Description
Coursework Aims
This coursework allows you to demonstrate that you:
• Understand how to construct simple classes and implement methods.
• Are able to take simple pseudo-code descriptions and construct working Java code from them.
• Can write a working program to perform a complex task.
• Have an understanding of object-oriented programming.
• Can correctly use polymorphism and I/O.
• Can write code that is understandable and conforms to good coding practice.
Contacts
General programming queries should be made to your demonstrator in the timetabled labs.
Queries about the coursework specification should be made to Jian Shi (Jian.Shi@soton.ac.uk).
Any issues that may affect your ability to complete the coursework should be made known to Jian Shi
(Jian.Shi@soton.ac.uk) or Son Hoang (T.S.Hoang@ecs.soton.ac.uk), ideally before the submission deadline.
Instructions
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ECS Java Training School
Specification
The aim of this coursework is to construct a simple simulation of a Java training school. This school will
admit students and they will receive training by a team of specialist instructors.
You are not required to have any knowledge of running and managing a training school in order to
complete this coursework and no management accuracy is claimed in the representation of marketing
practices presented here.
The ECS Java training school may bear some superficial similarities to a real school but is grossly simplified
and in most cases likely to be quite different to how a real school might work.
Your task is to implement the specification as written.
In some cases, specific names are defined or specific properties given for classes. This is mainly to ensure
that we can easily read your code, and find the parts that are most relevant to the marking scheme. You
will not gain marks for deviating from the specification in order to increase the realism of the simulation. In
fact, it may cost you marks and make it harder to assess what you have written. In some cases we wish to
know that you can use specific Java constructs, so if it specifies an ArrayList then we want to see you use
an ArrayList. There might be other ways of implementing the same feature but we are trying to assess
your ability to use specific constructs. Where the specification is less explicit in the way something is
implemented (for example, by omitted what data types to use) you are free to make your own choices but
will be assessed on how sensible those choices are. Comments in your code should explain the choices you
have made.
An FAQ will be kept on the notes pages of answers that we give to questions about the coursework. If
issues are found with the specification it will be revised if necessary. If questions arise as to how certain
aspects might be implemented then suggestions of approaches may be made but these will be suggestions
only and not defined parts of the specification.
How the ECS Java training school works
For this coursework you are expected to follow the specification of the school, students and instructors as
set out below. This will not correspond exactly to a real school or instructors in reality but we have chosen
particular aspects for you to model that help you to demonstrate your Java programming.
The school offers training courses on various Java’s related subjects. Some examples of subjects are
showed in
Table 1. Each subject has a unique ID and belong to some area of specialism. The duration for the course
associated with each subject is specified. The specialism determines the type of instructors that can deliver
the course. For example, for the subject titled “Basics (variables, conditionals, methods, loop, etc.)” (with ID
“1”), the duration for a course covering the subject is 5 days. Furthermore, the subject belongs to
Specialism “1” and can be taught by any teachers.
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Table 1. Example of Subjects
There are a number of concepts, people, and procedures that contribute to this simulation. For our
purposes these include:
Students: Students will be admitted to the school to study a number of subjects. These subjects need to be
taught by the instructors. A student can only enrol to at most ONE course at a time. Once the students have
graduated they can leave the school.
Courses: The school will create courses to teach different subjects. Each course is associated with exactly
ONE subject. Each course will have a maximum 3 students and must be taught by an instructor.
Instructors: The school will be staffed by a number of instructors. The instructors may have particular
specialisms that let them teach particular subjects. Some subjects can only be taught by instructors with
the right specialism. An instructor will teach at most ONE course at a time.
School: For our purposes a school will manages the courses, students, and instructors.
Administrator: The school administrator is in charge of registering/deregistering students and instructors
to the school.
The next sections will take you through the construction of the various required concepts. You are
recommended to follow this sequence of development as it will allow you to slowly add more functionality
and complexity to your final simulation. The first steps will provide more detailed information to get you
started. It is important that you conform to the specification given. If properties and methods are written in
Subject ID Specialism Duration Instructor
Basics (variables,
conditionals, methods,
loop, etc.)
