established connection to DB, created Book entity class and BookDao i…

pom.xml

@@ -18,6 +18,15 @@
         </maven.checkstyle.plugin.configLocation>
     </properties>
 
+    <dependencies>
+        <dependency>
+            <groupId>mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+            <version>8.0.33</version>
+        </dependency>
+
+    </dependencies>
+
     <build>
         <plugins>
             <plugin>

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

@@ -1,7 +1,30 @@
 package mate.academy;
 
+import java.math.BigDecimal;
+import java.util.Optional;
+import mate.academy.dao.BookDao;
+import mate.academy.lib.Injector;
+import mate.academy.model.Book;
+
 public class Main {
+    private static final Injector injector = Injector.getInstance("mate.academy");
+
     public static void main(String[] args) {
+        BookDao bookDao = (BookDao) injector.getInstance(BookDao.class);
+
+        Book book = new Book();
+        book.setTitle("Sherlock Holmes");
+        book.setPrice(BigDecimal.valueOf(110L));
+
+        Book savedBook = bookDao.create(book);
+        Optional<Book> bookById = bookDao.findById(savedBook.getId());
+        System.out.println(bookById);
+        System.out.println(bookDao.findAll());
 
+        book.setPrice(BigDecimal.valueOf(371L));
+        bookDao.update(book);
+        bookDao.findById(savedBook.getId());
+        bookDao.deleteById(savedBook.getId());
+        System.out.println(bookDao.findAll());
     }
 }

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 +1,129 @@
+package mate.academy.dao;
+
+import java.math.BigDecimal;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import mate.academy.exception.DataProcessingException;
+import mate.academy.lib.Dao;
+import mate.academy.model.Book;
+import mate.academy.util.ConnectionUtil;
+
+@Dao
+public class BookDaoImpl implements BookDao {
+
+    @Override
+    public Book create(Book book) {
+        String insertRequest = "INSERT INTO books (title, price) VALUES (?, ?)";
+        try (Connection connection = ConnectionUtil.getConnection();
+                PreparedStatement createObjectStatement
+                        = connection.prepareStatement(insertRequest,
+                        Statement.RETURN_GENERATED_KEYS)) {
+            createObjectStatement.setString(1, book.getTitle());
+            createObjectStatement.setBigDecimal(2, book.getPrice());
+
+            int affectedRows = createObjectStatement.executeUpdate();
+            if (affectedRows < 1) {
+                throw new RuntimeException("Expected to insert at least 1 row, "
+                        + "but inserted 0 rows");
+            }
+
+            ResultSet generatedKeys = createObjectStatement.getGeneratedKeys();
+            if (generatedKeys.next()) {
+                book.setId(generatedKeys.getLong(1));
+            }
+
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t insert book "
+                    + book + " to DB", e);
+        }
+        return book;
+    }
+
+    @Override
+    public Optional<Book> findById(Long id) {
+        String getRequest = "SELECT * FROM books WHERE id = ?";
+        try (Connection connection = ConnectionUtil.getConnection();
+                PreparedStatement getBookStatement
+                        = connection.prepareStatement(getRequest)) {
+            getBookStatement.setLong(1, id);
+            ResultSet resultSet = getBookStatement.executeQuery();
+
+            if (resultSet.next()) {
+                Book book = createBook(resultSet);
+                return Optional.of(book);
+            }
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t get book by id = " + id, e);
+        }
+        return Optional.empty();
+    }
+
+    @Override
+    public List<Book> findAll() {
+        List<Book> books = new ArrayList<>();
+        String getAllRequest = "SELECT * FROM books";
+        try (Connection connection = ConnectionUtil.getConnection();
+                PreparedStatement getAllBooksStatement
+                        = connection.prepareStatement(getAllRequest)) {
+            ResultSet resultSet = getAllBooksStatement.executeQuery();
+
+            while (resultSet.next()) {
+                Book book = createBook(resultSet);
+                books.add(book);
+            }
+
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t get all books from DB", e);
+        }
+        return books;
+    }
+
+    @Override
+    public Book update(Book book) {
+        String updateRequest = "UPDATE books SET title = ?, price = ? WHERE id = ?";
+        try (Connection connection = ConnectionUtil.getConnection();
+                PreparedStatement updateBookStatement
+                        = connection.prepareStatement(updateRequest)) {
+            updateBookStatement.setString(1, book.getTitle());
+            updateBookStatement.setBigDecimal(2, book.getPrice());
+            updateBookStatement.setString(3, String.valueOf(book.getId()));
+            updateBookStatement.executeUpdate();
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t update book "
+                    + book + " from DB", e);
+        }
+        return book;
+    }
+
+    @Override
+    public boolean deleteById(Long id) {
+        String deleteRequest = "DELETE FROM books WHERE id = ?";
+        try (Connection connection = ConnectionUtil.getConnection();
+                PreparedStatement deletedStatement
+                        = connection.prepareStatement(deleteRequest)) {
+            deletedStatement.setLong(1, id);
+            int rowsAffected = deletedStatement.executeUpdate();
+            return rowsAffected > 0;
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t delete book by id "
+                    + id + " from DB", e);
+        }
+    }
+
+    private static Book createBook(ResultSet resultSet) throws SQLException {
+        Long id = resultSet.getObject("id", Long.class);
+        String title = resultSet.getString("title");
+        BigDecimal price = resultSet.getObject("price", BigDecimal.class);
+        Book book = new Book();
+        book.setId(id);
+        book.setTitle(title);
+        book.setPrice(price);
+        return book;
+    }
+}

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 +1,42 @@
+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 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 DB_URL = "jdbc:mysql://localhost:3306/test";
+
+    private static final Properties DB_PROPERTIES;
+
+    static {
+        DB_PROPERTIES = new Properties();
+        DB_PROPERTIES.put("user", "root");
+        DB_PROPERTIES.put("password", "202-42HP");
+
+        try {
+            Class.forName("com.mysql.cj.jdbc.Driver");
+        } catch (ClassNotFoundException e) {
+            throw new RuntimeException("Can not load JDBC driver for MySQL", e);
+        }
+    }
+
+    public static Connection getConnection() throws SQLException {
+        return DriverManager.getConnection(DB_URL, DB_PROPERTIES);
+    }
+}

src/main/java/resources/init_db.sql

@@ -0,0 +1,7 @@
+CREATE DATABASE test;
+CREATE TABLE books (
+                       id BIGINT NOT NULL AUTO_INCREMENT,
+                       title VARCHAR(255),
+                       price DECIMAL(10,2),
+                       PRIMARY KEY (id)
+);