feature: #1319 add table module pattern (#1742)

* modify table module pattern

* fix code smells

* resolve conversation

Co-authored-by: tao-sun2 <sustc18st@gmai.com>
Co-authored-by: Ilkka Seppälä <iluwatar@users.noreply.github.com>

table-module/src/main/java/com/iluwatar/tablemodule/App.java

@@ -0,0 +1,81 @@
+package com.iluwatar.tablemodule;
+
+import java.sql.SQLException;
+import javax.sql.DataSource;
+
+import lombok.extern.slf4j.Slf4j;
+import org.h2.jdbcx.JdbcDataSource;
+
+
+/**
+ * Table Module pattern is a domain logic pattern.
+ * In Table Module a single class encapsulates all the domain logic for all
+ * records stored in a table or view. It's important to note that there is no
+ * translation of data between objects and rows, as it happens in Domain Model,
+ * hence implementation is relatively simple when compared to the Domain
+ * Model pattern.
+ *
+ * <p>In this example we will use the Table Module pattern to implement register
+ * and login methods for the records stored in the user table. The main
+ * method will initialise an instance of {@link UserTableModule} and use it to
+ * handle the domain logic for the user table.</p>
+ */
+@Slf4j
+public final class App {
+  private static final String DB_URL = "jdbc:h2:~/test";
+
+  /**
+   * Private constructor.
+   */
+  private App() {
+
+  }
+
+  /**
+   * Program entry point.
+   *
+   * @param args command line args.
+   * @throws SQLException if any error occurs.
+   */
+  public static void main(final String[] args) throws SQLException {
+    // Create data source and create the user table.
+    final var dataSource = createDataSource();
+    createSchema(dataSource);
+    var userTableModule = new UserTableModule(dataSource);
+
+    // Initialize two users.
+    var user1 = new User(1, "123456", "123456");
+    var user2 = new User(2, "test", "password");
+
+    // Login and register using the instance of userTableModule.
+    userTableModule.registerUser(user1);
+    userTableModule.login(user1.getUsername(), user1.getPassword());
+    userTableModule.login(user2.getUsername(), user2.getPassword());
+    userTableModule.registerUser(user2);
+    userTableModule.login(user2.getUsername(), user2.getPassword());
+
+    deleteSchema(dataSource);
+  }
+
+  private static void deleteSchema(final DataSource dataSource)
+          throws SQLException {
+    try (var connection = dataSource.getConnection();
+         var statement = connection.createStatement()) {
+      statement.execute(UserTableModule.DELETE_SCHEMA_SQL);
+    }
+  }
+
+  private static void createSchema(final DataSource dataSource)
+          throws SQLException {
+    try (var connection = dataSource.getConnection();
+         var statement = connection.createStatement()) {
+      statement.execute(UserTableModule.CREATE_SCHEMA_SQL);
+    }
+  }
+
+  private static DataSource createDataSource() {
+    var dataSource = new JdbcDataSource();
+    dataSource.setURL(DB_URL);
+    return dataSource;
+  }
+}