1 1 5 days Any Teacher
Lab 1 (Basics) 2 2 2 days Any Teacher or
Demonstrator
Arrays 3 1 3 days Any Teacher
Algorithms 4 1 1 day Any Teacher
Testing and Debugging 5 1 3 days Any Teacher
Lab 2 (Advanced) 6 2 2 days Any Teacher or
Demonstrator
Object-Oriented 1 (class,
inheritance, etc.)
7 3 6 days OOTrainer
Object-Oriented 2
(encapsulation, exception,
etc.)
8 3 7 days OOTrainer
Lab 3 (Object-Oriented) 9 2 3 days Any Teacher or
Demonstrator
Graphics 10 4 5 days GUITrainer
Controllers 11 4 2 days GUITrainer
Lab 4 (GUI) 12 2 3 days Any Teacher or
Demonstrator
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red then they are expected to appear that way for the test harness and our marking harnesses to work
properly.
Part 1 – The Subject and Course classes
Subject
The first class you will need to create is a class that represents a Subject. The
properties for the Subject class that you will need to define are:
• id – this is the unique ID of the subject,
• specialism – this is the specialism ID of the subject.
• duration – this is the duration (number of days) required for any course
covering the subject.
Define these as you think appropriate, and create a constructor that initialises them. Define accessor
methods getID(), getSpecialism(), and getDuration() to return the properties accordingly.
Now define the following additional property:
• description – this is the string description of the subject.
Define the accessor and mutator methods getDescription() and setDescription(String) for
getting and setting this property accordingly.
Course
The second class you will need to create is to represent a Course. The properties of the course are:
• subject – this is the subject associated with the course.
• daysUntilStarts – this is the number of days until the course starts
• daysToRun – this is the number of days that the course still has to run.
Define these as you think appropriate, and create a constructor Course(Subject, int) that initialises
them. Note that the initial value for daysToRun depend on the input Subject. Implement getSubject()
method to return the subject associated with the course.
Implement the accessor method getStatus() to return the status of a course as follows:
• if the course has not started, then return the negative of the number of days until the course
starts.
• if the course is currently running, then return the number of days left until the course finishes.
• If the course has finished, then return 0.
Finally, define method aDayPasses() to advance one day for the course. The method must change the
value of properties daysUntilStarts and daysToRun accordingly.
BY THIS STAGE you should have a Subject class, and a Course class connected to the
Subject class.
Figure 1. Subjects and Courses
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You can now test your Subject and Course classes by creating a main method and to create some objects
of these classes. You call aDayPasses() method on the Course objects and check how their status
changes.
Part 2 – The Student class
Person
The first step in this part is to create is an class that represents a Person. The Person
class will be the basis for your Student and Instructor classes. This is an class that
defines the basic properties and methods that all the different people classes will use.
The properties that you will need to define are:
• name – this is the name of the person,
• gender – this defines whether the person is male (‘M’) or female (‘F’),
• age – this says how old the person is in years.
Define these as you think appropriate, and create a constructor that initialises them.
The Person class will also need to define some methods:
• getName() – returns the name of the person,
• getGender() – returns the gender (as a char) of the person,
• setAge(int) – set the age of the person,
• getAge() – returns the age of the person.
Student
To model people in different roles, you will use inheritance. Start off by creating
Students.
Define your second class, Student, that inherits from the Person class. An important
property of Students are the certificates for the subjects that they have taken.
• certificates – this is the collections of subject IDs that the student has
obtained.
Use an ArrayList to represent the certificates of a student. Create a constructor to initialise this property
accordingly. To manage the student certificates, we will need a number of methods.
• graduate(Subject) – this adds the ID of the subject to the collections of certificates.
• getCertificates() – this returns the ArrayList of certificates obtained by the students.
• hasCertificate(Subject) – this checks whether or not the student has already obtained the
certificate for the input subject.
We now need to connect the Student class with the Course class. Each course needs to maintain the
collection of enrolled students. Define an appropriate property in the Course class and implement the
following method.
