Project: Ellipsoid

Project: Ellipsoid List App Page 1 of 7
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Deliverables
Your project files should be submitted to Web-CAT by the due date and time specified. You may
submit your files to the skeleton code assignment until the project due date but should try to do this
much earlier. The skeleton code assignment is ungraded, but it checks that your classes and methods
are named correctly and that methods and parameters are correctly typed. The files you submit to
skeleton code assignment may be incomplete in the sense that method bodies have at least a return
statement if applicable or they may be essentially completed files. In order to avoid a late penalty for
the project, you must submit your completed code files to Web-CAT no later than 11:59 PM on the
due date for the completed code. If you are unable to submit via Web-CAT, you should e-mail your
files in a zip file to your TA before the deadline.
Files to submit to Web-CAT (all three files must be submitted together):
• Ellipsoid.java
• EllipsoidList.java
• EllipsoidListApp.java
Specifications
Overview: You will write a program this week that is composed of three classes: the first class
defines Ellipsoid objects, the second class defines EllipsoidList objects, and the third,
EllipsoidListApp, reads in a file name entered by the user then reads the list name and Ellipsoid data
from the file, creates Ellipsoid objects and stores them in an ArrayList of Ellipsoid objects, creates an
EllipsoidList object with the list name and ArrayList, prints the EllipsoidList object, and then prints
summary information about the EllipsoidList object.
An Ellipsoid is a 3-D object whose plane sections are ellipses defined by three axes (a, b, c) as depicted
below. The formulas are provided to assist you in computing return values for the respective methods in
the Ellipsoid class described in this project.
Formulas for volume (V) and surface area
(S) are shown below.
� =
4����
3
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• Ellipsoid.java (assuming that you successfully created this class in the previous project, just
copy the file to your new project folder and go on to EllipsoidList.java on page 4.
Otherwise, you will need to create Ellipsoid.java as part of this project.)
Requirements: Create an Ellipsoid class that stores the label and three axes a, b, and c. The
values of the axes must be greater than zero. The Ellipsoid class also includes methods to set and
get each of these fields, as well as methods to calculate the volume and surface area of the
Ellipsoid object, and a method to provide a String value of an Ellipsoid object (i.e., a class
instance).
Design: The Ellipsoid class has fields, a constructor, and methods as outlined below.
(1) Fields (instance variables): label of type String, and axes a, b, and c of type double. Initialize
the String variable to "" and the double variables to 0 in their respective declarations. These
instance variables should be private so that they are not directly accessible from outside of the
Ellipsoid class, and these should be the only instance variables (i.e., fields) in the class.
(2) Constructor: Your Ellipsoid class must contain a public constructor that accepts four
parameters (see types of above) representing the label, a, b, and c. Instead of assigning the
parameters directly to the fields, the respective set method for each field (described below)
should be called. For example, instead of the statement label = labelIn; use the
statement setLabel(labelIn); Below are examples of how the constructor could be
used to create Ellipsoid objects. Note that although String and numeric literals are used for
the actual parameters (or arguments) in these examples, variables of the required type could
have been used instead of the literals.
Ellipsoid ex1 = new Ellipsoid ("Ex 1", 1, 2, 3);
Ellipsoid ex2 = new Ellipsoid (" Ex 2 ", 2.3, 5.5, 7.4);
Ellipsoid ex3 = new Ellipsoid ("Ex 3", 123.4, 234.5, 345.6);
(3) Methods: Usually a class provides methods to access and modify each of its instance
variables (known as get and set methods) along with any other required methods. The
methods for Ellipsoid, which should each be public, are described below. See formulas in
Code and Test below.
o getLabel: Accepts no parameters and returns a String representing the label field.
o setLabel: Takes a String parameter and returns a boolean. If the string parameter is
not null, then the label field is set to the “trimmed” String and the method returns true.
