Entity Book, dao layer and its implementation were created and tested…

… in presentation layer

pom.xml

@@ -14,4 +14,12 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
+    <dependencies>
+        <dependency>
+            <groupId>com.mysql</groupId>
+            <artifactId>mysql-connector-j</artifactId>
+            <version>8.0.33</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 {
+    public static final Injector injector = Injector.getInstance("mate.academy");
+
     public static void main(String[] args) {
+        BookDao bookDao = (BookDao) injector.getInstance(BookDao.class);
+        Book mist = new Book();
+        mist.setTitle("Mist");
+        mist.setPrice(BigDecimal.valueOf(100));
 
+        bookDao.create(mist);
+        mist.setTitle("Mist by S.King");
+        mist.setPrice(BigDecimal.valueOf(101));
+        bookDao.update(mist);
+        System.out.println(bookDao.findById(mist.getId()));
+        bookDao.findAll().forEach(System.out::println);
+        System.out.println("delete successful: " + bookDao.deleteById(mist.getId()));
     }
 }

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

@@ -0,0 +1,17 @@
+package mate.academy.dao;
+
+import mate.academy.model.Book;
+import java.util.List;
+import java.util.Optional;
+
+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/impl/BookDaoImpl.java

@@ -0,0 +1,132 @@
+package mate.academy.dao.impl;
+
+import mate.academy.dao.BookDao;
+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.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;
+
+@Dao
+public class BookDaoImpl implements BookDao {
+    @Override
+    public Book create(Book book) {
+        String insertBookQuery = "INSERT INTO books(title, price) values(?, ?);";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement createBookStatement =
+                     connection.prepareStatement(
+                             insertBookQuery, Statement.RETURN_GENERATED_KEYS)) {
+
+            createBookStatement.setString(1, book.getTitle());
+            createBookStatement.setObject(
+                    2, book.getPrice());
+            createBookStatement.executeUpdate();
+            ResultSet generatedKeys = createBookStatement.getGeneratedKeys();
+            if (generatedKeys.next()) {
+                Long id = generatedKeys.getObject(1, Long.class);
+                book.setId(id);
+            }
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t insert book to DB" + book, e);
+        }
+        return book;
+    }
+
+    @Override
+    public Optional<Book> findById(Long id) {
+        String findByIdQuery = "SELECT * FROM books "
+                + "WHERE is_deleted = 'FALSE' AND id = ?;";
+        Book book = null;
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement findByIdStatement =
+                     connection.prepareStatement(findByIdQuery)) {
+
+            findByIdStatement.setLong(1, id);
+            ResultSet resultSet = findByIdStatement.executeQuery();
+            while (resultSet.next()) {
+                if (resultSet.getObject("id", Long.class).equals(id)) {
+                    book = getBookFromResultSet(resultSet);
+                }
+            }
+        } catch (SQLException e) {
+            throw new DataProcessingException(
+                    "Can`t find book by id from DB. id = " + id, e);
+        }
+        return Optional.ofNullable(book);
+    }
+
+    @Override
+    public List<Book> findAll() {
+        String getAllQuery = "SELECT * FROM books "
+                + "WHERE is_deleted = 'FALSE';";
+        List<Book> books = new ArrayList<>();
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement findAllBooksStatement =
+                     connection.prepareStatement(getAllQuery)) {
+            ResultSet resultSet = findAllBooksStatement.executeQuery();
+            while (resultSet.next()) {
+                Book bookFromResultSet =
+                        getBookFromResultSet(resultSet);
+                books.add(bookFromResultSet);
+            }
+        } catch (SQLException e) {
+            throw new DataProcessingException(
+                    "Can`t find all books from DB" + books, e);
+        }
+        return books;
+    }
+
+    @Override
+    public Book update(Book book) {
+        String updateQuery =
+                "UPDATE books SET title = ?, price = ? "
+                        + "WHERE is_deleted = FALSE AND id = ?;";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement updateBookStatement =
+                     connection.prepareStatement(updateQuery)) {
+
+            updateBookStatement.setString(1, book.getTitle());
+            updateBookStatement.setObject(
+                    2, book.getPrice());
+            updateBookStatement.setLong(3, book.getId());
+            updateBookStatement.executeUpdate();
+        } catch (SQLException e) {
+            throw new DataProcessingException("Can`t update book: " + book, e);
+        }
+        return book;
+    }
+
+    @Override
+    public boolean deleteById(Long id) {
+        String deleteQuery = "UPDATE books SET is_deleted = TRUE "
+                + "WHERE id = ?;";
+        try (Connection connection = ConnectionUtil.getConnection();
+             PreparedStatement deleteBookStatement =
+                     connection.prepareStatement(deleteQuery)) {
+            deleteBookStatement.setLong(1, id);
+            return deleteBookStatement.executeUpdate() > 0;
+        } catch (SQLException e) {
+            throw new DataProcessingException(
+                    "Can`t delete book by id from DB. id = " + id, e);
+        }
+    }
+
+    private Book getBookFromResultSet(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 ex) {
+        super(message, ex);
+    }
+}

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

@@ -0,0 +1,46 @@
+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 +1,33 @@
+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/books";
+    private static final String USERNAME = "root";
+    private static final String PASSWORD = "2121105";
+    private static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
+
+    static {
+        try {
+            Class.forName(JDBC_DRIVER);
+        } catch (ClassNotFoundException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static Connection getConnection() {
+        try {
+            Properties dbProperties = new Properties();
+            dbProperties.put("user", USERNAME);
+            dbProperties.put("password", PASSWORD);
+            return DriverManager.getConnection(
+                    URL, dbProperties);
+        } catch (SQLException e) {
+            throw new RuntimeException("Can`t create connection to DB", e);
+        }
+    }
+}

src/main/resources/init_db.sql

@@ -0,0 +1,9 @@
+CREATE DATABASE `books`
+
+CREATE TABLE `books`(
+    `id`         bigint NOT NULL AUTO_INCREMENT,
+    `title`      varchar(45) DEFAULT NULL,
+    `price`      bigint      DEFAULT NULL,
+    `is_deleted` tinyint(1) DEFAULT NULL,
+    PRIMARY KEY (`id`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3;