• enrolStudent(Student) – this adds the student to the collection of enrolled students. The
method return a boolean indicating if the registration is successful or not. Reasons for
unsuccessful registration include:
o The course is full (each course has a maximum of 3 students).
o The course has already started.
• getSize() – this returns the number of students enrolled in the course.
• getStudents() – this returns the Student[] array of students enrolled in the course.
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Finally, modify the aDayPasses() method to ensure that if the course finishes then issues the certificate
for the course’s subject to all the students in the course.
BY THIS STAGE you should have an Person class, and the first subclass of Person: Student
connected to the Course class. Note that we will ensure that a student enrols to at most one
course at a time later.
Figure 2. Students and Courses
You can now test your new Student class by creating a main method and to create some Subject,
Course, and Student objects. You can register the students to the courses and call aDayPasses() method
on the Course objects and check how the students obtain the certificates.
Part 3 – The Instructor classes
Instructors
To model the various types of Instructors you will need for your School (Teachers,
Demonstrators, OOTrainers and GUITrainers) you will need to continue to use
inheritance.
The diagram in Figure 3 shows you how the classes that you will create are related to
each other. As you can see, both Student and Instructor inherit from Person.
Teacher and Demonstrator are subclasses of Instructor, and OOTrainer and
GUITrainer are subclasses of Teacher.
Figure 3. Inheritance Hierarchy of People
The first class to create is an abstract Instructor class. This is a class that defines the basic properties
and methods that all the different instructor classes will use. The property that you will need to define are:
• assignedCourse – this is the course that is assigned to the instructor.
The Instructor class will also need to define some methods for use by the School.
• assignCourse(Course) – this assigns the input course to the instructor
• unassignCourse() – this removes the assigned course to the instructor
• getAssignedCourse() – this returns the assigned course to the instructor if any.
Define an abstract method canTeach(Subject) which returns a boolean. This method will be
overridden by the other instructor sub-classes depending on their specialism. As we progress you may
choose to add additional methods to your classes.
Teachers, Demonstrators, OOTrainers, and GUITrainers
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Define the sub-classes of Instructor according to the hierarchy in Figure 3. In particular, each of the subclasses, namely, Teacher, Demonstrator, OOTrainer and GUITrainer must implement the
canTeach(Subject) method according to the following rules related to the subject’s specialism IDs.
• Teacher can teach subjects with specialisms 1, 2.
• Demonstrator can teach subjects with specialism 2.
• OOTrainer can teach subjects with specialisms 1,2, 3
• GUITrainer can teach subjects with specialisms 1,2,4
To connect the Instructor class to the Course class, follow the steps below (you might want to add
extra properties to the Course class to support the implementation of these methods):
• add a method setInstructor(Instructor) to the class. This method should have a return
value indicating whether the assignment is successful, i.e., the instructor can teach the course,
• add a method hasInstructor() to return whether or not the course has an instructor,
• modify the aDayPasses() method to cancel the course when the course starts without any
instructor (you might need to add some property to the course) or students,
• in aDayPasses() method, remember to unassign the instructor from the course when the course
finishes,
• add a method isCancelled() to return weather or not the course has been cancelled.
• Remember to release the students (if any) and the instructor (if any) from the course when the
course is cancelled.
BY THIS STAGE you should have an additional Instructor class, and various sub-classes,
connected to the Course class.
You can now test your new Instructor classes by creating a main method and to create some
instructors, courses, and students. You can assign the instructor and students to the courses and call
aDayPasses() method on the Course object and check how the instructors’ status changes.
Part 4 – The School
Our School class is where all our Students are taught and our Instructors work. The
school must have a name. Define the property and appropriate constructor for
initialise that. The school keeps information about the Subjects, Courses, Students,
and Instructors. The School will need a number of methods. These should include:
• add(Student) – this adds a new student to the School.
• remove(Student) – this removes a student from the School
• getStudents() – this returns the students in the school.
Define similar methods for Subject, Course, Instructor accordingly, i.e., add(Subject),
remove(Subject), getSubjects(), etc. Furthermore, we need to have utility methods for the
simulation of the school.
