Description
Specifications
Overview: You will write a program this week that is composed of three classes: the first class
defines Cone objects, the second class defines ConeList objects, and the third, ConeListApp, reads in
a file name entered by the user then reads the list name and Cone data from the file, creates Cone
objects and stores them in an ArrayList of Cone objects, creates an ConeList object with the list name
and ArrayList, prints the ConeList object, and then prints summary information about the ConeList
object.
A cone is a 3-D geometric shape that tapers smoothly from a flat base to a point
called the apex or vertex. A cone can be defined by its height and radius (h, r) as
depicted below.
The formulas are provided to assist you in computing return values
for the respective methods in the Cone class described in this project. [Wikipedia]
Nomenclature
height: h
radius of base: r
perimeter of base: P
base area: B
slant height: s
side area: S
total surface area: T
Volume: V
Formulas
P = 2��
B = ��!
s = ‘r! + h!
S = �rs
T = �r(r + s)
V = ��!h/3
• Cone.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 ConeList.java on page 4. Otherwise,
you will need to create Cone.java as part of this project.)
Requirements: Create a Cone class that stores the label, height, and radius (height and radius
each must be greater than zero). The Cone class also includes methods to set and get each of
these fields, as well as methods to calculate the base perimeter, base area, slant height, side area,
surface area, and volume of a Cone object, and a method to provide a String value of a Cone
object (i.e., an instance of the Cone class).
Design: The Cone class has fields, a constructor, and methods as outlined below.
(1) Fields (instance variables): label of type String, height of type double, and radius of type
double. These instance variables should be private so that they are not directly accessible
from outside of the Cone class, and these should be the only instance variables in the class.
(2) Constructor: Your Cone class must contain a constructor that accepts three parameters (see
types of above) representing the label, height, and radius. 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 Cone 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.
Cone example1 = new Cone(“Short Example”, 3.0, 4.0);
Cone example2 = new Cone(” Wide Example “, 10.6, 22.1);
Cone example3 = new Cone(“Tall Example”, 100, 20);
(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 Cone are described below. See the formulas above and “Code and Test” below
for details. When implementing the formulas, be sure to use the Math constant Math.PI for �
and the methods Math.pow and Math.sqrt as appropriate.
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 “trimmed” String is set to the label field and the method returns true.
Otherwise, the method returns false and the label is not set.
o getHeight: Accepts no parameters and returns a double representing the height field.
o setHeight: Accepts a double parameter and returns a boolean. If the height is greater
than zero, sets height field and returns true. Otherwise, the method returns false and the
height is not set.
o getRadius: Accepts no parameters and returns a double representing the radius field.
o setRadius: Accepts a double parameter and returns a boolean. If the radius is greater
than zero, sets radius field and returns true. Otherwise, the method returns false and the
radius is not set.
o basePerimeter: Accepts no parameters and returns the double value for the
perimeter of the base circle of the cone calculated using radius.
o baseArea: Accepts no parameters and returns the double value for the base area
calculated using radius.
o slantHeight: Accepts no parameters and returns the double value for the slant height
calculated using height and radius.
o sideArea: Accepts no parameters and returns the double value for the side area
calculated using radius and slant height.
o surfaceArea: Accepts no parameters and returns the double value for the total
surface area calculated using the base area and side area.
o volume: Accepts no parameters and returns the double value for the volume calculated
using height and radius.
o toString: Returns a String containing the information about the Cone object
formatted as shown below, including decimal formatting (“#,##0.0##”) for the double
values.
Newline 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: basePerimeter(),
baseArea(), slantHeight(), sideArea(), surfaceArea(), and volume(). Each line should
have no leading and no trailing spaces (e.g., there should be no spaces before a newline
(\n) character). The toString value for example1, example2, and example3 respectively
are shown below (the blank lines are not part of the toString values).
“Short Example” is a cone with height = 3.0 units and radius = 4.0 units,
which has base perimeter = 25.133 units, base area = 50.265 square units,
slant height = 5.0 units, side area = 62.832 square units,
surface area = 113.097 square units, and volume = 50.265 cubic units.
