ASSIGNMENT 5 COMP-202

ASSIGNMENT 5
COMP-202
Please read the entire PDF before starting. You must do this assignment individually.
Question 1: 100 points
100 points total
It is very important that you follow the directions as closely as possible. The directions, while
perhaps tedious, are designed to make it as easy as possible for the TAs to mark the assignments by letting
them run your assignment, in some cases through automated tests. While these tests will never be used to
determine your entire grade, they speed up the process significantly, which allows the TAs to provide better
feedback and not waste time on administrative details. Plus, if the TA is in a good mood while he or she is
grading, then that increases the chance of them giving out partial marks. :)
Up to 30% can be removed for bad indentation of your code as well as omitting comments, or poor coding
structure.
To get full marks, you must:
• Follow all directions below
– In particular, make sure that all classes and method names are spelled and capitalized exactly
as described in this document. Otherwise, you will receive a 50% penalty.
• Make sure that your code compiles
– Non-compiling code will receive a 0.
• Write your name and student ID as a comment in all .java files you hand in
• Indent your code properly
• Name your variables appropriately
– The purpose of each variable should be obvious from the name
• Comment your work
– A comment every line is not needed, but there should be enough comments to fully understand
your program
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Part 1 (0 points): Warm-up
Do NOT submit this part, as it will not be graded. However, doing these exercises might help you to do the
second part of the assignment, which will be graded. If you have difficulties with the questions of Part 1, then
we suggest that you consult the TAs during their office hours; they can help you and work with you through
the warm-up questions. You are responsible for knowing all of the material in these questions.
Warm-up Question 1 (0 points)
Write a program that opens a .txt, reads the contents of the file line by line, and prints the content
of each line. To do this, you should look up how to use the BufferedReader or FileReader class1
.
Remember to use the try and catch blocks to handle errors like trying to open an non-existent file. A
sample file for testing file reading is found in the provided files as dictionary.txt.
Warm-up Question 2 (0 points)
Modify the previous program so that it stores every line in an ArrayList of String objects. You have
to properly declare an ArrayList to store the results, and use add to store every line that your program
reads in the ArrayList.
Warm-up Question 3 (0 points)
Modify your program so that, after reading all the content in the file, it prints how many words are
inside the text file. To do this, you should use the split method of the String class. Assume the only
character that separates words is whitespace " ".
Warm-up Question 4 (0 points)
Create a new method in your program which takes your ArrayList of Strings, and writes it to a file.
Use the FileWriter and BufferedWriter classes in order to access the file and write the Strings. In
the output file, there should be one String per line, just like the original file you loaded the ArrayList
from.
Warm-up Question 5 (0 points)
Create a new method in your program which takes as input your ArrayList of Strings, and sort all the
elements. The sorting criterion will be the length of the string. In other words, after calling this method,
the shortest string must be located in the first position, the second shortest in the second position an so
on.
Warm-up Question 6 (0 points)
Create a new method in your program which takes as input a sorted ArrayList (see the previous
question for details about the sorting criterion) and two ints. The two ints will represent a range of
values. This method should return an ArrayList with all the Strings whose length is inside that range.
For example, if your original ArrayList is equal to {"aa","aaa","aaaa","aaaaa"} and the two
ints are 3 and 4, your method must return the ArrayList {"aaa","aaaa"} (because the length of the
returned Strings is within 3 and 4).
1The documentation ofn the BufferedReader class is available at http://docs.oracle.com/javase/8/docs/api/java/
io/BufferedReader.html. You can find an example on how to use it at http://www.tutorialspoint.com/java/io/
bufferedreader_readline.htm
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Part 2
The questions in this part of the assignment will be graded.
Question 1: Tamagotchi (100 points)
For this question, you will write a number of classes that you can use to implement a game that simulates
a Tamagotchi. Your code for this assignment will go in multiple .java files. Note that in addition to
the required methods below, you are free to add as many other private methods as you see fit. It is
up to you to figure out if the methods from the Toy class and the Tamagotchi class should be static or
not. Playground and FileIO are utilities classes, therefore all their methods should be static.