• toString() – this overrides the method returning a pretty-print string of the school. It should
contain information about subjects, courses, instructors, students and the relationship between
them.
• aDayAtSchool() – this simulates events of a day at school (see below).
We are going to keep our simulation simple and try and avoid any complicated scheduling problems. No
additional marks will be given for having really efficient scheduling systems. You are required to have a very
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simple working process, it is not necessary to make this too complicated. A typical day at the school will
have the following events occur.
• Create new courses: for any topic that does not have an open-for-registration course, create a new
course for that subject to start in 2 days.
• Assign instructors and students to courses. The simplest way to do this is to:
o Look at each course that requires an instructor, and go through the instructors until you
find one that is free (i.e., not already teaching other courses), and can teach the course.
Assign the instructor to the course.
o Look at each students, if they are free, (i.e., not enrolled in any course) go through the
courses until you find one that the student can join (e.g., not already full and the student
has not got the certificate).
• Let the student learn (e.g., call aDayPasses() on each courses.)
• At the end of the day, removes any course that is cancelled or already finished.
You might need to add other properties and methods as appropriate.
BY THIS STAGE you should have implemented School class, connected to the Course,
Student, Instructor classes.
You can now test your new School class by creating a main method and to create some instructors,
subjects, students and add them to the school. Call the aDayAtSchool() method on the school and print
the status of the school to see how it changes. You are advised to get all of this working before attempting
to extend your functionality.
Part 5 – Running the simulation
In order to run our School as a simulation we are going to need a school Administrator. This class will have a
School, will organise the day to day running of the School, i.e. run the simulation itself.
You should create a new class called Administrator. It should have a School instance and have a run()
method which is used to run the simulation.
A typical day for a school administrator will have the following events occur.
• New students will be admitted to the school. Each day will have up to 2 students join the school.
You will need to use a random number generator to decide the number of the students joining the
school. You can do this with the Toolbox class that was provided with the labs, or by using the
methods in the java.util.Random class directly.
• New instructor will join the school. The probabilities for a Teacher, Demonstrator, OOTrainer, and
GUITrainer to join each day are 20%, 10%, 5%, and 5%, respectively. Again, use a random number
generator for this.
• Run the school, i.e., call aDayAtSchool() method of the school.
• At the end of the day, students and instructors might leave the school
o A free instructor (i.e., not assigned to any course) have 20% chance of leaving the school
o If a student obtains the certificates for all subjects, the student will leave the school.
Otherwise, if the student does not enrol in any course, he or she has 5% chance of leaving
the school.
For properties of people, i.e., name, gender, age, you can use the random generator for creating them or
use some fix value.
Define an overloaded version of run() that takes a number of days as a parameter, and simulates that
number of days. After each day it should call report on the school to list information about courses
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(including course status, list of enrolled students), students (certificates, enrolled course if any) and
instructors (assigned course if any).
You can use print statements to record what is happening in your simulation. To slow things down a little,
the following code will help you to pause for half a second between calls if you choose to include it.
try
{
Thread.sleep(500);
run();
}
catch (InterruptedException e)
{
}
BY THIS STAGE you should have implemented Administrator class, connected to a School
You can now test your new Administrator class by creating a main method and to an instance of that
for a School and call the corresponding run() methods.
Part 6 – Reading a simulation configuration file
A good simulation will allow you to set the starting conditions for your simulation and one way of doing this
is for the simulation to read in a simple configuration file. For this step you will need to use your file
handling methods as well as split strings into different component parts.
Our basic configuration file will look like the example below. You may choose to extend this for your
extensions, but for testing purposes your code should accept and use configuration files in this form. Each
line gives information about a school student or an instructor.
school:ECS Java Training School
subject:Basics,1,1,5
subject:Lab 1,2,2,2
subject:Arrays,3,1,4
student:Peter,M,60
student:John,M,22
student:Annabelle,F,31
student:Maggie,F,58
student:Alex,M,23
Teacher:Yvonne,F,55
Demonstrator:Beth,F,45
OOTrainer:Chris,M,62
GUITrainer:Sarah,F,48
The format for the school is
School:name
The format for Subjects is
subject:description,subjectID,specialisationID,duration
The format for Students is
student:name,gender,age
The format for Instructors is
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instructor_type:name,gender,age
Some example simulation files of varying complexity will be placed on the WIKI.
