Added solution to the task:

- established connection to db
- created init_db.sql file in src/main/resources folder
- created layer for Book model
- used injector and Dao annotation
- called all CRUD methods in Main class

pom.xml

@@ -14,4 +14,12 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
+    <dependencies>
+        <dependency>
+            <groupId>mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+            <version>8.0.24</version>
+        </dependency>
+    </dependencies>
+
 </project>

src/main/java/mate/academy/Main.java

@@ -1,7 +1,25 @@
 package mate.academy;
 
+import mate.academy.dao.BookDao;
+import mate.academy.lib.Injector;
+import mate.academy.model.Book;
+import java.math.BigDecimal;
+
 public class Main {
+    private static final Injector injector = Injector.getInstance("mate.academy");
+
     public static void main(String[] args) {
+        Book theTimeBook = new Book();
+        theTimeBook.setId(1L);
+        theTimeBook.setTitle("The time");
+        theTimeBook.setPrice(BigDecimal.valueOf(80));
+        Book myWarBook = new Book(3L, "My war", BigDecimal.valueOf(130));
 
+        BookDao bookDao = (BookDao) injector.getInstance(BookDao.class);
+        System.out.println(bookDao.create(myWarBook));
+        System.out.println(bookDao.findById(1L).get());
+        System.out.println(bookDao.findAll());
+        System.out.println(bookDao.update(theTimeBook));
+        System.out.println(bookDao.deleteById(2L));
     }
 }

src/main/java/mate/academy/dao/BookDao.java

@@ -0,0 +1,17 @@
+package mate.academy.dao;
+
+import java.util.List;
+import java.util.Optional;
+import mate.academy.model.Book;
+
+public interface BookDao {
+    Book create(Book book);
+
+    Optional<Book> findById(Long id);
+
+    List<Book> findAll();
+
+    Book update(Book book);
+
+    boolean deleteById(Long id);
+}

src/main/java/mate/academy/dao/BookDaoImpl.java

@@ -0,0 +1,114 @@
+package mate.academy.dao;
+
+import mate.academy.exception.DataProcessingException;
+import mate.academy.lib.Dao;
+import mate.academy.model.Book;
+import mate.academy.util.ConnectionUtil;
+import java.math.BigDecimal;
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+@Dao
+public class BookDaoImpl implements BookDao {
+    @Override
+    public Book create(Book book) {
+        String query = "INSERT INTO books (title, price) VALUES(?, ?)";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement statement = connection.prepareStatement(query,
+                     Statement.RETURN_GENERATED_KEYS)) {
+            statement.setString(1, book.getTitle());
+            statement.setBigDecimal(2, book.getPrice());
+
+            int affectedRows = statement.executeUpdate();
+            if (affectedRows < 1) {
+                throw new RuntimeException("Expected to insert at"
+                        + " least one row, but inserted 0 rows");
+            }
+
+            ResultSet generatedKeys = statement.getGeneratedKeys();
+            if (generatedKeys.next()) {
+                Long id = generatedKeys.getObject(1, Long.class);
+                book.setId(id);
+            }
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can't insert book " + book + "to DB", e);
+        }
+        return book;
+    }
+
+    @Override
+    public Optional<Book> findById(Long id) {
+        String query = "SELECT * FROM books WHERE id = ? AND is_deleted = FALSE";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement statement = connection.prepareStatement(query)) {
+            statement.setLong(1, id);
+            ResultSet resultSet = statement.executeQuery();
+
+            Book book = new Book();
+            if (resultSet.next()) {
+                String title = resultSet.getString("title");
+                BigDecimal price = resultSet.getBigDecimal("price");
+
+                book.setId(id);
+                book.setTitle(title);
+                book.setPrice(price);
+            }
+            return Optional.ofNullable(book);
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can't get book by id " + id, e);
+        }
+    }
+
+    @Override
+    public List<Book> findAll() {
+        String query = "SELECT * FROM books WHERE is_deleted = FALSE";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement statement = connection.prepareStatement(query)) {
+            List<Book> books = new ArrayList<>();
+            ResultSet resultSet = statement.executeQuery();
+            while (resultSet.next()) {
+                books.add(getBook(resultSet));
+            }
+            return books;
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can't find any book", e);
+        }
+    }
+
+    @Override
+    public Book update(Book book) {
+        String query = "UPDATE books SET title = ?, price = ? " +
+                "WHERE id = ? AND is_deleted = FALSE";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement statement = connection.prepareStatement(query)) {
+            statement.setString(1, book.getTitle());
+            statement.setBigDecimal(2, book.getPrice());
+            statement.setLong(3, book.getId());
+            statement.executeUpdate();
+            return book;
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can't update book " + book, e);
+        }
+    }
+
+    @Override
+    public boolean deleteById(Long id) {
+        String query = "UPDATE books SET is_deleted = TRUE WHERE id = ?";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement statement = connection.prepareStatement(query)) {
+            statement.setLong(1, id);
+            return statement.executeUpdate() > 0;
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can't delete book with id " + id, e);
+        }
+    }
+
+    private Book getBook(ResultSet resultSet) throws SQLException {
+        Long id = resultSet.getObject("id", Long.class);
+        String title = resultSet.getString("title");
+        BigDecimal price = resultSet.getBigDecimal("price");
+        return new Book(id, title, price);
+    }
+}

