Added Advanced Features such as Reservation System for unavailable books, Multi-Branch Support, Book Transfer,Recommendation System,Notification System

solutions/java/src/librarymanagementsystem/.gitignore

@@ -0,0 +1,25 @@
+# Java compiled bytecode files
+*.class
+
+# IDE files
+.idea/
+*.iml
+.vscode/
+*.swp
+*.swo
+
+# OS generated files
+.DS_Store
+Thumbs.db
+
+# Build directories
+target/
+build/
+out/
+
+# Log files
+*.log
+
+# Temporary files
+*.tmp
+*.temp

solutions/java/src/librarymanagementsystem/LibraryDemo.java

@@ -0,0 +1,351 @@
+package librarymanagementsystem;
+
+import librarymanagementsystem.models.*;
+import librarymanagementsystem.services.*;
+import librarymanagementsystem.repositories.*;
+import librarymanagementsystem.utils.IdGenerator;
+import librarymanagementsystem.patterns.factory.LibraryItemFactory;
+
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Demo class to showcase Library Management System functionality.
+ * Demonstrates all features including:
+ * - Book Management
+ * - Patron Management
+ * - Lending Process
+ * - Reservation System
+ * - Multi-branch Support
+ * - Recommendation System
+ * - Design Patterns (Observer, Factory, Strategy)
+ */
+public class LibraryDemo {
+
+    public static void main(String[] args) {
+        System.out.println("=".repeat(60));
+        System.out.println("📚 LIBRARY MANAGEMENT SYSTEM DEMO");
+        System.out.println("=".repeat(60));
+        System.out.println();
+
+        // Initialize system
+        LibraryManagementSystem library = initializeSystem();
+
+        // Demo scenarios
+        demoBookManagement(library);
+        demoPatronManagement(library);
+        demoLendingProcess(library);
+        demoReservationSystem(library);
+        demoMultiBranchSupport(library);
+        demoRecommendationSystem(library);
+        demoDesignPatterns();
+
+        System.out.println("\n" + "=".repeat(60));
+        System.out.println("✅ DEMO COMPLETED SUCCESSFULLY");
+        System.out.println("=".repeat(60));
+    }
+
+    /**
+     * Initialize the library system with dependencies (DIP).
+     */
+    private static LibraryManagementSystem initializeSystem() {
+        System.out.println("🔧 Initializing Library Management System...\n");
+
+        // Create repositories
+        BookRepository bookRepo = new BookRepository();
+        PatronRepository patronRepo = new PatronRepository();
+        LoanRepository loanRepo = new LoanRepository();
+
+        // Create services
+        NotificationService notificationService = new NotificationService();
+        BookService bookService = new BookService(bookRepo);
+        PatronService patronService = new PatronService(patronRepo);
+        LoanService loanService = new LoanService(bookRepo, patronRepo, loanRepo, notificationService);
+        ReservationService reservationService = new ReservationService(bookRepo, patronRepo, notificationService);
+        BranchService branchService = new BranchService(bookRepo);
+        RecommendationService recommendationService = new RecommendationService(bookRepo, loanRepo);
+
+        // Create main system
+        return new LibraryManagementSystem(
+            bookService,
+            patronService,
+            loanService,
+            reservationService,
+            branchService,
+            recommendationService
+        );
+    }
+
+    /**
+     * Demo 1: Book Management (Add, Update, Search, Remove).
+     */
+    private static void demoBookManagement(LibraryManagementSystem library) {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("📖 DEMO 1: BOOK MANAGEMENT");
+        System.out.println("-".repeat(60));
+
+        // Create branches first
+        Branch mainBranch = new Branch("BR001", "Main Library", "123 Main St");
+        library.addBranch(mainBranch);
+
+        // Add books
+        Book book1 = new Book("978-0132350884", "Clean Code", "Robert C. Martin", 2008);
+        Book book2 = new Book("978-0201633610", "Design Patterns", "Gang of Four", 1994);
+        Book book3 = new Book("978-0134685991", "Effective Java", "Joshua Bloch", 2017);
+        Book book4 = new Book("978-0596007126", "Head First Design Patterns", "Eric Freeman", 2004);
+
+        library.addBook(book1, "BR001");
+        library.addBook(book2, "BR001");
+        library.addBook(book3, "BR001");
+        library.addBook(book4, "BR001");
+
+        System.out.println("\n📚 Total books in library: " + library.getAllBooks().size());
+
+        // Search books
+        System.out.println("\n🔍 Searching for 'Design':");
+        List<Book> searchResults = library.searchBooks("Design");
+        searchResults.forEach(book -> System.out.println("   - " + book.getTitle() + " by " + book.getAuthor()));
+
+        // Update book
+        book1.setTitle("Clean Code: A Handbook of Agile Software Craftsmanship");
+        library.updateBook(book1);
+
+        System.out.println("\n✅ Book Management Demo Completed");
+    }
+
+    /**
+     * Demo 2: Patron Management (Register, Update, Search).
