Description
Files to submit to Web-CAT (all three files must be submitted together):
• Trapezohedron.java
• TrapezohedronList.java
• TrapezohedronListApp.java
A pentagonal trapezohedron (or a pentagonal deltohedron) is a polyhedron composed of 10 kites as
faces (with side lengths a and b), 20 edges, and 12 vertices. The formulas are provided to assist you in
computing return values for the respective methods in the Trapezohedron class described in this project.
(Sources: https://en.wikipedia.org/wiki/Pentagonal_trapezohedron#10-sided_dice
https://rechneronline.de/pi/trapezohedron.php) To use calculator, see Test paragraph on page 5.
Formulas for edge length antiprism (z), long edge length (b),
surface area (A), and volume (V) are shown below where � is the
short edge length, which will be read in.
� = �⁄(( √5 − 1)/2)
� = ((√5 + 1)/2) ∗ �
� = 225
2.0
∗ (5 + √5) ∗ �!
� = 5.0
12
∗ 63 + √58 ∗ �”
Specifications
Overview: You will write a program this week that is composed of three classes: the first class
defines Trapezohedron objects, the second class defines TrapezohedronList objects, and the third,
TrapezohedronListApp, reads in a file name entered by the user then reads the list name and
Trapezohedron data from the file, creates Trapezohedron objects and stores them in an ArrayList of
b
a
�
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Trapezohedron objects, creates an TrapezohedronList object with the list name and ArrayList, prints
the TrapezohedronList object, and then prints summary information about the TrapezohedronList
object.
• Trapezohedron.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 TrapezohedronList.java
on page 4. Otherwise, you will need to create Trapezohedron.java as part of this project.)
Requirements: Create an Trapezohedron class that stores the label, color, and short edge length,
which must be non-negative. The Trapezohedron class also includes methods to set and get each
of these three fields, as well as methods to calculate the edge length antiprism, the long edge
length, surface area, and volume of the Trapezohedron object, and a method to provide a String
value of an Trapezohedron object (i.e., a class instance).
Design: The Trapezohedron class has fields, a constructor, and methods as outlined below.
(1) Fields (instance variables): label of type String, color of type String, and short edge of type
double. Initialize the Strings to “” and the double to zero in their respective declarations.
These instance variables should be private so that they are not directly accessible from
outside of the Trapezohedron class, and these should be the only instance variables in the
class.
(2) Constructor: Your Trapezohedron class must contain a public constructor that accepts three
parameters (see types of above) representing the label, color, and short edge. 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 Trapezohedron 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.
Trapezohedron ex1 = new Trapezohedron (“Ex 1”, “red”, 5.0);
Trapezohedron ex2 = new Trapezohedron (” Ex 2 “, “blue”, 10.4);
Trapezohedron ex3 = new Trapezohedron (“Ex 3”, “red, blue, tan”, 24.5);
(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 Trapezohedron, which should each be public, are described below. See formulas
above.
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 getColor: Accepts no parameters and returns a String representing the color field.
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o setColor: Takes a String parameter and returns a boolean. If the string parameter is
not null, then the “trimmed” String is set to the color field and the method returns true.
Otherwise, the method returns false and the label is not set.
o getShortEdge: Accepts no parameters and returns a double representing the short
edge field.
o setShortEdge: Accepts a double parameter and returns a boolean as follows. If the
short edge is greater than zero, sets the short edge field to the double passed in and
returns true. Otherwise, the method returns false and the short edge is not set.
o edgeLengthAntiprism: Accepts no parameters and returns the double value for the
edge length antiprism calculated using the value for short edge (a) in the formula above.
o longEdge: Accepts no parameters and returns the double value for the long edge
calculated using the formula above.
o surfaceArea: Accepts no parameters and returns the double value for the surface
area calculated using the formula above.
o volume: Accepts no parameters and returns the double value for the volume calculated
using the using the formula above.
o toString: Returns a String containing the information about the Trapezohedron object
formatted as shown below, including decimal formatting (“#,##0.0###”) for the
double values. The newline (\n) and tab (\t) escape sequences should be used to achieve
the proper layout for the indented lines (use \t rather than three spaces for the
indentation). In addition to the field values (or corresponding “get” methods), the
following methods should be used to compute appropriate values in the toString method:
edgeLengthAntiprism(), longEdge(), surfaceArea(), and volume(). 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).
