Squeryl's KeyedEntityDef

KeyedEntityDefExample.scala

import org.squeryl.annotations.Column
import org.squeryl.PrimitiveTypeMode._
import org.squeryl.{ Session, SessionFactory, Schema, KeyedEntityDef }
import org.squeryl.adapters.{ PostgreSqlAdapter }
import java.util.Date

object KeyedEntityDefsExample extends App {

  class Member (
    val name: String,
    val instrument: String
  ) {
    override def toString = "Member(%s, %s, %s)".format(id, name, instrument)
    val id: Int = 0
  }

  object Beatles extends Schema {

    implicit object BeatlesKED extends KeyedEntityDef[Member, Int] {
      def getId(a: Member) = a.id
      def isPersisted(a: Member) = a.id > 0
      def idPropertyName = "id"
    }

    val member = table[Member]("member")
  }

  Class.forName("org.postgresql.Driver");

  def session = Session.create(
    java.sql.DriverManager.getConnection("jdbc:postgresql://localhost/beatles", "toshi", ""),
    new PostgreSqlAdapter {
      override def usePostgresSequenceNamingScheme: Boolean = true
    }
  )

  transaction(session) {
    val john = Beatles.member.insert(new Member("john", "guitar"))
    val paul = Beatles.member.insert(new Member("paul", "bass"))
    val george = Beatles.member.insert(new Member("George", "guitar"))
    val ringo = Beatles.member.insert(new Member("Ringo", "drums"))
    println(john)
    println(paul)
    println(george)
    println(ringo)
    /*
     Member(1, john, guitar)
     Member(2, paul, bass)
     Member(3, George, guitar)
     Member(4, Ringo, drums)
     */
  }

}

squeryl.KeyedEntityDef.sql

create table member (
  id serial primary key,
  name varchar(30) not null,
  instrument varchar(30) not null
);