+     */
+    private static void demoPatronManagement(LibraryManagementSystem library) {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("👥 DEMO 2: PATRON MANAGEMENT");
+        System.out.println("-".repeat(60));
+
+        // Register patrons
+        Patron patron1 = new Patron("P001", "Alice Johnson", "[email protected]", Patron.PatronType.REGULAR);
+        Patron patron2 = new Patron("P002", "Bob Smith", "[email protected]", Patron.PatronType.PREMIUM);
+        Patron patron3 = new Patron("P003", "Charlie Brown", "[email protected]", Patron.PatronType.STUDENT);
+
+        library.registerPatron(patron1);
+        library.registerPatron(patron2);
+        library.registerPatron(patron3);
+
+        System.out.println("\n👥 Total patrons: " + library.getAllPatrons().size());
+
+        // Display patron info
+        System.out.println("\n📋 Patron Details:");
+        library.getAllPatrons().forEach(patron -> 
+            System.out.println("   - " + patron.getName() + " (" + patron.getPatronType() + 
+                             ") - Max books: " + patron.getMaxBooksAllowed())
+        );
+
+        // Update patron
+        patron1.setPatronType(Patron.PatronType.PREMIUM);
+        library.updatePatron(patron1);
+        System.out.println("\n✅ " + patron1.getName() + " upgraded to PREMIUM");
+
+        System.out.println("\n✅ Patron Management Demo Completed");
+    }
+
+    /**
+     * Demo 3: Lending Process (Checkout, Return, Late Fees).
+     */
+    private static void demoLendingProcess(LibraryManagementSystem library) {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("📤 DEMO 3: LENDING PROCESS");
+        System.out.println("-".repeat(60));
+
+        // Checkout books
+        System.out.println("\n📤 Checking out books...");
+        LoanRecord loan1 = library.checkoutBook("978-0132350884", "P001");
+        LoanRecord loan2 = library.checkoutBook("978-0201633610", "P002");
+        LoanRecord loan3 = library.checkoutBook("978-0134685991", "P001");
+
+        System.out.println("\n📊 Active Loans: " + library.getActiveLoans().size());
+
+        // Display loan details
+        System.out.println("\n📋 Loan Details:");
+        library.getActiveLoans().forEach(loan -> 
+            System.out.println("   - " + loan.getBook().getTitle() + 
+                             " borrowed by " + loan.getPatron().getName() + 
+                             " (Due: " + loan.getDueDate() + ")")
+        );
+
+        // Return a book
+        System.out.println("\n📥 Returning book...");
+        library.returnBook("978-0132350884", "P001");
+
+        System.out.println("\n📊 Active Loans after return: " + library.getActiveLoans().size());
+
+        // Check patron history
+        System.out.println("\n📜 Patron P001 Borrowing History:");
+        List<LoanRecord> history = library.getPatronHistory("P001");
+        history.forEach(loan -> 
+            System.out.println("   - " + loan.getBook().getTitle() + 
+                             " (Status: " + loan.getStatus() + ")")
+        );
+
+        System.out.println("\n✅ Lending Process Demo Completed");
+    }
+
+    /**
+     * Demo 4: Reservation System (Reserve, Notify, Cancel).
+     */
+    private static void demoReservationSystem(LibraryManagementSystem library) {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("🔖 DEMO 4: RESERVATION SYSTEM");
+        System.out.println("-".repeat(60));
+
+        // Try to reserve a checked-out book
+        System.out.println("\n🔖 Reserving checked-out book...");
+        try {
+            Reservation reservation1 = library.reserveBook("978-0201633610", "P003");
+            System.out.println("✅ Reservation created: " + reservation1.getReservationId());
+
+            // Check queue position
+            int position = library.getQueuePosition("978-0201633610", "P003");
+            System.out.println("📍 Queue position: " + position);
+
+            // Another patron reserves the same book
+            Reservation reservation2 = library.reserveBook("978-0201633610", "P001");
+            int position2 = library.getQueuePosition("978-0201633610", "P001");
+            System.out.println("📍 Second patron queue position: " + position2);
+
+        } catch (Exception e) {
+            System.out.println("❌ Reservation failed: " + e.getMessage());
+        }
+
+        // Return the book and trigger notification
+        System.out.println("\n📥 Returning reserved book (triggers notification)...");
+        library.returnBook("978-0201633610", "P002");
+
+        System.out.println("\n✅ Reservation System Demo Completed");
+    }
+
+    /**
+     * Demo 5: Multi-Branch Support (Add Branch, Transfer Books).
