valscores:scala.collection.mutable.Map[String, Int]=newjava.util.TreeMap[String, Int] 除此之外,你还能够得到从java.util.Properties到Map[String。String]的转换: import scala.collection.JavaConversions.propertiesAsScalaMap valprops:Scala.collection.Map[String, String] = System.getProperties() Scala到Jav...
下面的代码片段是一个简单的例子来定义所有上述集合类型: // Define List of integers.val x=List(1,2,3,4)// Define a set.varx=Set(1,3,5,7)// Define a map.val x=Map("one"->1,"two"->2,"three"->3)// Create a tuple of two elements.val x=(10,"Scala")// Define an optionv...
Map是一种键值对的集合,一般将其翻译为映射 //直接初始化 // ->操作符,左边是key,右边是value scala> val studentInfo=Map("john" -> 21, "stephen" -> 22,"lucy" -> 20) studentInfo: scala.collection.immutable.Map[String,Int] = Map(john -> 21, stephe n -> 22, lucy -> 20) //immut...
// Define a map.键/值对 val x = Map("one " -> 1, "two " -> 2, "three" -> 3) val colors = Map("red" -> "#FF0000", "azure" -> "#F0FFFF") // Create a tuple of two elements.元组可以容纳不同类型的对象 val x = (10, "Scala") val t = (1, "hello", Console) ...
Creating a Scala Map There are different syntax to define mutable and immutableScala maps, Syntax Syntax for creating immutable maps: map_name = Map(key_1 -> value_1, key_2 -> value_2, key_3 -> value_3) Syntax Syntax for creating mutable maps: ...
println("\nStep 2: Define another method which returns a Future") defbuyDonuts(quantity:Int):Future[Boolean]=Future{ println(s"buying $quantity donuts") true } 1. 2. 3. 4. 5. 上面我们又定义了一个方法,用来接收donutStock()的返回值,然后再返回一个Future[Boolean] 。
▲图1. 法雷奥的激光雷达概览 从2010年奥迪A8开始，之后还有本田和奔驰的车型，两代规格在于：● 电云...
▲图1. 法雷奥的激光雷达概览 从2010年奥迪A8开始，之后还有本田和奔驰的车型，两代规格在于：● 电云...
// define the case class case class Register(user: User) // create a new case class message val message = Register(user) 发送消息向actor发送消息需使用下列方法之一。!意思是“fire-and-forget”,即异步发送一个消息并立即返回。也称为tell。 ?异步发送一条消息并返回一个Future代表一个可能的回应。
Map操作实战 Map是一种键值对的集合,一般将其翻译为映射 //直接初始化// ->操作符,左边是key,右边是valuescala>valstudentInfo=Map("john"->21,"stephen"->22,"lucy"->20) studentInfo:scala.collection.immutable.Map[String,Int]=Map(john->21, stephe ...