We strongly recommend that you complete the first four warm-up questions before starting
this problem.
The general idea of the assignment is to implement a new data type Tamagotchi. An object of type
Tamagotchi should be able to perform some basic tasks such as play, eat, and sleep. As a consequence to
these actions the Tamagotchi’s energy and experience will change. In addition to this, you will implement
two utility classes that will allow you to use a Tamagotchi and to save the progress done each time you
close the program.
(a) (25 points) Toy Class
Toy.java represents a toy that a Tamagotchi will be able to play with. You are provided with some
starter code for this class. Note that this code already contains four private static attributes as
well as three private static methods. You should use them when you implement the rest of the
class.
The Toy class should contain the following private attributes:
• A String name
• A String color
• A String type
• A int representing the experience gained by playing with this Toy.
The class also contains the following public methods.
• Two constructors:
– One constructor that takes as input three Strings, and an int. These parameters represent
the name, color, type, and experience awarded by the Toy, in that order. The constructor
should use its inputs to initialize the attributes accordingly.
– A second constructor that takes no inputs and initializes the attributes with values generated at random. Use getRandomName(), getRandomColor(), and getRandomType() to
initialize the corresponding attributes. Generate a random integer between 10 (included)
and 25 (excluded) to initialize the attribute representing the experience awarded by the toy.
• A getName(), getColor(), getType(), and getXp() to retrieve the corresponding attributes’
values.
• The toString() method
This method returns a String consisting of the toy’s name, color, and type. For example, the
method might return the following: "Trooper the yellow stuffed cat", where “Trooper” is
the name of the toy, “yellow” is its color, and “stuffed cat” is its type. This method will be very
handy for debugging your code, and you can use it whenever you need to display information
about a toy.
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• createToy() method
This method takes a String as input containing all the information needed to represent a Toy.
The method returns a Toy created using such information. A valid input String will contain
the name, the color, the type, and the experience to be awarded. Each piece of information
will be separated by a tab character (\t). You can use the method split() from the String
class to help you isolate each piece. If the input does not contain 4 pieces of information your
method should throw an IllegalArgumentException. Otherwise the method will proceed to
create the corresponding Toy and return it.
• findBestToy() method
This method takes an ArrayList of Toys as input and returns the Toy that awards the greatest
experience for playing with it. If the list is empty the method should return null. If there’s
more than one Toy awarding the highest experience, then the first one in the list should be
returned.
(b) (50 points) Tamagotchi Class
Note that you are provided with some starter code for this class too. The code already contains
two private static attributes.
The Tamagotchi class should contain the following private attributes:
• A String representing its name
• An int indicating its level
• A double indicating its energy
• An int representing its experience points
• An int indicating how many meals the tamagotchi has consumed.
• An ArrayList of toys containing all its toys.
The class also contains the following public methods.
• Two constructors:
– One constructor that takes as input a String, an int, a double, two ints, and an
ArrayList of Toys. These parameters represent the name, level, energy, experience, meals
consumed, and toys of a tamagotchi, in that order. The constructor should use its inputs
to initialize the attributes accordingly. Remember how you should initialize attributes that
are mutable reference types.
– A second constructor that takes as input only one String representing the name of the
tamagotchi. The constructor uses the input to initialize the attribute name, and then it
initializes the remaining attributes as follow:
∗ level with 1
∗ energy with MAX ENERGY (10.0)
∗ experience with 0
∗ meals consumed with 0
∗ the list of toys with a list with one element containing a Toy generated at random.
• A getName(), getLevel(), getEnergy(), getXp(), getNumOfMeals(), and getToys() to retrieve the corresponding attributes’ values. Remember how you should write a get method
when dealing with attributes that are mutable reference types.
