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Project COMP 4A: PetOwner and PetDog
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Due: Monday, February 13, 2012 by 11:59 PM
Deliverables:
The following project files must be submitted to the graded assignment in Web-CAT by the due date
and time specified above (see the Lab Guidelines for information on submitting project files). You
should plan to start on the project not later than Wednesday in lab, and you should make sure that your
files are successfully submitted to the ungraded assignment in Web-CAT during lab on Wednesday.
Projects sent via e-mail past the deadline at 11:59 PM will not be accepted without a universityapproved excuse.
Files to submit to Web-CAT:
PetDog.java
PetOwner.java
PetOwnerApp.java
Overview:
You have been requested to create a project to record pet owners and their pets information. For this
purpose, you need to design and implement three classes PetDog, PetOwner, and PetOwnerApp:
(1) the PetDog class stores pet dogs basic information and includes methods to set and get individual
values; (2) the PetOwner class stores pet owners basic information, includes methods to set and get
his/her own information also has methods to change his dogs name and estimate the cost of keeping
the dog; and (3) the PetOwnerapp class has a main method that creates PetDog and PetOwner objects
and generally tests their respective classes.
Note: Be sure that all three of your Java files are in the same folder.
PetDog.java
Requirements: Create a PetDog class that stores pet dogs basic information and also includes
methods to set and get individual values.
Design: The PetDog class has fields, a constructor, and methods as outlined below.
(1) Fields (or instance variables): name and breed which are String objects, age which is an int,
weight which is a double, and owner which is a String object. These instance variables should
be private so that they are not directly accessible outside the PetDog class.
(2) Constructor: Your PetDog class must contain a constructor that accepts four parameters
representing the pets name, breed, age, and weight. Below is an example of how the constructor
could be used to create PetDog object:
PetDog myPet = new PetDog("Piper", "Pekingese", 2, 12.25);
COMP 1210
Project 4A: PetOwner and PetDog
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(3) Methods: Usually a class provides methods to access (or read) and modify each of its instance
variables (known as get and set methods) along with any other required methods. The methods
for PetDog are described below.
o
getName: accepts no parameters and returns a String representing the pets name. The pets
name can be given when the object is created or set up by the method setName.
o
setName: takes a String parameter and returns a boolean. If the string parameter (the new
pets name) is null, then the method returns false and the new name is not set. Otherwise, the
new name is set to the parameter value and the method returns true.
o
getBreed: accepts no parameters and returns a String representing the pets breed. The
pets breed is given when the object is created.
o
getAge: accepts no parameters and returns a int representing the pets age, which can be set
up by the method setAge.
o
setAge: takes a int parameter and returns a boolean. If the int parameter (the pets age) is
negative number, then the method returns false and the age is not set. Otherwise, the age is
set to the parameter value and the method returns true.
o
getWeight: accepts no parameters and returns a double representing the pets weight.
o
setWeight: takes a double parameter and returns a boolean. If the double parameter (the
pets weight) is negative number, then the method returns false and the age is not set.
Otherwise, the age is set to the parameter value and the method returns true.
o
getOwner: accepts no parameters and returns a String representing the owners name.
Owners name is the setOwner method.
o
setOwner: takes a String parameter and returns a boolean. If the String paramter (the
owners name) is null, then the method returns false and the owners name is not set.
Otherwise, the name is set to the parameter value and the method returns true.
o
toString: returns a String containing the pets name and breed on the first line, followed
by the pets basic information as shown below:
Piper (Pekingese)
Age: 2
Weight: 12.25 lbs
Owner: Patty
Code and Test: As you implement your PetDog class, you should compile and test it using
interactions. For example, as soon you have implemented and successfully compiled the constructor,
you should create an instance of PetDog in interactions (see the example above). Then after you
implement and compile one or more methods, create a PetDog object and invoke each of the methods
you added or changed to make sure everything is working as intended. [Hint: When using
interactions, you can use the Up-Arrow to avoid retyping previously entered interactions.]
COMP 1210
Project 4A: PetOwner and PetDog
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PetOwner.java
Requirements: Create the PetOwner class that stores pet owners basic information, includes
methods to set and get his/her own information also has methods to change his dogs name and
estimate the cost of keeping the dog.
Design: The PetOwner class has fields, a constructor, and methods as outlined below.
(1) Fields: name and address which are String objects, and myDog which is a PetDog object.
These instance variables should be private so that they are not directly accessible outside the
PetOwner class.