Otherwise, the method returns false and the label field is not set.
o getA: Accepts no parameters and returns a double representing field a.
o setA: Accepts a double parameter and returns a boolean as follows. If the double is
greater than zero, sets field a to the double passed in and returns true. Otherwise, the
method returns false and does not set the field. 
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o getB: Accepts no parameters and returns a double representing field b.
o setB: Accepts a double parameter and returns a boolean as follows. If the double is
greater than zero, sets field b to the double passed in and returns true. Otherwise, the
method returns false and does not set the field.
o getC: Accepts no parameters and returns a double representing field c.
o setC: Accepts a double parameter and returns a boolean as follows. If the double is
greater than zero, sets field c to the double passed in and returns true. Otherwise, the
method returns false and does not set the field.
o volume: Accepts no parameters and returns the double value for the volume calculated
using formula above and the values of axes fields a, b, c.
o surfaceArea: Accepts no parameters and returns the double value for the surface
area calculated using formula above and the values of axes fields a, b, c.
o toString: Returns a String containing the information about the Ellipsoid object
formatted as shown below, including decimal formatting ("#,##0.0###") for the
double values. Newline and tab escape sequences should be used to achieve the proper
layout. In addition to the field values (or corresponding “get” methods), the following
methods should be used to compute appropriate values in the toString method:
volume()and surfaceArea(). Each line should have no trailing spaces (e.g., there
should be no spaces before a newline (\n) character). The toString value for ex1, ex2,
and ex3 respectively are shown below (the blank lines are not part of the toString
values).
Ellipsoid "Ex 1" with axes a = 1.0, b = 2.0, c = 3.0 units has:
 volume = 25.1327 cubic units
 surface area = 48.9366 square units
Ellipsoid "Ex 2" with axes a = 2.3, b = 5.5, c = 7.4 units has:
 volume = 392.1127 cubic units
 surface area = 317.9245 square units
Ellipsoid "Ex 3" with axes a = 123.4, b = 234.5, c = 345.6 units has:
 volume = 41,890,963.5508 cubic units
 surface area = 674,164.7034 square units
Code and Test: As you implement your Ellipsoid class, you should compile it and then test it
using interactions. For example, as soon you have implemented and successfully compiled the
constructor, you should create instances of Ellipsoid in interactions (e.g., copy/paste the examples
above on page 2). Remember that when you have an instance on the workbench, you can unfold
it to see its values. You can also open a viewer canvas window and drag the instance from the
Workbench tab to the canvas window. After you have implemented and compiled one or more
methods, create an Ellipsoid object in interactions and invoke each of your methods on the object
to make sure the methods are working as intended. You may find it useful to create a separate
class with a main method that creates an instance of Ellipsoid then prints it out. This would be
similar to the EllipsoidApp class from the previous project, except that in the EllipsoidApp class
you will read in the values and then create and print the object.
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• EllipsoidList.java
Requirements: Create an EllipsoidList class that stores the name of the list and an ArrayList of
Ellipsoid objects. It also includes methods that return the name of the list, number of Ellipsoid
objects in the EllipsoidList, total volume, total surface area, average volume, and average surface
for all Ellipsoid objects in the EllipsoidList. The toString method returns a String containing the
name of the list followed by each Ellipsoid in the ArrayList, and a summaryInfo method returns
summary information about the list (see below).
Design: The EllipsoidList class has two fields, a constructor, and methods as outlined below.
(1) Fields (or instance variables): (1) a String representing the name of the list and (2) an
ArrayList of Ellipsoid objects. These are the only fields (or instance variables) that this class
should have, and both should be private.
(2) Constructor: Your EllipsoidList class must contain a constructor that accepts a parameter of
type String representing the name of the list and a parameter of type ArrayList<Ellipsoid>
representing the list of Ellipsoid objects. These parameters should be used to assign the fields
described above (i.e., the instance variables).
