Scala 入门笔记-单例对象

在Scala中实现静态字段和静态方法的方式是用Object关键字来实现

1.工具类，存放常量和工具方法

2.实现单例模式

package day03

import scala.collection.mutable.ArrayBuffer

object SingletonDemo {
  def main(args: Array[String]): Unit = {
    val sessionFactory = SessionFactory

    println(sessionFactory.getSession)
    println(sessionFactory.getSession.size)
    println(sessionFactory.removeSession)
  }
}

object SessionFactory {
  println("SessionFactory")

  var i = 5

  private val session = new ArrayBuffer[Session]

  while (i > 0) {
    session += new Session
    i -= 1
  }

  def getSession = session

  def removeSession : Unit = {
    session.remove(0)
    println("session " + session(0) + " remove")
  }
}

class Session {}