CS 149 Algorithm Development
Lab04A: Submitting Your Program through WebCAT

Background

Objectives

• Be able to login to WebCAT
• Be able to submit programs and receive feedback through WebCAT
• Know how to write Java programs that:
• Read values from the keyboard (standard input).
• Use integer division and remainder
• Display results with appropriate labels

Key Terms

Scanner 

class with methods that return tokens from an input stream

return value

The value a method sends back to the caller at the completion of the method execution

instantiate

The process of creating a new instance of an class (i.e., an object)

integer division(/) and remainder(%)

Binary operations that perform integer division (/ produces the quotient, % produces the remainder)

import statements

Statements in a java program that make available classes from the standard java packages

Materials Needed

• Enrollment in the class (for CANVAS and WebCAT)
• Textbook
• Algorithm and examples developed from class on Friday.
  

• Review your algorithms for solving the following problem. Indicate the names of all required containers, and list all required steps in the conversion.
  (Note: You may have been assigned this task as homework prior to the lab.)
  
  Requirements: A user needs to convert a seconds counter into hours:minutes:seconds format, representing the equivalent number of whole hours and the residual minutes and seconds.
  
  For example:
  

  Input	Output
  Seconds Counter	Hours	Minutes	Seconds
  5000	1	23	20
  3625	1	0	25
  1000	0	16	40

  
  Write the algorithm to make this conversion. Identify conversion factors as constants, and to identify the required containers for input and output variables.
  
  As you develop the algorithm, think about problem solving in general. First, make sure that you know how to do this task on paper. Then you can begin to think about how to describe the process algorithmically.
  
  

• Create a new program, SecondsToHours.java, using the following structure.

1. Create the heading using the Javadocs format found in the accompanying program template. Save this file as SecondsToHours.java. Alter the comments and class name appropriately.
2. Add an import statement to make Scanner available to your program. (import java.util.Scanner;) Review Thursday's lab for an example of using the Scanner.
3. Create the class declaration and the main method declarations. Don't forget the braces to enclose the associated code.
4. Add all required constant and variable declarations at the start of the main method. Look at your algorithm and declare all of your containers. You should have constants to define the number of seconds per hour and minute.
   
5. Declare your Scanner variable with the other declarations. You will need to instantiate a Scanner object passing it System.in. (see Gaddis, Section 2.13)
   
6. Next, build a prompt for the input (See below), then read the seconds using your Scanner variable and an appropriate next method. Refer to your book for an appropriate method to use.
   
   The input prompt should be "Enter the number of seconds: ", exactly. Notice the space directly following the colon. Use the print method rather than a println method so that the cursor remains on the same line as the prompt. (Any deviation from this specification will cause your program to be flagged as incorrect.)
   
   
7. Calculate the equivalent hours, minutes, and seconds using your algorithm.
8. Finally, output the your result.
   
   The program output must be very specific. Use the following format, filling in the blanks with the appropriate input and output values.
   
   (blank line)
   _____ seconds  =   __ hours, ___ minutes, and ___ seconds
   
   For example:
   
   1000 seconds = 0 hours, 16 minutes, and 40 seconds
   
   Include spaces around each of the values. There should be exactly one space between elements on the output line, and no leading or trailing spaces. Be sure to include the blank lines in the output (either using a "\n" character or System.out.println(). Incorrect spacing or anything other than two lines of output (each with one newline character at the end) will cause the program to be flagged as incorrect. Remember that System.out.println(...) generates one newline character automatically.
   

• Test your program with several input values, and make corrections if the output is not correct.
  

Part 3: Submitting Your Work Through WebCAT

• SEE DEMO BEFORE STARTING THIS STEP

• Submit your program for grading by following these steps
1. Open a console window, and navigate to your working directory (where the Java files are).
   
   
2. Create a new zip file containing the two Java files:
   
   zip lab2b.zip SecondsToHours.java

   Alternately, "lasso" the two files in File Browser and right click. Choose to compress and then choose the .zip format.

3. Login to WebCat (webcat.cs.jmu.edu), if you aren't logged in already. (Your password is the last four digits of your student ID number.)
   
   
4. Click the "Submit" button next to the assignment "Lab04A".
    
5. Browse to the zip file that was created above, then click "Upload Submission".
    
6. Confirm that the correct files were uploaded (and click "Confirm").
    
7. Wait for the Submission Results report to appear.
   
   
• Interpreting the Submission Results report:
  
  If the program is correct, you'll see a score summary at the top of the page indicating 50/50 points for Correctness/Testing. The Design/Readability Score will be added later by the instructor.
  
  If the Code Coverage from Your Tests is not 100%, then you have an error in your program. The output that it is generating is not what was specified. You will need to check the specifications again, and revise your program.
  
  

  Correct Program	Incorrect Program