/* * This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt). * * The MIT License * Copyright © 2014-2022 Ilkka Seppälä * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package com.iluwatar.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Optional; import java.util.Spliterator; import java.util.Spliterators; import java.util.function.Consumer; import java.util.stream.Stream; import java.util.stream.StreamSupport; import javax.sql.DataSource; import lombok.RequiredArgsConstructor; import lombok.extern.slf4j.Slf4j; /** * An implementation of {@link CustomerDao} that persists customers in RDBMS. */ @Slf4j @RequiredArgsConstructor public class DbCustomerDao implements CustomerDao { private final DataSource dataSource; /** * Get all customers as Java Stream. * * @return a lazily populated stream of customers. Note the stream returned must be closed to free * all the acquired resources. The stream keeps an open connection to the database till it is * complete or is closed manually. */ @Override public Stream getAll() throws Exception { try { var connection = getConnection(); var statement = connection.prepareStatement("SELECT * FROM CUSTOMERS"); // NOSONAR var resultSet = statement.executeQuery(); // NOSONAR return StreamSupport.stream(new Spliterators.AbstractSpliterator(Long.MAX_VALUE, Spliterator.ORDERED) { @Override public boolean tryAdvance(Consumer action) { try { if (!resultSet.next()) { return false; } action.accept(createCustomer(resultSet)); return true; } catch (SQLException e) { throw new RuntimeException(e); // NOSONAR } } }, false).onClose(() -> mutedClose(connection, statement, resultSet)); } catch (SQLException e) { throw new CustomException(e.getMessage(), e); } } private Connection getConnection() throws SQLException { return dataSource.getConnection(); } private void mutedClose(Connection connection, PreparedStatement statement, ResultSet resultSet) { try { resultSet.close(); statement.close(); connection.close(); } catch (SQLException e) { LOGGER.info("Exception thrown " + e.getMessage()); } } private Customer createCustomer(ResultSet resultSet) throws SQLException { return new Customer(resultSet.getInt("ID"), resultSet.getString("FNAME"), resultSet.getString("LNAME")); } /** * {@inheritDoc} */ @Override public Optional getById(int id) throws Exception { ResultSet resultSet = null; try (var connection = getConnection(); var statement = connection.prepareStatement("SELECT * FROM CUSTOMERS WHERE ID = ?")) { statement.setInt(1, id); resultSet = statement.executeQuery(); if (resultSet.next()) { return Optional.of(createCustomer(resultSet)); } else { return Optional.empty(); } } catch (SQLException ex) { throw new CustomException(ex.getMessage(), ex); } finally { if (resultSet != null) { resultSet.close(); } } } /** * {@inheritDoc} */ @Override public boolean add(Customer customer) throws Exception { if (getById(customer.getId()).isPresent()) { return false; } try (var connection = getConnection(); var statement = connection.prepareStatement("INSERT INTO CUSTOMERS VALUES (?,?,?)")) { statement.setInt(1, customer.getId()); statement.setString(2, customer.getFirstName()); statement.setString(3, customer.getLastName()); statement.execute(); return true; } catch (SQLException ex) { throw new CustomException(ex.getMessage(), ex); } } /** * {@inheritDoc} */ @Override public boolean update(Customer customer) throws Exception { try (var connection = getConnection(); var statement = connection .prepareStatement("UPDATE CUSTOMERS SET FNAME = ?, LNAME = ? WHERE ID = ?")) { statement.setString(1, customer.getFirstName()); statement.setString(2, customer.getLastName()); statement.setInt(3, customer.getId()); return statement.executeUpdate() > 0; } catch (SQLException ex) { throw new CustomException(ex.getMessage(), ex); } } /** * {@inheritDoc} */ @Override public boolean delete(Customer customer) throws Exception { try (var connection = getConnection(); var statement = connection.prepareStatement("DELETE FROM CUSTOMERS WHERE ID = ?")) { statement.setInt(1, customer.getId()); return statement.executeUpdate() > 0; } catch (SQLException ex) { throw new CustomException(ex.getMessage(), ex); } } }