Scala简单的例子

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AnonymousFunc类如下所示：

package com.test.appobject AnonymousFunc {  def adder(m: Int, n: Int) = m + n //更简单的写法  def hello(x: Int) = x + 1 //简单的写法  val add2 = adder(2, _: Int) //_表示占位符  def multiply(m: Int)(n: Int): Int = m * n //优雅的写法  def main(args: Array[String]) {    println(add2(3))    println(multiply(2)(3))    val timesTwo = multiply(2)(_)    println(timesTwo(3))    var brand: String = "HP"  //命名规则类似于JAVA    val color: String = if (brand == "TI") {      "blue"    } else if (brand == "HP") {      "black"    } else {      "white"    }    println(color);      }}

PrintlnTest：

package com.test.appobject PrintlnTest {  def main(args: Array[String]) {    val array = Array(0, 1, 2, 3, 4, 5)    array.foreach(i => print(i))    println()    array.foreach(print(_))    println()    array.foreach(print)    println()    for (i <- 0 until 5) {      print(i)    }    println()    for (i <- 0 to 5) {      print(i)    }    println()    val map = Map(0 -> 0, 1 -> 1, 2 -> 2, 3 -> 3, 4 -> 4, 5 -> 5)    map.foreach {      case (key, value) => {        println("key:" + key + " value:" + value)      }    }    val array1 = Array(0, 1, 2, 3, 4, 5)    val array2 = Array(6, 7, 8, 9)    val array3 = array1 ++ array2    /**     * drop(n) 移除前n个元素     * take(n) 获取前n个元素     * filter(condition) 获取指定condition的元素     */    //array3.foreach(println)    array3.take(3).foreach(println)    // array3.drop(1).foreach(println)    //  array3.filter(_ != 1).foreach(println)    /**     * += 添加元素     * ++ 合并集合     */  }}

HelloScala：

package com.test.appobject HelloScala {  def main(args: Array[String]) {   //前10个数    var i = 0;    val rt =      for (        e <- ('a' to 'z') if { i = i + 1; i <= 10 }      ) printf("%d:\t%s\n", i, e)              //或者如下：      ('a' to 'z').slice(0,10).foreach(println)        //1 to 100 和小于1000的数      var (n,sum)=(0,0);         for(i<-0 to 100 if (sum+i<1000)) { n=i; sum+=i }  }}

ScalaObject：

package com.test.appobject ScalaObject {  //Map  val colors = Map("red" -> 0xFF0000,    "turquoise" -> 0x00FFFF,    "black" -> 0x000000,    "orange" -> 0xFF8040,    "brown" -> 0x804000)      //match case: 相当于swich case  def main(args: Array[String]) {    println("Hello, world! " + args.toList)    for (name <- args) println(      colors.get(name) match {        case Some(code) =>          name + " has code: " + code        case None =>          "Unknown color: " + name      })            colors.get("red")        }}