(2) Constructor: Your PetOwner class must contain a constructor that accepts two String parameters
representing the pet owners name and address. Below is an example of how the be constructor
could used to create PetOwner object:
PetOwner myOwner = new PetOwner("Patty Liu", "Auburn, AL");
(3) Methods: Usually a class provides methods to access (or read) and modify each of its instance
variables (known as get and set methods) along with any other required methods. The methods
for PetOwner are described below.
o
getName: accepts no parameters and returns a String representing the owners name. The
owners name can be given when the object is created or set up by the method setName.
o
setName: accepts a String parameter and returns a boolean. If the string parameter (the new
pet name) is null, then the method returns false and the new name is not set. Otherwise, the
new name is set to the parameter value and the method returns true.
o
getAddress: accepts no parameters and returns a String representing the owners address.
Owners address can be set using the method setAddress.
o
setAddress: accepts a String parameter and returns a boolean. If the string parameter is
null, then the method returns false and the new address is not set. Otherwise, the new
address is set to the parameter value and the method returns true.
o
getMyDog: returns the PetDog stored in the myDog field in the PetOwner object.
o
setMyDog: accepts a parameter of type PetDog and sets myDog in the PetOwner object.
o
changeDogName: accepts a String parameter with no return value. This method changes
pet dogs name using the setName method in PetDog class.
o
estimatePetCost: returns a double representing the estimated cost of keeping the dog
where the cost of keeping a dog depends on the weight and age of the dog.
The estimate of pet cost per month = dog food + other expenses.
COMP 1210
Project 4A: PetOwner and PetDog
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The cost of dog food per month is calculated as (weight of dog 0.7).
The other monthly expenses, which include costs for snacks, toys and medical expenses,
are calculated based on age: younger than 2 years old average cost is 100 per month; 2
years to 9 years old (but not included 9) average cost is 40 per month; 9 years and older
the average cost is 120 per month.
o
toString: returns a String containing the pet owners basic information formatted as
shown below:
Patty Liu
Piper (Pekingese)
Age: 2
Weight: 12.25 lbs
Owner: Patty Liu
Auburn, AL
Code and Test: As you implement your PetOwner class, you should compile and test it using
interactions. For example, as soon you have implemented and successfully compiled the constructor,
you should create an instance of PetOwner in interactions (see the example above). Then after you
implement and compile one or more methods, create a PetOwner again and invoke each method on it
to make sure it is working as intended. Note that youll need to create an instance of PetDog before
you invoke the setMyDog method since this method takes a PetDog as a parameter.
PetOwnerApp.java
Requirements: Create a PetOwnerapp class with a main method creates PetDog and PetOwner
objects and generally tests their respective classes.
Design: A class with a main method utilizes the PetDog and PetOwner classes by having the user
enter the pets name, breed, age and weight, followed by the owners name and address. Your
program then creates a PetDog object and a PetOwner object, makes the PetDog object the pet of the
PetOwner, and then prints out the owner. Your program should now offer the user a chance to
change the pet dogs name and print out a confirmation. The last thing your program needs to do is
allow the user to optionally print the monthly cost of owning the dog. See the example of input and
output on the following page for formatting details. Replace the prompts in italics with your own
words.
COMP 1210
Project 4A: PetOwner and PetDog
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Example:
Line # Program input/output
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Prompt
Prompt
Prompt
Prompt
Prompt
Prompt
user
user
user
user
user
user
for
for
for
for
for
for
the
the
the
the
the
the
name of his/her pet dog: Piper
breed of the dog: Pekingese
age of the dog: 2
weight of the dog: 12.25
name of the owner: Patty Liu
address of the owner: Auburn, AL
Patty Liu
Piper (Pekingese)
Age: 2
Weight: 12.25 lbs
Owner: Patty Liu
Auburn, AL
Prompt whether the user wants to change the dog name(Y/N): Y
Prompt user for the new name: Jenny
The name of your dog has been changed to Jenny.
Prompt user whether to calculate the estimated cost (Y/N): Y
Your dog bills will be approximately $48.58 per month.
Code & Test: Your program should declare local variables for a PetDog object, a PetOwner object
and all input data. Your program should use the DecimalFormat class to format the estimated cost so
that it is rounded to two decimal digits and includes a leading dollar sign ($).
jGRASP Project and UML Class diagram All three of
your Java files should be in the same folder. You should also
create a jGRASP project in this folder and add your Java files
to it. This will facilitate submission to Web-CAT. After you
have created the project, you can generate the UML class
diagram for your project (as shown at left) by clicking on the
UML symbol for project in the Browse tab. After the
diagram is generated, rearrange the classes so that class with
main is at the top. The purpose of the UML class diagram is
to show the dependencies among your classes: PetOwnerApp
UML Class Diagram
depends on PetOwner and PetDog; PetOwner depends on
Petdog; and PetDog does not depend on either of the other classes. These dependencies dictate the
order of compilation (e.g., you can only compile PetOwner after you have successfully compiled
PetDog).