. equals (s2)
More details about comparing Strings can be found in Chapter 6.
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c. Using the information from part b, prepare a network diagram. Identify the critical path.
2. UNIX Shell and History Feature [20 points]
This question consists of designing a C program to serve as a shell interface that
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shell interface gives the user a prompt, after which the next command is entered.
The example below illustrates the prompt osh> and the user's next command:
cat prog.c. The UNIX/Linux cat command displays the contents of the file
prog.c on the terminal using the UNIX/Linux cat command and your program
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osh> cat prog.c
The above can be achieved by running your shell interface as a parent process.
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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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