CS 160 Lab 4

The objectives of this lab are to further acquaint you with the resources available to help you learn and to give you experience with many of the topics covered in Chapter 3 of your book.

To Do

Resources

Take a clean sheet of paper.   In the upper right corner put your name, your esus e-mail address, and your lab time.  Then answer the following questions.

What is your TA's name and the Consultants names (if you can't remember, don't be afraid to ask)? 

Bring up a browser and ....

Visit http://www.wiley.com/college/horstmann with your browser.  What is this site about?

Find the student resources on this site corresponding to your textbook. List the resources that are available to the student.

Programming (basic)

If you are among the many learners new to Java in CS 160, do this part.

Download the purse program found in chapter three of your book from the horstmann web site.  Create a new project in BlueJ named purse.  Copy the Purse and PurseTest classes into BlueJ classes of the same names (get rid of the outline stuff that BlueJ automatically puts into classes.  Compile and run this program.  Then do the following.

One

• Create a new instance field in class Purse for pennies.
• Modify the methods in class Purse so that you can also add pennies to the purse and get the proper value when asking for the contents of the purse.
• Modify the PurseTest main method to add 7 pennies to the purse.
• Compile and run the program
• Write the value on your paper that is printed.

Two

• Make a new constructor in class Purse that initializes the purse to contain a given number of pennies, nickels, dimes, and quarters.
• In the main method of PurseTest construct a new purse object that starts with 3 pennies, 5 nickels, 3 dimes, and 4 quarters.
• In the main method, of PurseTest, print the value of the coins in this new purse.
• Write the value on your paper that is printed.
• Then add statements to the main method of PurseTest that add 4 pennies, 1 nickel, 3 dimes, and 1 quarter to the new purse.
• Add another print statement to PurseTest to print the new value of the coins in the purse.
• Write the value on your paper that is printed.

Three

• Add lines at the end of method main in PurseTest to have the user type in input for pennies, nickels, dimes, and quarters, each of which is added to the current contents of the purse for pennies, nickels, dimes, and quarters, respectively.
• Be sure to import the JOptionsPane class (see page 110 in your book) on the first line of class PurseTest
• Be sure to include the line System.exit(0); at the end of method main
• Test your program with input 13, 7, 8, and 6 for pennies, nickels, dimes, and quarters, respectively.  Don't change previous lines in your program.  These input values should be added to what is in the purse already.

To Turn In

Turn your sheet in to the TA.  Then read the next paragraph.

If you get done with parts One through Three, use the rest of your time to review for the exam.  For example, you can do these exercises in your book: R31.R3.6, R3.8, and R3.16.  You can use the Windows built in calculator to check your results for R3.16 or write a simple class with a public static void main method to print the results of these expressions.  You may also ask the helpers other questions that you might have about Java in your review..

Programming (advanced)

If you are an advanced Java programmer or you just think the first exercise is too easy, do these two parts.

One

Exercises R31.R3.6, R3.8, and R3.16. You can use the Windows built in calculator to check your results for R3.16 or write a simple class with a public static void main method to print the results of these expressions.  In each case, write down the answer you get by hand, then write down the results against those obtained by using the calculator. If there is a difference, determine what the problem is.

Two

 Do exercise P3.17.  Use the advanced input method suggested in the book on page 113 to read in the year.