(3) Methods: The methods for EllipsoidList are described below.
o getName: Returns a String representing the name of the list.
o numberOfEllipsoids: Returns an int representing the number of Ellipsoid objects
in the EllipsoidList. If there are zero Ellipsoid objects in the list, zero should be returned.
o totalVolume: Returns a double representing the total volume for all Ellipsoid objects
in the list. If there are zero Ellipsoid objects in the list, zero should be returned.
o totalSurfaceArea: Returns a double representing the total surface area for all
Ellipsoid objects in the list. If there are zero Ellipsoid objects in the list, zero should be
returned.
o averageVolume: Returns a double representing the average volume for all Ellipsoid
objects in the list. If there are zero Ellipsoid objects in the list, zero should be returned.
o averageSurfaceArea: Returns a double representing the average surface area for
all Ellipsoid objects in the list. If there are zero Ellipsoid objects in the list, zero should
be returned.
o toString: Returns a String (does not begin with \n) containing the name of the list
followed by each Ellipsoid in the ArrayList. In the process of creating the return result,
this toString() method should include a while loop that calls the toString() method for
each Ellipsoid object in the list (adding a \n before and after each). Be sure to include
appropriate newline escape sequences. For an example, see lines 3 through 16 in the
output below from EllipsoidListApp for the Ellipsoid_data_1.txt input file. [Note that the
toString result should not include the summary items in lines 18 through 24 of the
example. These lines represent the return value of the summaryInfo method below.]
o summaryInfo: Returns a String (does not begin with \n) containing the name of the
list (which can change depending of the value read from the file) followed by various
summary items: number of Ellipsoid objects, total volume, total surface area, average
volume, and average surface area. Use "#,##0.0###" as the pattern to format the double 
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values. For an example, see lines 18 through 24 in the output below from
EllipsoidListApp for the Ellipsoid_data_1.txt input file. The second example below
shows the output from EllipsoidListApp for the Ellipsoid_data_0.txt input file which
contains a list name but no Ellipsoid data.
Code and Test: Remember to import java.util.ArrayList. Each of the last five methods above
requires that you use a loop (i.e., a while loop) to retrieve each object in the ArrayList. As you
implement your EllipsoidList class, you can compile it and then test it using interactions.
However, it may be easier to create a class with a simple main method that creates an
EllipsoidList object and calls its methods.
• EllipsoidListApp.java
Requirements: Create an EllipsoidListApp class with a main method that (1) reads in the name
of the data file entered by the user and (2) reads list name and Ellipsoid data from the file, (3)
creates Ellipsoid objects, storing them in a local ArrayList of Ellipsoid objects; and finally, (4)
creates an EllipsoidList object with the name of the list and the ArrayList of Ellipsoid objects,
and then prints the EllipsoidList object followed summary information about the EllipsoidList
object. All input and output for this project must be done in the main method.
• Design: The main method should prompt the user to enter a file name, and then it should read in
the data file. The first record (or line) in the file contains the name of the list. This is followed by
the data for the Ellipsoid objects. Within a while loop, each set of Ellipsoid data (i.e., label, and
axes a, b, and c) is read in, and an Ellipsoid object should be created and added to the local
ArrayList of Ellipsoid objects. After the file has been read in and the ArrayList has been
populated, the main method should create an EllipsoidList object with the name of the list and the
ArrayList of Ellipsoid objects as parameters in the constructor. It should then print the
EllipsoidList object, and then print the summary information about the EllipsoidList (i.e., print
the value returned by the summaryInfo method for the EllipsoidList). The output from two runs
of the main method in EllipsoidListApp is shown below. The first is produced after reading in
the Ellipsoid_data_1.txt file, and the second is produced after reading in the Ellipsoid_data_0.txt
file. Your program output should be formatted exactly as shown on the next page.
