Lab 2: Basic Reading and Manipulation of User Input

Due Thursday, September 8 at 11:59 PM

Goals for This Lab

By the time you have completed this work, you should be able to:

• Be able to identify the type of expressions involving int and String
• Use string concatenation to create bigger strings from smaller strings and numbers
• Read in user input as integers (int) or strings (String)

• lab2questions.txt
• SquawkParrot.java
• PerimeterCalculation.java
• collaborators.txt

Step-by-Step Instructions

Step 1: Answer Questions Regarding Types

Download the lab2questions.txt file, and edit it with a text editor of your choice. Answer the questions in the file. Be sure to use the appropriate formatting. Save your work in your own local copy of lab2questions.txt. Be sure to preserve the filename and file type!

Step 2: Edit SquawkParrot.java

Download the SquawkParrot.java file, and open it in jGrasp (or a text editor of your choice). The file contains a program which is intended to behave very similarly to Parrot.java, except that it should print out some extra text before and after the user input. An example which illustrates this is shown below, with user input shown in bold:

Enter something to repeat: pretty bird
BRAAWK pretty bird!

Another example follows:

Enter something to repeat: apple
BRAAWK apple!

One more example:

Enter something to repeat: some words
BRAAWK some words!

You will need to use a variable to save exactly what the user typed in. You should only write a single System.out.println statement at the end of your code. With this in mind, you'll need to use string concatenation to create a big string to print (e.g., “BRAAWK pretty bird!” above), and then print it with a single System.out.println statement. Note that you will need a string which contains only a single character, namely “!” (the sentence you print ends with an exclamation point).

For full credit, the output of your program must match EXACTLY to the output shown above. That is, it should start with “BRAAWK”, followed by a space, followed by the user input, followed by an exclamation point.

Step 3: Edit PerimeterCalculation.java

For this task, you need to write a program that will calculate the perimeter of a rectangle. The user will give the program the width and height of the rectangle, and the program will print out the computed perimeter. An example which illustrates this is shown below, with user input shown in bold:

Enter width: 2
Enter height: 3
Perimeter: 10

In order to write this program, you will need to use variables to save the entered width and height values, Scanner to read integers, compute the result, and print the result with System.out.println. You will also need to use System.out.println to print the user prompts for width and height. As a hint, your code will look very similar to the AddTwo.java program from lecture.

For full credit, the output of your program must match EXACTLY to the output shown above.

Step 4: Turn in Your Solution Using Canvas

Log into Canvas, and go to the COMP 110 class. Click “Assignments” on the left pane, then click “Lab 2”. From here, you can upload your answers and your code. Specifically, you must turn in the following three files:

• lab2questions.txt
• SquawkParrot.java
• PerimeterCalculation.java

In addition, if you collaborated with anyone else, be sure to download collaborators.txt and write the names of the people you collaborated with in the file, one per line. Please submit this file along with the other three files.

You can turn in the assignment multiple times, but only the last version you submitted will be graded.