src/main/java/mate/academy/exception/DataProcessingException.java

@@ -0,0 +1,7 @@
+package mate.academy.exception;
+
+public class DataProcessingException extends RuntimeException {
+    public DataProcessingException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/mate/academy/model/Book.java

@@ -0,0 +1,56 @@
+package mate.academy.model;
+
+import java.math.BigDecimal;
+
+public class Book {
+    private Long id;
+    private String title;
+    private BigDecimal price;
+
+    public Long getId() {
+        return id;
+    }
+
+    public Book() {
+    }
+
+    public Book(String title, BigDecimal price) {
+        this.title = title;
+        this.price = price;
+    }
+
+    public Book(Long id, String title, BigDecimal price) {
+        this.id = id;
+        this.title = title;
+        this.price = price;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public BigDecimal getPrice() {
+        return price;
+    }
+
+    public void setPrice(BigDecimal price) {
+        this.price = price;
+    }
+
+    @Override
+    public String toString() {
+        return "Book{"
+                + "id=" + id
+                + ", title='" + title + '\''
+                + ", price=" + price
+                + '}';
+    }
+}

src/main/java/mate/academy/util/ConnectionUtil.java

@@ -0,0 +1,28 @@
+package mate.academy.util;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.util.Properties;
+
+public class ConnectionUtil {
+    private static final String URL = "jdbc:mysql://localhost:3306/book_db";
+    private static final String USERNAME = "root";
+    private static final String PASSWORD = "123456789";
+    private static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
+
+    static {
+        try {
+            Class.forName(JDBC_DRIVER);
+        } catch (ClassNotFoundException e) {
+            throw new RuntimeException("Can't find SQL Driver", e);
+        }
+    }
+
+    public static Connection getConnection() throws SQLException {
+        Properties dbProperties = new Properties();
+        dbProperties.setProperty("user", USERNAME);
+        dbProperties.setProperty("password", PASSWORD);
+        return DriverManager.getConnection(URL, dbProperties);
+    }
+}

src/main/resources/init_db.sql

@@ -0,0 +1,10 @@
+CREATE SCHEMA IF NOT EXISTS `book_db` DEFAULT CHARACTER SET utf8;
+USE `book_db`;
+
+CREATE TABLE `books` (
+                         `id` int NOT NULL AUTO_INCREMENT,
+                         `title` varchar(200) DEFAULT NULL,
+                         `price` decimal(10,0) DEFAULT NULL,
+                         `is_deleted` tinyint DEFAULT '0',
+                         PRIMARY KEY (`id`)
+) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb3;