CMPT167 Lab0: Template Lab Write-up

Problem Statement:

Display a running total of a sequence of integers entered by the user.

Suitability:

This is quite a trivial problem, well within the reach of a calculator (or Google!). However, the solution does illustrate how the problem-solving process works, from problem statement to design to implementation.

Problem Restatement:

Given: A sequence of integers entered by the user
To Do: Calculate the sum of all integers entered thus far
Desired Result: Running total
Formula: (none applicable)

Libraries:

This program uses the basic Java libraries. It is coded as a Java applet, and so uses the applet libraries.

Problem Refinement (natural language pseudocode):

Input Section:
- user input value
Computation:
- calculate running total
Output:
- display running total

Second Refinement (natural language pseudocode):

Input
- Define a text input widget and bind it to the applet
- When the user presses enter, retrieve the value from the input widget and convert it to an integer
Computation
- Add the retrieved integer value to the running total
Output:
- Convert the integer running total to a string and set the status bar text accordingly (could also use a label widget)
- Clear the text input widget

Data Table:

number (int): the integer value entered by the user

sum (int): the integer running total

input (TextField): text input widget for number

(it is not necessary to include all widgets here (e.g., prompt -- see code), just the ones used for computation)

User Manual:

Description:

Addition is a trivial little applet that keeps a running total of integers entered by the user.

Operation:

There is just one text box in the applet window:

Enter integer and press Enter:

Type in an integer value and press Enter. It can be negative, but must not contain any decimal points, commas, or other non-numeric characters (letters, punctuation etc.).

Each time you type a number and press Enter, the status bar will be updated to show the current running total. Keep entering numbers to see the status bar change.

Test Cases, with expected results:

Put some effort into designing your test cases; QA is a challenging job! The idea is that if your program passes all the test cases, you'd be confident shipping it to a paying customer.

Normal Test case:

Enter integer and press Enter: 100
Enter integer and press Enter: -165
Enter integer and press Enter: 033
Status bar: -32

Test case that breaks (invalid input):

Enter integer and press Enter: -55
Enter integer and press Enter: 2.5
(Applet ignores input or crashes)

Screenshots

(Can be embedded here or left as separate files if you like, but list the filenames here.)

This write-up is done in HTML as a webpage, and this sample lab is done as a Java Applet. If you do this as well, you may opt to embed your applet directly into your lab write-up. But you should still have static screenshots in your write-up.