ICS 121 Spring 2004

Instructor: Robbins

Assignment 6

Due: Tuesday, May 18 in Distribution Center

1. Estimation (1 point)

Effort estimation is the practice of making accurate estimates of how long it will take to complete a piece of work. Software developers are notoriously bad at this. You will practice by estimating how long it takes you to complete a task.

Calculate the error percentage: ((YOUR ACTUAL) - (YOUR ESTIMATE)) / (YOUR ESTIMATE)

TYPE YOUR ERROR PERCENTAGE HERE

The following questions relate to this description of a wrist watch. (Note: this example is much simpler than real watch instuctions.)

2. Decision table (4 points)

The following decision table uses headings to consider all combinations of the state of each feature of the wrist watch. Fill in each cell with a precise description of the contents of the watch display in the specified situation.

Display Mode	Timer state	Alarm state	Myster Q/A	Watch Display Contents
dont care	dont care	Ringing	dont care	ENTER DESCRIPTION HERE
TimeDate	dont care	Enabled	dont care	ENTER DESCRIPTION HERE
TimeDate	dont care	Disabled	dont care	ENTER DESCRIPTION HERE
AlarmSet	dont care	Enabled	dont care	ENTER DESCRIPTION HERE
AlarmSet	dont care	Disabled	dont care	ENTER DESCRIPTION HERE
Timer	Stopped	dont care	dont care	ENTER DESCRIPTION HERE
Timer	Running	dont care	dont care	ENTER DESCRIPTION HERE
MysteryAnswer	dont care	dont care	Question	ENTER DESCRIPTION HERE
MysteryAnswer	dont care	dont care	Answer	ENTER DESCRIPTION HERE

3. UI Design Mockup (6 points)

Follow the HTML mockup method described here to build a mockup of the watch user interface. Perform steps 1, 2, and 3 only. Your result will be one long HTML page with HR tags dividing each logical screen. Define one HTML anchor for each logical screen. Add HTML links for each important event and/or condition that can happen on each logical screen. Each HTML link should go to a suitable destination screen.

HTML links are not visible on a printout. So, to make it possible for the TA to grade your printouts, please number each logical screen and include the number of the destination screen in each link label. E.g., rather than using the label mode button, instead use mode button (5), if it linked to your 5th logical screen.

USE A TEXT EDITOR TO MAKE AN HTML MOCKUP, PRINT IT, AND STAPLE IT TO THESE PAGES.

4. UML State Diagram (6 points)

Draw a UML state diagram for the watch modes. Specifically, model each watch function and the way that a user can navigate between functions. Use concurrent states for aspects of the watch state that can vary indpendently: e.g., the alarm mode states are independent of the timer mode states.

Notes:

• Do not model each mystery answer with its own states, that will be too complicated and hard-coded.
• Make sure to handle concurrent and composite states properly.
• This state diagram will be more complex than your last assignment.

USE ArgoUML, Gentleware Poseidon OR Rational Rose TO MAKE A DIAGRAM, PRINT IT, AND STAPLE IT TO THESE PAGES. Note: if you use ArgoUML, you cannot draw concurrent substates, so use fork and join pseudostates instead.

5. Reading: Fowler chapter 4 (3 points)

Which of the following describe UML sequence diagrams. Delete the bullets that are incorrect, leaving only true statements in the list.

• Each participant in a sequence diagram is drawn as a box at the very top of the page.
• Sequence diagrams are a good way to show interactions between objects.
• The length of an activation box indicates the amount of time that the CPU is excecuting statements in that method.
• Complex algorithms are can be more clear in pseudocode than in sequence diagrams.
• Guards are conditions that control whether a message is sent or not.
• Solid lines with solid arrows are method calls whenever they point to the right, and returns whenever they point to the left.