LMSMain.java

package LMS.com;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.Scanner;

public class LMSMain {

    public static void main(String[] args) {

        try (Connection connection = dbconnection.getConnection();
             Scanner sc = new Scanner(System.in)) {

            Members members = new Members();
            LibraryService services = new LibraryService();
            Transaction transactions = new Transaction();
            ReturnBook returnBook = new ReturnBook();
            // Books books = new Books();
            // IssueBook issueBook = new IssueBook();

            while (true) {

                System.out.println("\n══════════════════════════════════");
                System.out.println("📚 LIBRARY MANAGEMENT SYSTEM");
                System.out.println("══════════════════════════════════");
                System.out.println("1️⃣ Member Management");
                System.out.println("2️⃣ Library Services");
                System.out.println("3️⃣ Transactions");
                System.out.println("4️⃣ Return Book");
                System.out.println("0️⃣ Exit");
                System.out.print("👉 Select Option: ");

                int choice = sc.nextInt();

                switch (choice) {

                    case 1 -> memberMenu(members, connection, sc);
                    case 2 -> serviceMenu(services, connection, sc);
                    case 3 -> transactionMenu(transactions, connection, sc);
                    case 4 -> returnMenu(returnBook, connection, sc);

                    case 0 -> {
                        System.out.println("👋 Thank you for using LMS!");
                        return;
                    }

                    default -> System.out.println("❌ Invalid Option! Try again.");
                }
            }

        } catch (SQLException e) {
            System.out.println("⚠ Database Connection Error: " + e.getMessage());
        }
    }

    // ================= MEMBER MENU =================
    private static void memberMenu(Members members, Connection con, Scanner sc) throws SQLException {

        System.out.println("\n👥 MEMBER MANAGEMENT");
        System.out.println("1. Add Member");
        System.out.println("2. Update Member");
        System.out.println("3. Delete Member");
        System.out.println("4. View Members");
        System.out.print("Choose: ");

        int ch = sc.nextInt();

        switch (ch) {
            case 1 -> members.insert(con);
            case 2 -> members.update(con);
            case 3 -> members.delete(con);
            case 4 -> members.getAll(con);
            default -> System.out.println("❌ Invalid Choice");
        }
    }

    // ================= SERVICE MENU =================
    private static void serviceMenu(LibraryService service, Connection con, Scanner sc) throws SQLException {

        System.out.println("\n📚 LIBRARY SERVICES");
        System.out.println("1. Add Service");
        System.out.println("2. Update Service");
        System.out.println("3. Delete Service");
        System.out.println("4. View Services");
        System.out.print("Choose: ");

        int ch = sc.nextInt();

        switch (ch) {
            case 1 -> service.insert(con);
            case 2 -> service.update(con);
            case 3 -> service.delete(con);
            case 4 -> service.getAll(con);
            default -> System.out.println("❌ Invalid Choice");
        }
    }

    // ================= TRANSACTION MENU =================
    private static void transactionMenu(Transaction txn, Connection con, Scanner sc) throws SQLException {

        System.out.println("\n📑 TRANSACTIONS");
        System.out.println("1. Add Transaction");
        System.out.println("2. Update Transaction");
        System.out.println("3. Delete Transaction");
        System.out.println("4. View Transactions");
        System.out.print("Choose: ");

        int ch = sc.nextInt();

        switch (ch) {
            case 1 -> txn.insert(con);
            case 2 -> txn.update(con);
            case 3 -> txn.delete(con);
            case 4 -> txn.getAll(con);
            default -> System.out.println("❌ Invalid Choice");
        }
    }

    // ================= RETURN MENU =================
    private static void returnMenu(ReturnBook rb, Connection con, Scanner sc) throws SQLException {

        System.out.println("\n🔄 RETURN BOOK");
        System.out.println("1. Add Return");
        System.out.println("2. Update Return");
        System.out.println("3. Delete Return");
        System.out.println("4. View Returns");
        System.out.print("Choose: ");

        int ch = sc.nextInt();

        switch (ch) {
            case 1 -> rb.insert(con);
            case 2 -> rb.update(con);
            case 3 -> rb.delete(con);
            case 4 -> rb.getAll(con);
            default -> System.out.println("❌ Invalid Choice");
        }
    }
}