Java programming

1

CIS 265 Data Structures and Algorithms

Assignment 5, 100 points

Due: 12:25pm, Mar. 10, 2021

I. General Description

In this assignment, you will create a Java program to read undergraduate and graduate students from an input

file, and write them in reverse order to an output file.

1. The input file name and the output file name are passed in as the first and second arguments at command
line, respectively. For example, assume your package name is FuAssign5 and your main class name is

FuAssignment5, and your executable files are in “C:\Users\2734848\eclipse-workspace\CIS 265

Assignments\bin”. The following command line will read from a local file “students.txt” and write to a

local file “students_reversed.txt”:
C:\Users\2734848\eclipse-workspace\CIS 265 Assignments\bin > java FuAssign5.FuAssignment5
students.txt students_reversed.txt

2. You need to specify the command line arguments if you use jGrasp or Eclipes. I will show you on jGrasp
on Wed.

3. The parameter String[] args in the main method contains the command line arguments, where args[0]
contains the first argument. For example, in the previous command, args[0] contains students.txt, and

args[1] contains students_reversed.txt.

4. If the program is run with incorrect number of arguments, your program must print an error message and
exit. The error message must show correct format to run your program, e.g., “Usage:

FuAssign5.FuAssignment5 input_file output_file” where FuAssign5 is the package and FuAssignment5 is

the main class.

5. Each line in the input file represents a student. There are 5 fields in each line: name, id, gpa, “graduate” or
“undergraduate”, isTransfer (for undergraduate) or college (for graduate). The fields are separated by

comma, “,”. For example, the input file students.txt file may contain:

Michelle Chang,200224,3.3,graduate,Cleveland State University
Tayer Smoke,249843,2.4,undergraduate,false
David Jones,265334,2.7,undergraduate,true
Abby Wasch,294830,3.6,graduate,West Virginia

6. The program will read the lines and create undergraduate students or graduate students accordingly. The

students are added to an ArrayList.

7. The program then writes the list of students in reserve order to the output file.
8. Given the previous input file students.txt, the output file, students_reserved.txt, will be:

Abby Wasch,294830,3.6,graduate,West Virginia
David Jones,265334,2.7,undergraduate,true
Tayer Smoke,249843,2.4,undergraduate,false
Michelle Chang,200224,3.3,graduate,Cleveland State University

II. Implementation Requirements

The program must implement a main class and three student classes (Student, UndergradStudent, GradStudent).

• You may reuse the code from previous assignments.

2

• However, the Student class must be declared as an abstract class now. It must also have an overloaded
printStudent(PrintWriter output) method. The method will write student’s information to the output file

using the PrintWriter output.

• Accordingly, the UnderGradStudent and GradStudent classes must also have an overloaded
printStudent(PrintWriter output) method. They must use the superclass’ method to write student’s

information. The UnderGradStudent’s printStudent(PrintWriter output) writes “undergraduate” and

isTransfer after that. The GradStudent’s printStudent(PrintWriter output) writes “graduate” and college

after that.

• The UML class diagram should be as follows.

• All classes must be in the same package. The package name must start with your last name. For example, if
your last name is “Fu”, your package name must start with “Fu” such as “FuCIS265AS3”, “FuAS3”, etc.

• Your main class file name must start with your last name. For example, if your last name is “Fu”, your main
class file name must start with “Fu” such as FuAssignment5.java.

• Since I/O exceptions are checked exceptions, your program must handle exceptions. You may use the
try/catch or throw IOException. To throw exceptions, you declare it as:

public static void main(String[] args) throws IOException {

• You must create an ArrayList of Students in the main class:
import java.util.ArrayList;
ArrayList students = new ArrayList<>();

The ArrayList students will store all Student objects created, both undergraduate students and graduate
students.

• The Student class must have a constructor that takes a name, an id, and a gpa, to create a Student object.

• The UndergradStudent class must have a constructor that takes a name, an id, a gpa, and a transfer status to
create an UndergradStudent object. The constructor must call the Student’s constructor using super.

• The GradStudent class should must a constructor that takes a name, an id, a gpa, and a college to create a
GradStudent object. The constructor must call the Student’s constructor using super.

• The Student class must have a public method printStudent(PrintWriter output) that writes the student’s name,
id, and gpa to the PrintWriter output.

Student

-name: String

-id: int

-gpa: float

+Student()

+Student(name,id,gpa)

+printStudent():void

+getID():int

+printStudent(PrintWriter output):void

UndegradStudent

-boolean: isTransfer

+UndergradStudent(name,id,gpa,isTransfer)

+printStudent():void
+printStudent(PrintWriter output):void

GradStudent

-college:String

+GradStudent(name,id,gpa,college)

+printStudent():void
+printStudent(PrintWriter output):void

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• The UndergradStudent class must override the printStudent(PrintWriter output) method. It must write the
student’s name, id, gpa, and transfer status to the PrintWriter output. It should call the Student’s

printStudent(PrintWriter

output) to write student’s name, id, and gpa.

• The gradStudent class must override the printStudent(PrintWriter output) method. It must write the student’s
name, id, gpa, and college to the PrintWriter output. It should call the Student’s printStudent(PrintWriter

output) to write student’s name, id, and gpa.

• Your program must use dynamic binding to invoke the correction printStudent(PrintWriter output) method.

• Your program must close both input and output files after they are done.

• You can assume that input file has the correct format. You will earn bonus points for handling incorrect
input formats.

III. Submission

This is an individual assignment. Each student needs to submit the source code files of the Java program on

Blackboard.

1. Put all you Java files in a folder. Please name the folder after your package name, for example,
FuAssign5. Compress the folder into a .zip file and submit the .zip file.

2. You need to only submit the source code, i.e., the Java files.
3. You may submit multiple time. Your most recent submission before the deadline will be graded.

IV. Grading
1. A program that does not run will receive 0 point.
2. There is a 10-20 points deduction for each major error, e.g., missing a student in the output.
3. There is a 1-9 points deduction for each minor error, e.g., a spelling error in printed message.
4. A program that does not follow the guidelines will lose 1-10 points.
5. Any type of cheating is not tolerated. You may be asked to explain your program in person.

V. Bonus features (optional)

If a line in the input file has incorrect format, your program will print an error message with the line, skip the

line and continue. The following are possible formatting errors your program can handle:

1. (2 points) if the line does not have 5 fields;
2. (2 points) if the id is not an integer;
3. (2 points) if the gpa is not a double;
4. (2 points) if the 4th field is not “undergraduate” or “graduate”;
5. (2 points) if the 5th field for an undergraduate student is not true or false.

For example, for the following lines in the input file,

Sam Jackson,215.22,3.9,graduate,Ohio State University
Sam Jackson,215443,22af,graduate,Ohio State University
Sam Jackson,215443,3.9,graduate
Sam Jackson,215443,3.9,graduate,Ohio State University,cleavland
Sam Jackson,215443,3.9,nondegree,Ohio State University
Lady Gaga,230940,3.1,undergraduate,unknown

You program will print :

Invalid input: Sam Jackson,215.22,3.9,graduate,Ohio State University

4

Invalid input: Sam Jackson,215443,22af,graduate,Ohio State University
Invalid input: Sam Jackson,215443,3.9,graduate
Invalid input: Sam Jackson,215443,3.9,graduate,Ohio State University,cleavland
Invalid input: Sam Jackson,215443,3.9,nondegree,Ohio State University
Invalid input: Lady Gaga,230940,3.1,undergraduate,unknown

The incorrect lines will be ignored and not written to the output file. The correctly formatted lines should be

handled as usual.