JAVA PROJECT PRESENTATION

package com.payilagam.entity; public class Book { private int id; private String name; private String author; private int quantity; public Book() { } public Book(String name, String author, int quantity) { this.name = name; this.author = author; this.quantity = quantity; } public Book(int id, String name, String author, int quantity) { this.id = id; this.name = name; this.author = author; this.quantity = quantity; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getAuthor() { return author; } public void setAuthor(String author) { this.author = author; } public int getQuantity() { return quantity; } public void setQuantity(int quantity) { this.quantity = quantity; } public String toString() { return "Book ID: " + id + ", Name: " + name + ", Author: " + author + ", Quantity: " + quantity; } } 

package com.payilagam.service; import com.payilagam.db.DatabaseConnection; import com.payilagam.entity.Book; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; public class BookService { public void addBook(Book book) throws SQLException { String sql = "INSERT INTO books (name, author, quantity) VALUES (?, ?, ?)"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql)) { ps.setString(1, book.getName()); ps.setString(2, book.getAuthor()); ps.setInt(3, book.getQuantity()); ps.executeUpdate(); } } public List<Book> getAllBooks() throws SQLException { List<Book> books = new ArrayList<>(); String sql = "SELECT * FROM books ORDER BY id"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql); ResultSet rs = ps.executeQuery()) { while (rs.next()) { Book book = new Book( rs.getInt("id"), rs.getString("name"), rs.getString("author"), rs.getInt("quantity") ); books.add(book); } } return books; } public Book findById(int id) throws SQLException { String sql = "SELECT * FROM books WHERE id = ?"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql)) { ps.setInt(1, id); try (ResultSet rs = ps.executeQuery()) { if (rs.next()) { return new Book( rs.getInt("id"), rs.getString("name"), rs.getString("author"), rs.getInt("quantity") ); } } } return null; } public List<Book> findByName(String name) throws SQLException { List<Book> books = new ArrayList<>(); String sql = "SELECT * FROM books WHERE name ILIKE ? ORDER BY id"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql)) { ps.setString(1, "%" + name + "%"); try (ResultSet rs = ps.executeQuery()) { while (rs.next()) { books.add(new Book( rs.getInt("id"), rs.getString("name"), rs.getString("author"), rs.getInt("quantity") )); } } } return books; } public List<Book> findByAuthor(String author) throws SQLException { List<Book> books = new ArrayList<>(); String sql = "SELECT * FROM books WHERE author ILIKE ? ORDER BY id"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql)) { ps.setString(1, "%" + author + "%"); try (ResultSet rs = ps.executeQuery()) { while (rs.next()) { books.add(new Book( rs.getInt("id"), rs.getString("name"), rs.getString("author"), rs.getInt("quantity") )); } } } return books; } public void updateBook(Book book) throws SQLException { String sql = "UPDATE books SET name = ?, author = ?, quantity = ? WHERE id = ?"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql)) { ps.setString(1, book.getName()); ps.setString(2, book.getAuthor()); ps.setInt(3, book.getQuantity()); ps.setInt(4, book.getId()); ps.executeUpdate(); } } public void deleteBook(int id) throws SQLException { String sql = "DELETE FROM books WHERE id = ?"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql)) { ps.setInt(1, id); ps.executeUpdate(); } } public int getBookCount() throws SQLException { String sql = "SELECT COUNT(*) FROM books"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql); ResultSet rs = ps.executeQuery()) { if (rs.next()) { return rs.getInt(1); } } return 0; } public int getMaxQuantity() throws SQLException { String sql = "SELECT MAX(quantity) FROM books"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql); ResultSet rs = ps.executeQuery()) { if (rs.next()) { return rs.getInt(1); } } return 0; } public int getMinQuantity() throws SQLException { String sql = "SELECT MIN(quantity) FROM books"; try (Connection con = DatabaseConnection.getConnection(); PreparedStatement ps = con.prepareStatement(sql); ResultSet rs = ps.executeQuery()) { if (rs.next()) { return rs.getInt(1); } } return 0; } } 

package com.payilagam.controller; import com.payilagam.entity.Book; import com.payilagam.service.BookService; import java.sql.SQLException; import java.util.List; public class Controller { public static void main(String[] args) { BookService service = new BookService(); try { /*Book newBook = new Book("Java Basics","James Gosling",10); service.addBook(newBook); System.out.println("Book added successfully");*/ System.out.println("\nAll Books:"); List<Book> books = service.getAllBooks(); for (Book book : books) { System.out.println(book); } System.out.println("\nSearch by Book ID:"); Book book = service.findById(1); if (book != null) { System.out.println(book); } else { System.out.println("Book not found"); } System.out.println("\nSearch by Book Name:"); List<Book> bookNames = service.findByName("Java"); for (Book b : bookNames) { System.out.println(b); } System.out.println("\nSearch by Author:"); List<Book> authors = service.findByAuthor("James"); for (Book b : authors) { System.out.println(b); } System.out.println("\nUpdate Book:"); Book updateBook = service.findById(1); if (updateBook != null) { updateBook.setName("Java Programming"); updateBook.setAuthor("James Gosling"); updateBook.setQuantity(20); service.updateBook(updateBook); System.out.println("Book updated successfully"); } else { System.out.println("Book not found for update"); } service.deleteBook(2); System.out.println("Book deleted successfully"); System.out.println("\nTotal Books: " + service.getBookCount()); System.out.println("Maximum Quantity: " + service.getMaxQuantity()); System.out.println("Minimum Quantity: " + service.getMinQuantity()); } catch (SQLException exp) { System.out.println("Database error: " + exp.getMessage()); } } } 

package com.payilagam.db; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; public class DatabaseConnection { private static final String URL = "jdbc:postgresql://localhost:5432/library"; private static final String USERNAME = "postgres"; // Replace this with your actual PostgreSQL password. private static final String PASSWORD = "20223465"; public static Connection getConnection() throws SQLException { return DriverManager.getConnection( URL, USERNAME, PASSWORD ); } }