Application.scala

package controllers

import javax.inject._
import play.api._
import play.api.db.Database
import play.api.mvc._
import org.jscience.physics.amount.Amount
import org.jscience.physics.model.RelativisticModel
import javax.measure.unit.SI

@Singleton
class Application @Inject()(val controllerComponents: ControllerComponents, val database: Database) extends BaseController {

  def index(): Action[AnyContent] = Action { implicit request: Request[AnyContent] =>
    Ok(views.html.index())
  }

  def convert(): Action[AnyContent] = Action { implicit request: Request[AnyContent] =>
    RelativisticModel.select()
    val energy = Amount.valueOf("12 GeV");

    Ok("E=mc^2: " + energy + " = " + energy.to(SI.KILOGRAM))
  }

  def db(): Action[AnyContent] = Action { implicit request: Request[AnyContent] =>
    // In this getting started app, we don't use a custom execution context to keep the code and configuration simple.
    // For real-world apps, consult the Play documentation on how to configure custom contexts and how to use them:
    // https://www.playframework.com/documentation/2.8.19/AccessingAnSQLDatabase#Using-a-CustomExecutionContext
    database.withConnection { connection =>
      val statement = connection.createStatement()
      statement.executeUpdate("CREATE TABLE IF NOT EXISTS ticks (tick timestamp)")
      statement.executeUpdate("INSERT INTO ticks VALUES (now())")

      val output = new StringBuilder();
      val resultSet = statement.executeQuery("SELECT tick FROM ticks")
      while (resultSet.next()) {
        output.append("Read from DB: " + resultSet.getTimestamp("tick") + "\n")
      }

      Ok(output.toString())
    }
  }
}