Create main.java

Author: KercX

src/main.java

@@ -0,0 +1,217 @@
+package com.javabooks;
+
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    private static LibraryService library = new Library();
+    private static Scanner scanner = new Scanner(System.in);
+
+    public static void main(String[] args) {
+
+        loadFromFile();
+
+        System.out.println("=== JavaBooks PRO System ===");
+
+        while (true) {
+            printMenu();
+            String input = scanner.nextLine();
+
+            switch (input) {
+                case "1": addBook(); break;
+                case "2": listBooks(); break;
+                case "3": searchMenu(); break;
+                case "4": borrowBook(); break;
+                case "5": returnBook(); break;
+                case "6": removeBook(); break;
+                case "7": sortMenu(); break;
+                case "8": statistics(); break;
+                case "9": saveToFile(); break;
+                case "10": loadFromFile(); break;
+                case "0": exit(); return;
+                default: System.out.println("Invalid option!");
+            }
+        }
+    }
+
+    private static void printMenu() {
+        System.out.println("\n===== MENU =====");
+        System.out.println("1. Add Book");
+        System.out.println("2. List Books");
+        System.out.println("3. Search");
+        System.out.println("4. Borrow Book");
+        System.out.println("5. Return Book");
+        System.out.println("6. Remove Book");
+        System.out.println("7. Sort Books");
+        System.out.println("8. Statistics");
+        System.out.println("9. Save");
+        System.out.println("10. Load");
+        System.out.println("0. Exit");
+        System.out.print("Choose: ");
+    }
+
+    private static void addBook() {
+        try {
+            System.out.print("Title: ");
+            String title = scanner.nextLine();
+
+            System.out.print("Author: ");
+            String author = scanner.nextLine();
+
+            System.out.print("Year: ");
+            int year = Integer.parseInt(scanner.nextLine());
+
+            System.out.print("ISBN: ");
+            String isbn = scanner.nextLine();
+
+            library.addBook(new Book(title, author, year, isbn));
+            System.out.println("Added!");
+        } catch (Exception e) {
+            System.out.println("Error!");
+        }
+    }
+
+    private static void listBooks() {
+        List<Book> books = library.listBooks();
+        if (books.isEmpty()) {
+            System.out.println("Empty library!");
+            return;
+        }
+
+        System.out.println("\n--- BOOKS ---");
+        for (Book b : books) {
+            System.out.println(b);
+        }
+    }
+
+    private static void searchMenu() {
+        System.out.println("1. By Title");
+        System.out.println("2. By Author");
+        String choice = scanner.nextLine();
+
+        System.out.print("Query: ");
+        String query = scanner.nextLine();
+
+        List<Book> results;
+
+        if (choice.equals("1")) {
+            results = library.searchByTitle(query);
+        } else {
+            results = library.searchByAuthor(query);
+        }
+
+        if (results.isEmpty()) {
+            System.out.println("No results.");
+        } else {
+            results.forEach(System.out::println);
+        }
+    }
+
+    private static void borrowBook() {
+        System.out.print("ISBN: ");
+        String isbn = scanner.nextLine();
+
+        Book b = library.findByIsbn(isbn);
+
+        if (b == null) {
+            System.out.println("Not found!");
+            return;
+        }
+
+        if (b.isBorrowed()) {
+            System.out.println("Already borrowed!");
+            return;
+        }
+
+        library.borrowBook(isbn);
+        System.out.println("Borrowed!");
+    }
+
+    private static void returnBook() {
+        System.out.print("ISBN: ");
+        String isbn = scanner.nextLine();
+
+        Book b = library.findByIsbn(isbn);
+
+        if (b == null) {
+            System.out.println("Not found!");
+            return;
+        }
+
+        if (!b.isBorrowed()) {
+            System.out.println("Not borrowed!");
+            return;
+        }
+
+        library.returnBook(isbn);
+        System.out.println("Returned!");
+    }
+
+    private static void removeBook() {
+        System.out.print("ISBN: ");
+        String isbn = scanner.nextLine();
+
+        library.removeBook(isbn);
+        System.out.println("Removed.");
+    }
+
+    private static void sortMenu() {
+        List<Book> books = library.listBooks();
+
+        System.out.println("1. By Title");
+        System.out.println("2. By Year");
+        String choice = scanner.nextLine();
+
+        if (choice.equals("1")) {
+            books.sort(Comparator.comparing(Book::getTitle));
+        } else {
+            books.sort(Comparator.comparingInt(Book::getYear));
+        }
+
+        books.forEach(System.out::println);
+    }
+
+    private static void statistics() {
+        List<Book> books = library.listBooks();
+
+        long total = books.size();
+        long borrowed = books.stream().filter(Book::isBorrowed).count();
+
+        System.out.println("Total books: " + total);
+        System.out.println("Borrowed: " + borrowed);
+        System.out.println("Available: " + (total - borrowed));
+    }
+
+    private static void saveToFile() {
+        try (BufferedWriter writer = new BufferedWriter(new FileWriter("books.txt"))) {
+            for (Book b : library.listBooks()) {
+                writer.write(b.getTitle() + ";" + b.getAuthor() + ";" + b.getYear() + ";" + b.getIsbn() + ";" + b.isBorrowed());
+                writer.newLine();
+            }
+            System.out.println("Saved!");
+        } catch (IOException e) {
+            System.out.println("Save error!");
+        }
+    }
+
+    private static void loadFromFile() {
+        try (BufferedReader reader = new BufferedReader(new FileReader("books.txt"))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                String[] p = line.split(";");
+                Book b = new Book(p[0], p[1], Integer.parseInt(p[2]), p[3]);
+                if (Boolean.parseBoolean(p[4])) b.borrow();
+                library.addBook(b);
+            }
+            System.out.println("Loaded!");
+        } catch (IOException e) {
+            System.out.println("No file.");
+        }
+    }
+
+    private static void exit() {
+        saveToFile();
+        System.out.println("Goodbye!");
+    }
+}