Trapezohedron “Ex 1” is “red” with 20 edges and 12 vertices.
edge length antiprism = 8.0902 units
short edge = 5.0 units
long edge = 13.0902 units
surface area = 622.4746 square units
volume = 1,155.226 cubic units
Trapezohedron “Ex 2” is “blue” with 20 edges and 12 vertices.
edge length antiprism = 16.8276 units
short edge = 10.4 units
long edge = 27.2276 units
surface area = 2,693.074 square units
volume = 10,395.7774 cubic units
Trapezohedron “Ex 3” is “red, blue, tan” with 20 edges and 12 vertices.
edge length antiprism = 39.6418 units
short edge = 24.5 units
long edge = 64.1418 units
surface area = 14,945.6145 square units
volume = 135,911.1879 cubic units
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Code and Test: As you implement your Trapezohedron 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 Trapezohedron 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 Trapezohedron 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 Trapezohedron then
prints it out.
• TrapezohedronList.java
Requirements: Create an TrapezohedronList class that stores the name of the list and an
ArrayList of Trapezohedron objects. It also includes methods that return the name of the list,
number of Trapezohedron objects in the TrapezohedronList, total surface area, total volume,
average surface, and average volume for all Trapezohedron objects in the TrapezohedronList.
The toString method returns a String containing the name of the list followed by each
Trapezohedron in the ArrayList, and a summaryInfo method returns summary information about
the list (see below).
Design: The TrapezohedronList 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 Trapezohedron objects. These are the only fields (or instance variables) that this
class should have, and both should be private.
(2) Constructor: Your TrapezohedronList class must contain a constructor that accepts a
parameter of type String representing the name of the list and a parameter of type
ArrayList representing the list of Trapezohedron objects. These parameters
should be used to assign the fields described above (i.e., the instance variables).
(3) Methods: The methods for TrapezohedronList are described below.
o getName: Returns a String representing the name of the list.
o numberOfTrapezohedrons: Returns an int representing the number of
Trapezohedron objects in the TrapezohedronList. If there are zero Trapezohedron objects
in the list, zero should be returned.
o totalSurfaceArea: Returns a double representing the total surface area for all
Trapezohedron objects in the list. If there are zero Trapezohedron objects in the list, zero
should be returned.
o totalVolume: Returns a double representing the total volume for all Trapezohedron
objects in the list. If there are zero Trapezohedron objects in the list, zero should be
returned.
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o averageSurfaceArea: Returns a double representing the average surface area for
all Trapezohedron objects in the list. If there are zero Trapezohedron objects in the list,
zero should be returned.
o averageVolume: Returns a double representing the average volume for all
Trapezohedron objects in the list. If there are zero Trapezohedron 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 Trapezohedron 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 Trapezohedron 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 25 in
the output below from TrapezohedronListApp for the Trapezohedron_data_1.txt input
file. [Note that the toString result should not include the summary items in lines 27
through 33 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 on the value read from the file) followed by various
summary items: number of Trapezohedron objects, total surface area, total volume,
average surface area, and average volume. Use “#,##0.0##” as the pattern to format the
double values. For an example, see lines 27 through 33 in the output below from
TrapezohedronListApp for the Trapezohedron_data_1.txt input file. The second example
below shows the output from TrapezohedronListApp for the Trapezohedron_data_0.txt
input file which contains a list name but no Trapezohedron data.
Code and Test: Remember to import java.util.ArrayList. Each of the four methods above that
finds a total or average requires that you use a loop (i.e., a while loop) to retrieve each object in
the ArrayList. As you implement your TrapezohedronList 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 TrapezohedronList object and calls its methods.