“Wide Example” is a cone with height = 10.6 units and radius = 22.1 units,
which has base perimeter = 138.858 units, base area = 1,534.385 square units,
slant height = 24.511 units, side area = 1,701.752 square units,
surface area = 3,236.137 square units, and volume = 5,421.495 cubic units.
“Tall Example” is a cone with height = 100.0 units and radius = 20.0 units,
which has base perimeter = 125.664 units, base area = 1,256.637 square units,
slant height = 101.98 units, side area = 6,407.617 square units,
surface area = 7,664.254 square units, and volume = 41,887.902 cubic units.
Code and Test: As you implement your Cone 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 Cone in interactions (see the examples above).
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 a Cone
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 Cone then prints is out. This would be similar to the class you will
create in ConeApp, except that in ConeApp you will read in the values and then create the object.
• ConeList.java
Requirements: Create a ConeList class that stores the name of the list and an ArrayList of Cone
objects. It also includes methods that return the name of the list, number of Cone objects in the
ConeList, total surface area, total volume, total base perimeter, total base area, average surface
area, and average volume for all Cone objects in the ConeList. The toString method returns a
String containing the name of the list followed by each Cone in the ArrayList, and a summaryInfo
method returns summary information about the list (see below).
Design: The ConeList 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 Cone objects. These instance variables should be private so that they are not
directly accessible from outside of the ConeList class, and these should be the only instance
variables in the class.
(2) Constructor: Your ConeList class must contain a constructor that accepts a parameter of
type String representing the name of the list and a parameter of type ArrayList< Cone>
representing the list of Cone objects. These parameters should be used to assign the fields
described above (i.e., the instance variables).
(3) Methods: The methods for ConeList are described below.
o getName: Returns a String representing the name of the list.
o numberOfCones: Returns an int representing the number of Cone objects in the
ConeList. If there are zero Cone objects in the list, zero should be returned.
o totalBasePerimeter: Returns a double representing the total for the base
perimeters for all Cone objects in the list. If there are zero Cone objects in the list, zero
should be returned.
o totalBaseArea: Returns a double representing the total for the base areas for all
Cone objects in the list. If there are zero Cone objects in the list, zero should be returned.
o totalSlantHeight: Returns a double representing the total for the slant heights for
all Cone objects in the list. If there are zero Cone objects in the list, zero should be
returned.
o totalSideArea: Returns a double representing the total for the side areas for all
Cone objects in the list. If there are zero Cone objects in the list, zero should be returned.
o totalSurfaceArea: Returns a double representing the total surface areas for all
Cone objects in the list. If there are zero Cone objects in the list, zero should be returned.
o totalVolume: Returns a double representing the total volumes for all Cone objects in
the list. If there are zero Cone objects in the list, zero should be returned.
o averageSurfaceArea: Returns a double representing the average surface area for
all Cone objects in the list. If there are zero Cone objects in the list, zero should be
returned.
o averageVolume: Returns a double representing the average volume for all Cone
objects in the list. If there are zero Cone 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 Cone 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
Cone object in the list. Be sure to include appropriate newline escape sequences.
For an
example, see lines 3 through 24 in the output below from ConeListApp for the cone_1.txt
input file. [Note that the toString result should not include the summary items in lines 26
through 35. 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 cones, total base perimeter, total base area, total slant heights,
total side areas, total surface area, total volume, average surface area, average volume.
For an example, see lines 26 through 35 in the output below from ConeListApp for the
cone_1.txt input file. The second example below shows the output from ConeListApp for
the cone_0.txt input file which contains a list name but no cone data.
Code and Test: Remember to import java.util.ArrayList. Each of the methods above requires
that you use a loop (i.e., a while loop) to retrieve each object in the ArrayList. As you implement
your ConeList class, you can compile it and then test it using interactions. Alternatively, you can
create a class with a simple main method that creates a ConeList object and calls its methods.
