1 下载IDEA以及scala sdk

http://www.jetbrains.com/idea/download/download-thanks.html?code=IIC

http://www.scala-lang.org/download/

2 DEA安装scala插件

file->settings->plugins

输入scala，然后点击install

完成后重启IDEA

新建scala工程，选择scala sdk位置

3 helloworld代码

进入主界面后，新建scala文件hello，文件类型选择object

object hello {
  def main(args: Array[String]): Unit = {
    say_hello()
  }
  def say_hello(): Unit ={
    println("hello")
  }
}