Interview Task: Java exercise to test basic Java skills

Here is a problem to test following basic Java skills, with increasing difficulty. Depending on what skills are expected from you.

1. OOPS concepts
2. Code Design
3. Knowledge of Java classes
4. Collections
5. J2EE

Interview Tasks

Task 1
Create an application that maintains information of all students in a class.
The information of each student includes Name, Age and Roll number.

The application should be able to do the following, through a console: (No need for UI)

1. Add a new student information
2. Delete a student information
3. Edit Student information -- Roll number should not be editable
4. List all students in a class

--While evaluating the solution, check what are the Interfaces, abstract classes are created and the reasons to do so. Which collection is used to store the list of students. How do you ensure a student is not added twice.

Task 2

Now functionality that will allow users to be sorted alphabetically by Name.
Also add another functionality that will allow users to be sorted by roll number.

-- Check usage of Comparator , Comparable and methods used to sort the Students.

Task 3 (Checking J2EE knowledge)

Create a web application which will allow the functionalities in task 1 to be done from browser.

-- Which framework is used to do this, and what was the reason to use that.

Task 4

Create a login page and allow user to be authorized. Only one user needs to be created.

-- Check how is authentication done, where are the credentials stored ?

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