From 8080f29eb6e14e344726802800d9df78eb77a22c Mon Sep 17 00:00:00 2001 From: Mikhailo <88093373+MukhailoVorobets@users.noreply.github.com> Date: Sun, 21 Jul 2024 19:24:29 +0300 Subject: [PATCH] JDBC intro. --- src/main/java/mate/academy/Main.java | 21 ++++ src/main/java/mate/academy/dao/BookDao.java | 18 +++ .../java/mate/academy/dao/BookDaoImpl.java | 116 ++++++++++++++++++ .../exception/DataProcessingException.java | 11 ++ src/main/java/mate/academy/lib/Dao.java | 3 + src/main/java/mate/academy/model/Book.java | 42 +++++++ .../mate/academy/util/ConnectionUtil.java | 26 ++++ src/main/resources/init_db.sql | 7 ++ 8 files changed, 244 insertions(+) create mode 100644 src/main/java/mate/academy/dao/BookDao.java create mode 100644 src/main/java/mate/academy/dao/BookDaoImpl.java create mode 100644 src/main/java/mate/academy/exception/DataProcessingException.java create mode 100644 src/main/java/mate/academy/model/Book.java create mode 100644 src/main/java/mate/academy/util/ConnectionUtil.java create mode 100644 src/main/resources/init_db.sql diff --git a/src/main/java/mate/academy/Main.java b/src/main/java/mate/academy/Main.java index 0058fbf9..f6ef5c9b 100644 --- a/src/main/java/mate/academy/Main.java +++ b/src/main/java/mate/academy/Main.java @@ -1,7 +1,28 @@ package mate.academy; +import java.math.BigDecimal; +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("BookTitle_1"); + book.setPrice(BigDecimal.valueOf(100.00)); + + bookDao.create(book); + bookDao.findById(book.getId()).ifPresent(System.out::println); + + book.setTitle("BookTitle_test"); + book.setPrice(BigDecimal.valueOf(200.00)); + bookDao.update(book); + bookDao.findAll().stream().forEach(System.out::println); + + System.out.println(bookDao.deleteById(book.getId())); } } diff --git a/src/main/java/mate/academy/dao/BookDao.java b/src/main/java/mate/academy/dao/BookDao.java new file mode 100644 index 00000000..9fc4cce4 --- /dev/null +++ b/src/main/java/mate/academy/dao/BookDao.java @@ -0,0 +1,18 @@ +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 findById(Long id); + + List findAll(); + + Book update(Book book); + + boolean deleteById(Long id); +} diff --git a/src/main/java/mate/academy/dao/BookDaoImpl.java b/src/main/java/mate/academy/dao/BookDaoImpl.java new file mode 100644 index 00000000..15b40842 --- /dev/null +++ b/src/main/java/mate/academy/dao/BookDaoImpl.java @@ -0,0 +1,116 @@ +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 sql = "INSERT INTO books (title, price) VALUES(?, ?)"; + try (Connection connection = ConnectionUtil.getConnection(); + PreparedStatement statement = + connection.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS)) { + statement.setString(1,book.getTitle()); + statement.setBigDecimal(2,book.getPrice()); + int affectedRows = statement.executeUpdate(); + + if (affectedRows < 1) { + throw new DataProcessingException("Expected to insert at lest " + + "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 add new book" + book,e); + } + return book; + } + + @Override + public Optional findById(Long id) { + String sql = "SELECT * FROM books WHERE id = ?"; + Book book = null; + try (Connection connection = ConnectionUtil.getConnection(); + PreparedStatement statement = connection.prepareStatement(sql)) { + statement.setLong(1, id); + ResultSet resultSet = statement.executeQuery(); + if (resultSet.next()) { + book = getBook(resultSet); + } + } catch (SQLException e) { + throw new DataProcessingException("Can not find bok by id: " + id, e); + } + return Optional.empty(); + } + + @Override + public List findAll() { + String sql = "SELECT * FROM books"; + List books = new ArrayList<>(); + + try (Connection connection = ConnectionUtil.getConnection(); + PreparedStatement statement = connection.prepareStatement(sql)) { + ResultSet resultSet = statement.executeQuery(); + while (resultSet.next()) { + books.add(getBook(resultSet)); + } + } catch (SQLException e) { + throw new DataProcessingException("Can not get books from DB", e); + } + return books; + } + + @Override + public Book update(Book book) { + String sql = "UPDATE books SET title = ?, price = ? WHERE id = ?"; + try (Connection connection = ConnectionUtil.getConnection(); + PreparedStatement statement = connection.prepareStatement(sql)) { + statement.setString(1, book.getTitle()); + statement.setBigDecimal(2, book.getPrice()); + statement.setLong(3, book.getId()); + statement.executeUpdate(); + } catch (SQLException e) { + throw new DataProcessingException("Can not update book: " + book, e); + } + return book; + } + + @Override + public boolean deleteById(Long id) { + String sql = "DELETE FROM books WHERE id = ?"; + + try (Connection connection = ConnectionUtil.getConnection(); + PreparedStatement statement = connection.prepareStatement(sql)) { + statement.setLong(1, id); + return statement.executeUpdate() > 0; + } catch (SQLException e) { + throw new DataProcessingException("Can not delete book where 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.getObject("price", BigDecimal.class); + Book book = new Book(); + book.setId(id); + book.setTitle(title); + book.setPrice(price); + return book; + } +} diff --git a/src/main/java/mate/academy/exception/DataProcessingException.java b/src/main/java/mate/academy/exception/DataProcessingException.java new file mode 100644 index 00000000..4996b171 --- /dev/null +++ b/src/main/java/mate/academy/exception/DataProcessingException.java @@ -0,0 +1,11 @@ +package mate.academy.exception; + +public class DataProcessingException extends RuntimeException { + public DataProcessingException(String massage) { + super(massage); + } + + public DataProcessingException(String message, Throwable cause) { + super(message, cause); + } +} diff --git a/src/main/java/mate/academy/lib/Dao.java b/src/main/java/mate/academy/lib/Dao.java index f558d09a..8d0b19fc 100644 --- a/src/main/java/mate/academy/lib/Dao.java +++ b/src/main/java/mate/academy/lib/Dao.java @@ -1,8 +1,11 @@ package mate.academy.lib; +import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; +import java.lang.annotation.Target; @Retention(RetentionPolicy.RUNTIME) +@Target(ElementType.TYPE) public @interface Dao { } diff --git a/src/main/java/mate/academy/model/Book.java b/src/main/java/mate/academy/model/Book.java new file mode 100644 index 00000000..51f5a6a3 --- /dev/null +++ b/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 String getTitle() { + return title; + } + + public BigDecimal getPrice() { + return price; + } + + public void setId(Long id) { + this.id = id; + } + + public void setTitle(String title) { + this.title = title; + } + + public void setPrice(BigDecimal price) { + this.price = price; + } + + @Override + public String toString() { + return "Book{" + + "id=" + id + + ", title='" + title + '\'' + + ", price=" + price + + '}'; + } +} diff --git a/src/main/java/mate/academy/util/ConnectionUtil.java b/src/main/java/mate/academy/util/ConnectionUtil.java new file mode 100644 index 00000000..85eed507 --- /dev/null +++ b/src/main/java/mate/academy/util/ConnectionUtil.java @@ -0,0 +1,26 @@ +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", "root1234"); + try { + Class.forName("com.mysql.cj.jdbc.Driver"); + } catch (ClassNotFoundException e) { + throw new RuntimeException("Can not load JDBC driver", e); + } + } + + public static Connection getConnection() throws SQLException { + return DriverManager.getConnection(DB_URL,DB_PROPERTIES); + } +} diff --git a/src/main/resources/init_db.sql b/src/main/resources/init_db.sql new file mode 100644 index 00000000..61125974 --- /dev/null +++ b/src/main/resources/init_db.sql @@ -0,0 +1,7 @@ +DROP TABLE IF EXISTS books; + +CREATE TABLE books ( + id INT AUTO_INCREMENT PRIMARY KEY, + title VARCHAR(255) NOT NULL, + price DECIMAL(10, 2) NOT NULL +); \ No newline at end of file