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• A private method called levelUp()
This method does not receive any input. It checks whether the tamagotchi has enough experience to level up. If its experience is greater than or equal to 50 ∗ level ∗ (level + 1)/2, then
the tamagotchi should level up. This is obtained by increasing its level by one, resetting the
meals consumed to 0, and creating a brand new toy (randomly generated) to be added to its
list of toys. The method should also print a message letting the user know that the tamagotchi
has levelled up, its new level, and which new toy was added to the list. If the experience of the
tamagotchi is not enough to level up, then the method does not do anything. An example of
the method output could be the following:
*** YAY, time to level up!! ***
Mimitchi is now level 2
Your new toy is Mary the blue ball
• The play() method
This method takes as input an integer indicating a playing mode. You can assume that this
integer is going to be either equal to 1 or to 2. The method should do the following:
– If the Tamagotchi has no toys or it has energy less than 2, then the method throws an
IllegalStateException with a message indicating that the tamagotchi is not able to
play.
– Otherwise, if the playing mode is 1, the method selects the best toy out of this tamagotchi’s
toys, if the playing mode is equal to 2, it selects a random toy.
– The method updates the experience and the energy of the tamagotchi. Let the experience
gained be equal to x, then the energy used by the tamagotchi to play is a random double
between x/20.0 (included) and x/20.0 + 0.5 (excluded).
– The method displays messages indicating which toy the tamagotchi played with and what
are its energy and experience as a consequence of this.
– Finally, the method should call levelUp() in case the experience gained was enough for
the tamagotchi to change level.
For example, when called, the method might display the following:
Mimitchi played with Trooper the yellow stuffed cat and earned 17 xp.
Mimitchi has now 135 xp, and 8.78 energy.
• The feed() method
This method takes no inputs. If the energy of the tamagotchi is less than 1 or if the tamagotchi
has already consumed a number of meals greater than or equal to twice its current level, then
the method throws an IllegalStateException indicating that the tamagotchi cannot eat.
Otherwise, the method generates the following:
– a random double between 0 (included) and 0.5 (excluded) representing the energy gained
by eating.
– a random integer between 1 (included) and 4 (excluded) representing the experience gained
from eating.
The method uses the two random numbers to update the corresponding attributes. It then
increases the number of meals consumed by 1, and it displays a message indicating the updated
energy and experience values of the tamagotchi. For example, when called, the method might
display the following:
Nom nom nom
Mimitchi has now 137 xp, and 8.91 energy.
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• The sleep() method
This method takes no inputs. It simply displays that the tamagotchi is now going to sleep and
it resets its energy back to MAX ENERGY.
• The toString() method
This method returns a String consisting of all the information regarding a Tamagotchi. For
instance, if you display what this method return, you might see the following:
Name: Mimitchi
Level: 2
Energy: 10.00
XP: 137
Meals: 3
Toys: [Trooper the yellow stuffed cat, Mary the blue ball]
(c) (25 points) FileIO
FileIO.java must contain the following private static methods:
• loadToys() method.
This method takes as input a filename as a String parameter, and returns an ArrayList of
Toys.
The loadToys method must use a FileReader and a BufferedReader in order to open the
file specified by the filename. Declare the IOException in the header of the method using the
throws keyword.
You can assume that the files that loadToys receives as input have all the same format: each
line consists of a toy name, color, type, and experience points, each separated by a tab character
(\t).
An example of a file containing toys is found in the provided files as mimitchiToys.txt.
Using the information on each line and the method createToy() from the Toy class, create
all the necessary Toys, and store them all in the ArrayList that will then be returned by the
method.
In this method you should catch the IllegalArgumentException that might be raised by the
method createToy. In the catch block simply display a message stating that the format of the
file is incorrect. In such a case, the method should return an empty ArrayList. (NOTE that
empty does not mean null!)
• saveToys() method.
This method takes as input an ArrayList of Toys as well as a String representing a filename.
The saveToys() method must use a FileWriter and a BufferedWriter in order write to the
file specified by the filename. Make sure to handle the IOException using a try-catch block
and print a meaningful message if necessary.
The format of the file created by saveToys() should match the format that is expected by
loadToys(). (See the description given above)
This method should return true if the file was successfully written, false otherwise.
FileIO.java must also contain the following public static methods:
• loadTamagotchi() method.
This method takes as input a filename as a String parameter, and returns a Tamagotchi.
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The method must use a FileReader and a BufferedReader in order to open the file specified by
the filename. Declare the IOException in the header of the method using the throws keyword.
