java-design-patterns/table-module/src/main/java/com/iluwatar/tablemodule/UserTableModule.java

/*
 * 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.tablemodule;

import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import lombok.extern.slf4j.Slf4j;


/**
 * This class organizes domain logic with the user table in the
 * database. A single instance of this class contains the various
 * procedures that will act on the data.
 */
@Slf4j
public class UserTableModule {
  /**
   * Public element for creating schema.
   */
  public static final String CREATE_SCHEMA_SQL =
          "CREATE TABLE IF NOT EXISTS USERS (ID NUMBER, USERNAME VARCHAR(30) "
                  + "UNIQUE,PASSWORD VARCHAR(30))";
  /**
   * Public element for deleting schema.
   */
  public static final String DELETE_SCHEMA_SQL = "DROP TABLE USERS IF EXISTS";
  private final DataSource dataSource;


  /**
   * Public constructor.
   *
   * @param userDataSource the data source in the database
   */
  public UserTableModule(final DataSource userDataSource) {
    this.dataSource = userDataSource;
  }


  /**
   * Login using username and password.
   *
   * @param username the username of a user
   * @param password the password of a user
   * @return the execution result of the method
   * @throws SQLException if any error
   */
  public int login(final String username, final String password)
          throws SQLException {
    var sql = "select count(*) from USERS where username=? and password=?";
    ResultSet resultSet = null;
    try (var connection = dataSource.getConnection();
         var preparedStatement =
                 connection.prepareStatement(sql)
    ) {
      var result = 0;
      preparedStatement.setString(1, username);
      preparedStatement.setString(2, password);
      resultSet = preparedStatement.executeQuery();
      while (resultSet.next()) {
        result = resultSet.getInt(1);
      }
      if (result == 1) {
        LOGGER.info("Login successfully!");
      } else {
        LOGGER.info("Fail to login!");
      }
      return result;
    } finally {
      if (resultSet != null) {
        resultSet.close();
      }
    }
  }

  /**
   * Register a new user.
   *
   * @param user a user instance
   * @return the execution result of the method
   * @throws SQLException if any error
   */
  public int registerUser(final User user) throws SQLException {
    var sql = "insert into USERS (username, password) values (?,?)";
    try (var connection = dataSource.getConnection();
         var preparedStatement =
                 connection.prepareStatement(sql)
    ) {
      preparedStatement.setString(1, user.getUsername());
      preparedStatement.setString(2, user.getPassword());
      var result = preparedStatement.executeUpdate();
      LOGGER.info("Register successfully!");
      return result;
    }
  }
}