open class CommonAction<T : Any> : ActionSupport(), ModelDriven<T>, ServletResponseAware {
      private var model: T// 声明模型对象
      override fun getModel(): T = model

      // 在运行期动态获得泛型的具体类型，并通过反射创建model对象
      init {//init代码块用于初始化参数,有了init代码块可以省略lateinit修饰符
          // 获得父类（CommonAction）对应的类型
          val genericSuperclass = this.javaClass.genericSuperclass as ParameterizedType
          // 获得父类上声明的泛型类型数组
          val actualTypeArguments = genericSuperclass.actualTypeArguments
          // 获得实体类型
          val entityClass = actualTypeArguments[0] as Class<*>
          // 通过反射创建model对象
          @Suppress("UNCHECKED_CAST")
          model = entityClass.newInstance() as T
      }
  //code here...
}

 private fun getAreas(wb: HSSFWorkbook): ArrayList<Area> {
        val sheet = wb.getSheetAt(0)

        val areas = arrayListOf<Area>()
        sheet.forEach rows@ {
            if (it.rowNum == 0) return@rows
            val area = Area()
            val province = it.getCell(1).stringCellValue
            val city = it.getCell(2).stringCellValue           
          //...
            area.shortcode = PinYin4jUtils.getHeadByString(province + city + district).joinToString("")
            area.citycode = PinYin4jUtils.hanziToPinyin(city, "")
            areas.add(area)
        }
        return areas
    }

 	//模型驱动对象直接返回
    private val order = Order()
    override fun getModel(): Order = order


    //基本数据类型好像可以不初始化,不初始化就给个lateinit
    open var page: Int = 0
    open var rows: Int = 0

    //引用数据类型给个lateinit等Struts注入就好,不用写setter干净利索
    lateinit var sendAreaInfo: String
    lateinit var recAreaInfo: String

val workBill = WorkBill().apply { 
                    attachbilltimes = 0
                    buildtime = Date()
                    courier = order.courier
                    this.order = order
                    pickstate = Constants.WORKBILLPICKSTATE_NEW
                    remark = order.remark
                    type = Constants.WORKBILLTYPE_NEW
                    smsNumber = order.sendMobile
                }

 		val isNull:String?=null
        println("isNull")
        println("isNullOrEmpty:${isNull.isNullOrEmpty()}")
        println("isNullOrBlank:${isNull.isNullOrBlank()}")
        println("===============================================")

        val isEmpty=""
        println("isEmpty")
        println("isNullOrEmpty:${isEmpty.isNullOrEmpty()}")
        println("isNullOrBlank:${isEmpty.isNullOrBlank()}")
        println("===============================================")

        val isSpace=" "
        println("isSpace")
        println("isNullOrEmpty:${isSpace.isNullOrEmpty()}")
        println("isNullOrBlank:${isSpace.isNullOrBlank()}")

        val s1="abc"
        val s2="ABc"
        println(s1.equals(s2,true))//equals方法有重载,第二个参数代表是否要忽略大小写
        println(s1.equals(s2,false))
        println(s1.equals(s2))//判断字符串时IDEA推荐用==不用equals方法