ITEC 120 2007spring ibarland, jpittges

home—info—exams—lectures—labs—hws
Recipe—Laws—lies—syntax—java.lang docs—java.util docs

hw-ec04-backpack
extra credit homework: turning pockets into backpacks
hw-ec04; 15pts; Due Apr.20 (Fri) 17:00

Our current for code Explorer is a bit annoying, since there are exactly two pockets. We had lots of places where our code had nearly-repeated code (doing something once for the left-pocket, and then doing it again for the right-pocket).

Modify your Explorer so that it instead of being tied to exactly two Treasures, instead an Explorer has a knapsack, which can hold any number of Treasures (still subject to the weight limit). Go back an purge your code of any mentions of left- or right-pockets.

You'll find this change makes your code not only more powerful (Explorers can now carry 7000 Treasures, if they wanted to), but your it is also simpler and smaller less bug-prone. All hallmarks of a better design! Moreover, it gets rid of the need for lint — which really was just a way to keep from having fields which were uninitialized (which didn't hold a valid Treasure reference).

You'll need to update several methods. Note that inventory will love to make use of the method treasureListToString, needed for hw09. (You can turn in this homework before or after hw09.)

As always, each of the above steps should include unit tests, created with BlueJ's unit test tools.

A general note on extra-credit homeworks:

• They tend to be more work (point-for-point) than regular homeworks.
• They are not always as spelled out for you: sometimes you'll want/need to write a method or include a field even though the assignment doesn't explicitly say so.
• They should be fully polished: make sure the documentation really is descriptive, check for good grammar and spelling, etc.. Don't include fields/methods you never use. (All this applies to ordinary homeworks too, but we'll cut less slack for extra-credit homeworks.)

home—info—exams—lectures—labs—hws
Recipe—Laws—lies—syntax—java.lang docs—java.util docs

©2007, Ian Barland, Radford University Last modified 2007.Aug.27 (Mon)

Please mail any suggestions (incl. typos, broken links) to iba�rlandrad�ford.edu