Attendance System

Project Setup

This is a Java project for Attendance System.

Steps to Run

1. Compile:

   javac src/com/school/main.java

run

java -cp src com.school.main

Session 2: Core Domain Modelling

• Defined Student class with studentId, name, setDetails(), and displayDetails() method.
• Defined Course class with courseId, courseName, setDetails(), and displayDetails() method.
• Utilized arrays of objects in Main.java to manage and display multiple students and courses.
• Introduced basic usage of this keyword.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/Student.java src/com/school/Course.java src/com/school/Main.java (or javac src/com/school/*.java)
3. Run: java -cp src com.school.Main

Part 3: Constructor Initialization & Auto-ID Generation

• Implemented parameterized constructors in Student and Course classes for object initialization.
• Utilized private static member variables for automatic and unique ID generation.
• Demonstrated the use of the this keyword to distinguish instance variables from constructor parameters.
• Changed Course's courseId to int for simpler auto-generation and updated its display.
• Updated Main.java to use constructors and show ID progression.

How to Run (ensure this is up-to-date)

1. Navigate to the project root directory.
2. Compile: javac src/com/school/Student.java src/com/school/Course.java src/com/school/Main.java (or javac src/com/school/*.java)
3. Run: java -cp src com.school.Main

Part 4: Data Encapsulation & Attendance Recording Validation

• Applied encapsulation to Student and Course classes by making fields private and adding public getters.
• Introduced a new AttendanceRecord class with private fields, a constructor, and getters to store attendance data.
• Implemented basic validation in the AttendanceRecord constructor for the attendance status (allowing only "Present" or "Absent").
• Used an ArrayList in Main.java to store and display AttendanceRecord objects.
• Demonstrated retrieving IDs using getters (e.g., student1.getStudentId()) when creating records.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/*.java (or list individual files including AttendanceRecord.java)
3. Run: java -cp src com.school.Main

Part 5: Establishing Students, Teaching & Non-Teaching Staff hierarchy

• Created a base class Person.java with common attributes (id, name), a universal auto-ID generator, and a displayDetails() method.
• Modified Student.java to inherit from Person, using super() to call the parent constructor and overriding displayDetails() to add student-specific info (e.g., grade level).
• Created Teacher.java extending Person, adding a subjectTaught attribute and its own displayDetails().
• Created Staff.java extending Person, adding a role attribute and its own displayDetails().
• Demonstrated creation and display of Student, Teacher, and Staff objects in Main.java.
• Updated AttendanceRecord creation to use the inherited getId() method.
• Added polymorphism demonstration showing how all Person objects can be stored in a Person array and each calls its own overridden displayDetails() method.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/*.java
3. Run: java -cp src com.school.main

Part 6: Interface-Driven Persistence with Storage

• Defined a Storable interface with a toDataString() method.
• Modified Student, Course, and AttendanceRecord classes to implement the Storable interface and provide their specific toDataString() implementations (CSV format).
• Created a FileStorageService class with a saveData(List<? extends Storable> items, String filename) method to write Storable objects to a text file.
• Utilized try-with-resources for safe file handling (PrintWriter, FileWriter).
• Demonstrated in Main.java how to save lists of students, courses, and attendance records to separate files (students.txt, courses.txt, attendance_log.txt).
• Discussed the flexibility provided by interfaces for handling different types of storable objects uniformly.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/*.java
3. Run: java -cp src com.school.main
4. Check the generated files: students.txt, courses.txt, attendance_log.txt.

Part 7: Polymorphic Behaviour in Attendance and Displaying Reports

• Modified AttendanceRecord to hold Student and Course objects instead of just their IDs, enhancing its object-oriented nature and how records are displayed. The toDataString() method still uses IDs for simpler file storage.
• Created a displaySchoolDirectory(List<Person> people) method in Main.java to demonstrate polymorphism. This method iterates through a list of Person objects (containing Student, Teacher, Staff instances) and calls person.displayDetails(). The correct overridden method for each specific object type is executed at runtime.
• Populated a List<Person> in main and used it with displaySchoolDirectory.
• Updated Main.java to use instanceof and casting when preparing the list of students for saving, as Person itself does not implement Storable.
• Discussed how polymorphism allows for flexible and extensible code by treating different object types uniformly through a common interface or base class reference.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/*.java
3. Run: java -cp src com.school.Main

Part 8: Overloaded Commands: Multiple Ways to Mark and Query Attendance

• Created an AttendanceService.java class to encapsulate attendance logic and manage the list of AttendanceRecord objects.
• Implemented overloaded markAttendance methods in AttendanceService:
  • markAttendance(Student student, Course course, String status)
  • markAttendance(int studentId, int courseId, String status, List<Student> allStudents, List<Course> allCourses) (performs lookups)
• Implemented overloaded displayAttendanceLog methods in AttendanceService:
  • displayAttendanceLog() (shows all records)
  • displayAttendanceLog(Student student) (filters by student)
  • displayAttendanceLog(Course course) (filters by course)
• Utilized Java Streams for filtering records in the specific display methods.
• AttendanceService now uses FileStorageService to save its attendanceLog.
• Demonstrated the use of these overloaded methods in Main.java, showing how different method signatures allow for flexible ways to call the same conceptual operation.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/*.java
3. Run: java -cp src com.school.Main
4. Check attendance_log.txt for saved records.

Part 9: SOLID Service Layer: RegistrationService & AttendanceService Separation

• Applied the Single Responsibility Principle (SRP) by creating dedicated service classes.
• Created RegistrationService.java to handle the registration, management (lists, lookups), and saving of Student, Teacher, Staff, and Course entities.
• Modified Teacher.java and Staff.java to implement Storable for file persistence.
• Refactored AttendanceService.java:
  • It now depends on RegistrationService for looking up students/courses by ID.
  • Removed internal lookup helper methods, delegating this to RegistrationService.
  • Its primary focus is now solely on managing attendance records.
• Updated Main.java to act as an orchestrator, instantiating and using these services. Direct entity list management was removed from Main.
• Demonstrated improved code organization and clearer separation of concerns.

How to Run

1. Navigate to the project root directory.
2. Compile: javac src/com/school/*.java
3. Run: java -cp src com.school.Main
4. Check for students.txt, teachers.txt, staff.txt, courses.txt, and attendance_log.txt.