You should modify your main method so that it can take a file on the command line. This will enable you to
start your simulation by taking the name of the configuration file and the duration (number of days) for the
simulation.
java Administrator mySchool.txt 200
When the Administrator receives the configuration, it should read the file a line at a time. For each line
the file will need to identify the Class, create a new class of this type, and set the appropriate parameters
and add it to the School. You may find you need to create specific methods or indeed a helper class, to
parse the configuration file and extract the information that the Administrator needs.
We are placing this code in the Administrator to make it simple, so your simulation is of an
Administrator with a School in it.
You should now have a simulator that runs with an Administrator containing a School which has
multiple Instructors and Students in it.
Exceptions
You should be trying to use exceptions in the construction of your simulator where possible. You should be
catching appropriate I/O exceptions but also might consider the use of exceptions to correctly manage:
• The input of a configuration file that does not conform to the specified file format.
• …
Extensions
You are free to extend your code beyond the basic simulator as described above. You are advised that your
extensions should not alter the basic structures and methods described above as marking will be looking to
see that you have met the specification as we have described it. If you are in any doubt about the
alterations, you are making please include your extended version in a separate directory.
Scheduling can become very complicated very quickly, so we have deliberately not made efficient
scheduling a part of this coursework. Be warned if you attempt to do anything clever in this regard for your
extension.
Some extensions that we would heartily recommend include:
• Implement the prerequisites for subjects and ensures that students can only enrol on a course if
they have all the prerequisites for that course.
• Your Instructors might be able to teach more than one course in a day (up to a certain limit). The
students can enrol in more than on course at a time (up to a certain limit). Modify your instructors,
students and simulation to deal with this.
• Introduce a limit on the number of consecutive days that the students can learn and the instructors
can teach. Once the limit has been reached, the student or the instructor must take a break.
• Depending on the number students, actively hire/fire the instructors accordingly. Introduce the
cost for hiring/firing and maintaining the instructors and optimise the total cost of running a school.
• You might want to extend the configuration file and classes so some of the parameters of the
simulation can be set in the configuration file. This might include some of the details about courses,
students’ enrolment, or instructors’ allocation for instance.
• You might want to allow the simulation to save out the current state of a simulation to a file so that
it can be reloaded and restarted at another time.
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15% of the marks are available for implementing an extension. Any of the above examples would be
suitable, but feel free to come up with one of your own if you like. It is not necessary to attempt multiple
extensions in order to gain these marks. Please describe your extension clearly in the readme file that you
submit with your code.
Space Cadets
You might want to add a GUI to your simulator so that you can visualise the state of the School at any given
moment. No marks are available for a GUI, we put the suggestion forward simply for the challenge of it,
although you can reasonably expect praise and glory for your efforts.
Submission
Submit all Java source files you have written for this coursework in a zip file school.zip. Do not submit
class files. As a minimum this zip will include:
Subject.java, Course.java, Instructor.java, Teacher.java, Demonstrator.java,
OOTrainer.java, GUITrainer.java, School.java, Administrator.java
Also include a text file readme.txt that contains a brief listing of the parts of the coursework you have
attempted, describes how to run your code including command line parameters, and finally a description of
the extensions you have attempted if any. Submit your files by Friday 6th December 2019 16:00 to:
https://handin.ecs.soton.ac.uk
Relevant Learning Outcomes
1. Simple object oriented terminology, including classes, objects, inheritance and methods.
2. Basic programming constructs including sequence, selection and iteration, the use of identifiers,
variables and expressions, and a range of data types.
3. Good programming style
4. Analyse a problem in a systematic manner and model in an object oriented approach
Marking Scheme
Criterion Description Outcomes Total
Compilation Applications that compile and run. 1 20
Specification Meeting the specification properly. 1,2,4 40
Extensions Completion of one or more extensions. 1, 2,4 15
Style Good coding style. 3 25