• TrapezohedronListApp.java
Requirements: Create an TrapezohedronListApp 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 Trapezohedron data from the
file, (3) creates Trapezohedron objects, storing them in a local ArrayList of Trapezohedron
objects; and finally, (4) creates an TrapezohedronList object with the name of the list and the
ArrayList of Trapezohedron objects, and then prints the TrapezohedronList object followed
summary information about the TrapezohedronList 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 Trapezohedron objects. Within a while loop, each set of Trapezohedron data (i.e.,
label, color, and short edge) is read in, and then an Trapezohedron object should be created and
added to the local ArrayList of Trapezohedron objects. After the file has been read in and the
ArrayList has been populated, the main method should create an TrapezohedronList object with
the name of the list and the ArrayList of Trapezohedron objects as parameters in the constructor.
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It should then print the TrapezohedronList object, and then print the summary information about
the TrapezohedronList (i.e., print the value returned by the summaryInfo method for the
TrapezohedronList). The output from two runs of the main method in TrapezohedronListApp is
shown below. The first is produced after reading in the Trapezohedron_data_1.txt file, and the
second is produced after reading in the Trapezohedron_data_0.txt file. Your program output
should be formatted exactly as shown on the next page.
Example 1
Line
#
Program output
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
—-jGRASP exec: java TrapezohedronListApp
Enter file name: Trapezohedron_data_1.txt
Trapezohedron Test List
Trapezohedron “Ex 1” is “red” with 20 edges and 12 vertices.
edge length antiprism = 8.0902 units
short edge = 5.0 units
long edge = 13.0902 units
surface area = 622.4746 square units
volume = 1,155.226 cubic units
Trapezohedron “Ex 2” is “blue” with 20 edges and 12 vertices.
edge length antiprism = 16.8276 units
short edge = 10.4 units
long edge = 27.2276 units
surface area = 2,693.074 square units
volume = 10,395.7774 cubic units
Trapezohedron “Ex 3” is “red, blue, tan” with 20 edges and 12 vertices.
edge length antiprism = 39.6418 units
short edge = 24.5 units
long edge = 64.1418 units
surface area = 14,945.6145 square units
volume = 135,911.1879 cubic units
—– Summary for Trapezohedron Test List —–
Number of Trapezohedrons: 3
Total Surface Area: 18,261.163 square units
Total Volume: 147,462.191 cubic units
Average Surface Area: 6,087.054 square units
Average Volume: 49,154.064 cubic units
—-jGRASP: operation complete.
Example 2
Line # Program output
1
2
3
4
5
6
7
8
—-jGRASP exec: java TrapezohedronListApp
Enter file name: Trapezohedron_data_0.txt
Trapezohedron Empty Test List
—– Summary for Trapezohedron Empty Test List —–
Number of Trapezohedrons: 0
Total Surface Area: 0.0 square units
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9
10
11
12
Total Volume: 0.0 cubic units
Average Surface Area: 0.0 square units
Average Volume: 0.0 cubic 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 three
lines contains the data from which an Trapezohedron 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
Trapezohedron data. The boolean expression for the while loop should be
(_________.hasNext()) where the blank is the name of the Scanner you created on the file.
Each iteration through the loop reads three lines. As each of the lines is read from the file, the
respective local variables for the Trapezohedron data items (label, color, edge) should be
assigned, after which the Trapezohedron object should be created and added to a local ArrayList
of Trapezohedron objects. The next iteration of the loop should then read the next set of three
lines then create the next Trapezohedron object and add it to the local ArrayList of
Trapezohedron 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
Trapezohedron objects should be used to create an TrapezohedronList object. Then the list
should be printed by printing a leading \n and the TrapezohedronList object. Finally, the
summary information is printed by printing a leading \n and the value returned by the
summaryInfo method invoked on the TrapezohedronList object.
Test: You should test your program minimally (1) by reading in the Trapezohedron_data_1.txt
input file, which should produce the first output above, and (2) by reading in the
Trapezohedron_data_0.txt input file, which should produce the second output above. Although
your program may not use all the methods in the TrapezohedronList and Trapezohedron 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 Trapezohedron class
should do any input/output (I/O).
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2. Be sure to download the test data files (Trapezohedron_data_1.txt and
Trapezohedron_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.
