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CSCI $1302$ Programming Principles II

Georgia Southern University

Department of Computer Science

Fall $2024$

Lab $3$

Point Value: $20$ points

Due: Friday August $30,2024,$ end of lab

Objectives

$1.$ Update an existing class to explore aggregation and composition.

$2.$ Review UML language and documentation.

$3.$ Use debugging techniques to debug and correct code.

$4.$ Use the IDE$$s built$-$in debugger to debug and correct code.

$5.$ Archive Java source code files and other documents into a zip file.

Description

Complete the following steps as described and upload requested materials to Folio in the

appropriate Dropbox in a single zip file. Submit Java source code files to Gradescope.

$$ Students should work in groups of two for this lab. When submitting your zip file, fill out

the comment header and indicate both group member names. On Gradescope, you can

choose to add a group member, once one person has submitted the code file, must be

done to every submission.

$$ Your submitted zip file should be named Lab#LastName$1$LastName$2.$zip. For instance,

Lab$3$JonesSmith. Any requested screenshots and$/$or answers to questions should be

included in a separate Word document.

$$ All programs should have a comment header. That comment header should

include information similar to:

$/**$

$*$ File: PAssign$0.$java

$*$ Class: CSCI $1302$

$*$ Author: Christopher Williams

$*$ Created on: Jun $6,2016$

$*$ Last Modified: Aug $16,2018$

$*$ Description: Display three messages to the console

$*/$

$$ Before writing any code, for each problem, discuss with your partner how you plan to

approach solving the given problem. Once you both agree on a way to attempt the

problem, only then should code be written.

$$ Pay attention to names and any other requested material. Failure to include material

will result in the loss of points as described below.

$2$

Lab Problems

For all problems, use inline comments to describe major actions. Ask for assistance if needed.

NOTE: For this lab, you will be using the WaterBottle class and test program provided in Folio.

You will need to modify the test program to test the new classes you will be building.

Look for the TODO comments and delete each comment when you complete it$.$ These show up

in Eclipse in the $$Tasks$$ tab: Windows $->$ Show View $->$ Tasks.

$1.$ Composed$/$Aggregated Objects $$ Create a new class named LunchBag. LunchBag should

have data members of length, width, height, and a water bottle. All LunchBags have a bottle

holder that can hold a WaterBottle that can be purchased separately from the LunchBag $($so

it can be created in a main method and passed to the LunchBag class$).$

Additional Requirements

a$)$ A default LunchBag should have dimensions of $11\mathrm{.}2$L x $6\mathrm{.}1$W x $7\mathrm{.}9$H$.$

b$)$ There should be a default constructor that sets default values for the LunchBag. Create

a default WaterBottle in this constructor: setWaterBottle$($new WaterBottle$())$;$.$

c$)$ There should be a convenience constructor that takes four parameters that match all

data members in the order they are listed in the description above.

d$)$ All LunchBag data members should have an accessor and a mutator and all values

should be positive. If they are not positive, set them to their default values.

$$ This includes the WaterBottle data member which should also have an accessor

and a mutator.

e$)$ A LunchBag can hold a WaterBottle as long as the diameter is positive and less than or

equal to $4.$

$$ If a WaterBottle is set using the appropriate mutator method, an error message

should be printed if the WaterBottle cannot be stored and a default WaterBottle

should be used in its place.

$$ Note that an error message in the mutator is not the most appropriate

way to accomplish this. In Chapter $12,$ we will learn the correct way.

$$ Submit both your WaterBottle and LunchBag classes to Gradescope.

$2.$ Composed$/$Aggregated Objects $$ Create a new class named LunchBox. LunchBox should

have data members of length, width, and a water bottle. All LunchBoxs come with an

included WaterBottle that is manufactured at the same time as the LunchBox and cannot be

replaced with off$-$the$-$shelf WaterBottles $($we have no way of preventing this at the moment

because users will have access to the accessor method $($similar to the immutable example in

the slides$)).$

Additional Requirements

a$)$ A default LunchBox should have dimensions of $10\mathrm{.}6$L x $7\mathrm{.}7$W x $6\mathrm{.}33$H$.$

b$)$ The default WaterBottle that comes with the LunchBox is $4\mathrm{.}0$H and $0\mathrm{.}9$R$.$

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o As a composed object, this should be created at the same time as the LunchBox.

c$)$ There should be a default constructor that sets default values for the LunchBox and

instantiates the WaterBottle with the correct dimensions as a composed object.

d$)$ There should be a convenience constructor that takes four parameters that match all

data members in the order they are listed above.

e$)$ All LunchBox data members should have an accessor and a mutator and all values

should be positive. If they are not positive, set them to their defau