CS202 Assignment 2
File I/O, ArrayList, Classes and Interface (Comparable)
Due: 11:59pm 05/26/2023(Friday)
In this assignment, you are asked to read from a file “student_hobbies_JU.txt”
which contains your classmates’ names and their hobbies. You will then need to
find out, for each of your hobbies, how many people in your class share the same
hobby with you.
You are given a zipped project folder AS2_ArrayList_FileIO. You will need to
import (导入) this project into your workspace. The project folder includes the
following two important files:
1. “student_hobbies_JU.txt”
This file contains student names and their hobbies. The following example
shows the first several lines of this file.
Your program will be reading from this file and reporting how many of your
classmates share the same hobbies with you. See the following example running
results.
2. AppDriver.java,
This file contains the main() and includes the following four tasks.
• Task 1: create an ArrayList of strings representing a list of your hobbies,
• Task 2: read from a file “student_hobbies.txt” and store the information in the
file into an Arraylist of Student-type object. You will need to create a Student
class for this.
• Task 3: Sort the list of students by ascending order of names.
• Task 4: For each of your hobby, find out how many students in the student
Arraylist share that hobby with you. An example running result is given in
Figure 2.
This AppDriver.java file contains compile errors because of the missing
method definitions, for example, createHobbies(), readFile(), and
findSharedHobbies(). Do not change the main(). Just add definitions of the
above methods to your program. Specifically, create createHobbies() for Task
1, readFile() for Task 2, and findSharedHobbies() for Task 4. For the sorting
inTask 3 to work appropriately, you will need to have the Student class
implement the Comparable interface.
Example running results
Hints
1. Format output:
The following is an example illustrating formatting output. You will need it for task 2
and 3.
public class Main {
public static void main(String[] args) {
String string1 = "Hello";
String string2 = "World";
String string3 = "Java";
System.out.println(String.format("%-10s %-10s %-10s", string1, string2, string3));
}
}
Submission requirements:
1. Submit your zipped project folder. If you use Eclipse, zip up your project folder, for
example, C:\Download\CS202_workspace\FinalProject , not the workspace folder,
for example, C:\Download\CS202_workspace , and submit it to canvas.
2. A screenshot of your running result. (png, jpg, pdf, or docx)
3. Make sure your code is free of compile errors. A project with compile errors in it will earn
you a very low grade.
4. Follow the Java style guide (Files/ASSIGNMENTS/JavaStyleGuide.pdf) and comment
your code whenever necessary.
5. Refer to (Files/AQuickGuide2Eclipse.pdf) for how to import an existing project into
Eclipse, how to open a workspace, etc.
Academic Honesty:
Your code must be your own. Any format of sharing code is not allowed and is considered
plagiarism.