• ConeListApp.java
Requirements: Create a ConeListApp class with a main method that (1) reads in the name of the
input file entered by the user and then (2) reads list name and Cone data from the file, (3) creates
Cone objects, stores them in a local ArrayList of Cone objects, and finally (4) creates an ConeList
object with the name of the list and the ArrayList of Cone objects, and then prints the ConeList
object followed summary information about the ConeList object. All input and output for this
project should 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 file. The first record (or line) in the file contains the name of the list. This is followed by the
data for the Cone objects. After each set of Cone data is read in, a Cone object should be created
and stored in the local ArrayList.
After the file has been read in and the ArrayList created, the
main method should create a ConeList object with the name of the list and the ArrayList of Cone
objects as parameters in the constructor. It should then print the ConeList object followed by
summary information about the ConeList (i.e., print the value returned by the summaryInfo
method for the ConeList).
The output from two runs of the main method in ConeListApp is
shown below: the first produced after reading in the cone_1.txt file and the second after reading in
the cone_0.txt file. Your program output should be formatted exactly as follows).
Line # Program output
1
2
3
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5
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10
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14
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—-jGRASP exec: java ConeListApp
Enter file name: cone_1.txt
Cone List 1
“Short Example” is a cone with height = 3.0 units and radius = 4.0 units,
which has base perimeter = 25.133 units, base area = 50.265 square units,
slant height = 5.0 units, side area = 62.832 square units,
surface area = 113.097 square units, and volume = 50.265 cubic units.
“Wide Example” is a cone with height = 10.6 units and radius = 22.1 units,
which has base perimeter = 138.858 units, base area = 1,534.385 square units,
slant height = 24.511 units, side area = 1,701.752 square units,
surface area = 3,236.137 square units, and volume = 5,421.495 cubic units.
“Tall Example” is a cone with height = 100.0 units and radius = 20.0 units,
which has base perimeter = 125.664 units, base area = 1,256.637 square units,
slant height = 101.98 units, side area = 6,407.617 square units,
surface area = 7,664.254 square units, and volume = 41,887.902 cubic units.
“Really Large Example” is a cone with height = 300.0 units and radius = 400.0 units,
which has base perimeter = 2,513.274 units, base area = 502,654.825 square units,
slant height = 500.0 units, side area = 628,318.531 square units,
surface area = 1,130,973.355 square units, and volume = 50,265,482.457 cubic units.
—– Summary for Cone List 1 —–
Number of Cones: 4
Total Base Perimeter: 2,802.929
Total Base Area: 505,496.112
Total Slant Height: 631.491
Total Side Area: 636,490.731
Total Surface Area: 1,141,986.844
Total Volume: 50,312,842.12
Average Surface Area: 285,496.711
Average Volume: 12,578,210.53
—-jGRASP: operation complete.
Line # Program output
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
—-jGRASP exec: java ConeListApp
Enter file name: cone_0.txt
Empty List of Cones
—– Summary for Empty List of Cones —–
Number of Cones: 0
Total Base Perimeter: 0.0
Total Base Area: 0.0
Total Slant Height: 0.0
Total Side Area: 0.0
Total Surface Area: 0.0
Total Volume: 0.0
Average Surface Area: 0.0
Average Volume: 0.0
—-jGRASP: operation complete.
Code: Remember to import java.util.ArrayList, java.util.Scanner, and java.io.File, and
java.io.IOException prior to the class declaration. Your main method declaration should indicate
that main throws IOException. After your program reads in the file name from the
keyboard, it should read in the 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 file is the name of the list, and then each set of three lines
contains the data from which a Cone 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 cone 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 cone data items
(label, side, and height) should be assigned, after which the Cone object should be created and
added to a local ArrayList. The next iteration of the loop should then read the next set of three
lines then create the next Cone object and add it to a local ArrayList, 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 should be used to create a ConeList object. The ConeList object should
then be printed. Finally, the summary information is printed by printing the value returned by the
summaryInfo method invoked on the ConeList object.
Test: You should test your program minimally (1) by reading in the cone_1.txt input file, which
should produce the first output above, and (2) by reading in the cone_0.txt input file, which
should produce the second output above. Although your program may not use all of the methods
in ConeList and Cone, 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 System.out.println methods) should
be in the main method. Hence, none of your methods in the Cone class should do any
input/output (I/O).
2. Be sure to download the test data files (cone_1.txt and cone_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.