You can assume that the files that loadTamagotchi receives as input have all the same format:
they contain 6 lines, with the following information about a tamagotchi
– Name
– Level
– Energy
– Experience
– Meals consumed
– The name of a file containing all its toys
An example of such files is the mimitchi.txt which is provided with the assignment. Use the
readLine() method of the BufferedReader to retrieve the content of the file. Use the information retrieved to create and return the appropriate object of type Tamagotchi.
• saveTamagotchi() method.
This method takes as input a Tamagotchi, a String representing the filename in which the
tamagotchi should saved, and a String representing the filename in which the tamagotchi’s
toys should be saved.
The saveTamagotchi() method must use a FileWriter and a BufferedWriter in order write
to the file specified by the filename. Make sure to handle the IOException using a try-catch
block and print a meaningful message if necessary.
The format of the file created by saveTamagotchi() should match the format that is expected
by loadTamagotchi(). (See the description given above) Note that method should use its third
input to write the last line of the file. More over, the method should also make sure that all
the toys belonging to the specified Tamagotchi will be saved to the appropriate file.
This method should return true if the files was successfully written, false otherwise.
(d) (0 points) Playground (Optional)
The Playground class has only one public static method called play(). You are highly encouraged to add private helper methods that allow you to organize your code well.
The play() method takes no inputs. The method should do the following:
• Create a Scanner object to take input from the user.
• Welcome to user to the game and ask for the name of the tamagotchi they’d like to play with.
• Assume that the file containing the information regarding the tamagotchi is named as follows:
“name.txt”, where “name” is what the user provided as input and the file name contains
only lower case letters of the alphabet. For instance, if the user provides you with the name
“Mimitchi”, then the program should be looking for a file named “mimitchi.txt”.
• The program uses the name of the file to load the correct tamagotchi. If something goes wrong
while doing so, then the program creates a new tamagotchi with the specified name using
directly one of the tamagotchi constructors.
• The program then displays the info regarding the tamagotchi and asks the user to enter a
command between play, feed, and sleep.
• Until the user enters the command “sleep”, do the following
– If the user entered play then ask the user to also enter the playing mode (an integer between
1 and 2) and call the appropriate method from the Tamagotchi class.
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– If the user enters feed call the appropriate method from the Tamagotchi class.
– If the user enters any other command print a message that the input was not recognized.
– If an IllegalStateException was raised by any of the methods, then the program should
not crash and instead display the message from this exception. (Note, that you can use the
method getMessage() on an object of type Exception to retrieve the appropriate message)
– If an InputMismatchException was raised (because the user entered something that was
not a int when asked for an int, for instance), then the program should not crash and
instead display an appropriate message.
– Ask the user for the next command.
• If the program gets out of the loop it’s because the command sleep was entered. The program
should then call the appropriate method and save the current state of the Tamagotchi to a file
named “name.txt” (for example “mimitchi.txt”) and its toys to a file named “nameToys.txt”
(for example “mimitchiToys.txt”)
On the next page you can find some sample output produced by running the play() method from the
main method of the Playground class with no seeds in the constructors of the Random objects. The
first output was generated when I did not have any text file containing information about a Tamagotchi.
The second one was ran right after the first one. The txt files provided to you with this assignments are
the text files created by my program after the second run.
Note that for this assignment, your output doesn’t need to match exactly the samples provided. You
are free to change these statements as you wish, as long as the required information still appear.
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Second output:
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What To Submit
Please put all your files in a folder called Assignment5. Zip the folder (DO NOT RAR it) and submit it in
MyCourses. Inside your zipped folder, there must be the following files. Do not submit any other files,
especially .class files. Any deviation from these requirements may lead to lost marks.
Toy.java
Tamagotchi.java
FileIO.java
Playground.java (optional)
Confession.txt (optional) In this file, you can tell the TA about any issues you ran into doing
this assignment. If you point out an error that you know occurs in your problem, it may lead
the TA to give you more partial credit. On the other hand, it also may lead the TA to notice
something that otherwise they would not.
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