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Program output
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----jGRASP exec: java EllipsoidListApp
Enter file name: Ellipsoid_data_1.txt
Ellipsoid Test List
Ellipsoid "Ex 1" with axes a = 1.0, b = 2.0, c = 3.0 units has:
 volume = 25.1327 cubic units
 surface area = 48.9366 square units
Ellipsoid "Ex 2" with axes a = 2.3, b = 5.5, c = 7.4 units has:
 volume = 392.1127 cubic units
 surface area = 317.9245 square units
Ellipsoid "Ex 3" with axes a = 123.4, b = 234.5, c = 345.6 units has:
 volume = 41,890,963.5508 cubic units
 surface area = 674,164.7034 square units
----- Summary for Ellipsoid Test List -----
Number of Ellipsoid Objects: 3
Total Volume: 41,891,380.796 cubic units
Total Surface Area: 674,531.564 square units
Average Volume: 13,963,793.599 cubic units
Average Surface Area: 224,843.855 square units
----jGRASP: operation complete.
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----jGRASP exec: java EllipsoidListApp
Enter file name: Ellipsoid_data_0.txt
Ellipsoid Empty Test List
----- Summary for Ellipsoid Empty Test List -----
Number of Ellipsoid Objects: 0
Total Volume: 0.0 cubic units
Total Surface Area: 0.0 square units
Average Volume: 0.0 cubic units
Average Surface Area: 0.0 square units
----jGRASP: operation complete.
Code: Remember to import java.util.ArrayList, java.util.Scanner, and java.io.File, and
java.io.FileNotFoundException prior to the class declaration. Your main method declaration
should indicate that main throws FileNotFoundException. After your program reads in
the file name from the keyboard, it should read in the data file using a Scanner object that was
created on a file using the file name entered by the user.
 ... = new Scanner(new File(fileName));
You can assume that the first line in the data file is the name of the list, and then each set of four
lines contains the data from which an Ellipsoid object can be created. After the name of the list
has been read and assigned to a local variable, a while loop should be used to read in the Ellipsoid
data. The boolean expression for the while loop should be (_________.hasNext()) where 
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the blank is the name of the Scanner you created on the file. Each iteration through the loop reads
four lines. As each of the lines is read from the file, the respective local variables for the
Ellipsoid data items (label, a, b, and c) should be assigned, after which the Ellipsoid object should
be created and added to a local ArrayList of Ellipsoid objects. The next iteration of the loop
should then read the next set of four lines then create the next Ellipsoid object and add it to the
local ArrayList of Ellipsoid objects, and so on. After the file has been processed (i.e., when the
loop terminates after the hasNext method returns false), name of the list and the ArrayList of
Ellipsoid objects should be used to create an EllipsoidList object. The list should be printed by
printing a leading \n and the EllipsoidList object. Finally, the summary information is printed by
printing a leading \n and the value returned by the summaryInfo method invoked on the
EllipsoidList object.
Test: You should test your program minimally (1) by reading in the Ellipsoid_data_1.txt input
file, which should produce the first output above, and (2) by reading in the Ellipsoid_data_0.txt
input file, which should produce the second output above. Although your program may not use
all of the methods in the EllipsoidList and Ellipsoid classes, you should ensure that all of your
methods work according to the specification. You can either user interactions in jGRASP or you
can write another class and main method to exercise the methods. Web-CAT will test all
methods to determine your project grade.
General Notes
1. All input from the keyboard and all output to the screen should done in the main method.
Only one Scanner object on System.in should be created and this should be done in the main
method. All printing (i.e., using the System.out.print and/or System.out.println methods)
should be in the main method. Hence, none of your methods in the Ellipsoid class should do
any input/output (I/O).
2. Be sure to download the test data files (Ellipsoid_data_1.txt and Ellipsoid_data_0.txt) and
store them in same folder as your source files. It may be useful examine the contents of the
data files. Find the data files in the jGRASP Browse tab and then open each data file in
jGRASP to see the items that your program will be reading from the file. Be sure to close the
data files without changing them.