+     */
+    private static void demoMultiBranchSupport(LibraryManagementSystem library) {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("🏢 DEMO 5: MULTI-BRANCH SUPPORT");
+        System.out.println("-".repeat(60));
+
+        // Add new branch
+        Branch branch2 = new Branch("BR002", "Downtown Library", "456 Downtown Ave");
+        library.addBranch(branch2);
+
+        System.out.println("\n🏢 Total branches: " + library.getAllBranches().size());
+
+        // Display branches
+        System.out.println("\n📋 Branch List:");
+        library.getAllBranches().forEach(branch -> 
+            System.out.println("   - " + branch.getBranchName() + " (" + branch.getBranchId() + ")")
+        );
+
+        // Add book to new branch
+        Book book5 = new Book("978-0321125217", "Domain-Driven Design", "Eric Evans", 2003);
+        library.addBook(book5, "BR002");
+
+        // ✅ FIX: Return the book before transferring
+        System.out.println("\n📥 Returning book before transfer...");
+        try {
+            library.returnBook("978-0134685991", "P001");
+        } catch (Exception e) {
+            System.out.println("⚠️ Book already returned or not checked out");
+        }
+
+        // Transfer book between branches
+        System.out.println("\n🔄 Transferring book between branches...");
+        try {
+            // library.transferBook("978-0134685991", "BR001", "BR002");
+            library.transferBook("978-0596007126", "BR001", "BR002");
+        } catch (Exception e) {
+            System.out.println("❌ Transfer failed: " + e.getMessage());
+        }
+
+        // Check branch inventories
+        System.out.println("\n📚 Main Library Inventory: " + 
+                        library.getBranchInventory("BR001").size() + " books");
+        System.out.println("📚 Downtown Library Inventory: " + 
+                        library.getBranchInventory("BR002").size() + " books");
+
+        // Search across branches
+        System.out.println("\n🔍 Searching 'Design' across all branches:");
+        Map<String, List<Book>> results = library.searchBookAcrossBranches("Design");
+        results.forEach((branchName, books) -> {
+            System.out.println("   " + branchName + ":");
+            books.forEach(book -> System.out.println("      - " + book.getTitle()));
+        });
+
+        System.out.println("\n✅ Multi-Branch Support Demo Completed");
+    }
+    /**
+     * Demo 6: Recommendation System.
+     */
+    private static void demoRecommendationSystem(LibraryManagementSystem library) {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("💡 DEMO 6: RECOMMENDATION SYSTEM");
+        System.out.println("-".repeat(60));
+
+        // Get recommendations for patron based on history
+        System.out.println("\n💡 Personalized recommendations for Alice (P001):");
+        List<Book> recommendations = library.getRecommendations("P001", 3);
+        if (recommendations.isEmpty()) {
+            System.out.println("   No recommendations available yet");
+        } else {
+            recommendations.forEach(book -> 
+                System.out.println("   - " + book.getTitle() + " by " + book.getAuthor())
+            );
+        }
+
+        // Get popular books
+        System.out.println("\n🔥 Most Popular Books:");
+        List<Book> popularBooks = library.getPopularBooks(3);
+        popularBooks.forEach(book -> 
+            System.out.println("   - " + book.getTitle() + " by " + book.getAuthor())
+        );
+
+        // Get similar books
+        System.out.println("\n📚 Books similar to 'Clean Code':");
+        List<Book> similarBooks = library.getSimilarBooks("978-0132350884", 2);
+        if (similarBooks.isEmpty()) {
+            System.out.println("   No similar books found");
+        } else {
+            similarBooks.forEach(book -> 
+                System.out.println("   - " + book.getTitle() + " by " + book.getAuthor())
+            );
+        }
+
+        System.out.println("\n✅ Recommendation System Demo Completed");
+    }
+
+    /**
+     * Demo 7: Design Patterns Showcase.
+     */
+    private static void demoDesignPatterns() {
+        System.out.println("\n" + "-".repeat(60));
+        System.out.println("🎨 DEMO 7: DESIGN PATTERNS SHOWCASE");
+        System.out.println("-".repeat(60));
+
+        // Factory Pattern
+        System.out.println("\n🏭 Factory Pattern:");
+        System.out.println("   Creating library items using Factory...");
+        var bookItem = LibraryItemFactory.createBook("978-1234567890", "Test Book", "Test Author", 2024);
+        var magazineItem = LibraryItemFactory.createMagazine("MAG-2024-01", "Tech Monthly");
+        System.out.println("   ✅ Created: " + bookItem.getItemType() + " - " + bookItem.getTitle());
+        System.out.println("   ✅ Created: " + magazineItem.getItemType() + " - " + magazineItem.getTitle());
+
+        // Strategy Pattern
+        System.out.println("\n📊 Strategy Pattern:");
+        System.out.println("   Calculating late fees using different strategies...");
+        System.out.println("   Book (10 days late): $" + bookItem.calculateLateFee(10));
+        System.out.println("   Magazine (10 days late): $" + magazineItem.calculateLateFee(10));
+
+        // Observer Pattern
+        System.out.println("\n👁️ Observer Pattern:");
+        System.out.println("   Demonstrated in Reservation System");
+        System.out.println("   Patrons are notified when reserved books become available");
+
+        System.out.println("\n✅ Design Patterns Demo Completed");
+    }
+}