Scala视图界定
1 package big.data.analyse.dataSet 2 3 /** 4 * 视图界定 5 * Created by zhen on 2018/11/29. 6 */ 7 /*class Pair_NotPerfect[T <: Comparable[T]](val first:T, val second:T){ //泛型 8 def bigger = if(first.compareTo(second) > 0)first else second 9 }*/ 10 class Pair_NotPerfect[T <% Comparable[T]](val first:T, val second:T){ //视图界定，支持隐式转换 11 def bigger = if(first.compareTo(second) > 0) first else second 12 } 13 14 class Pair_Better[T <% Ordered[T]](val first:T, val second:T){ //视图界定，支持隐式转换，支持操作符 15 def bigger = if(first > second) first else second 16 } 17 18 object Bound { 19 def main(args: Array[String]) { 20 val pair = new Pair_NotPerfect("Spark", "Hadoop") 21 println(pair.bigger) 22 23 val pairInt = new Pair_NotPerfect(3, 5) 24 println(pairInt.bigger) 25 26 val pair_Better = new Pair_Better("Solr", "Python") 27 println(pair_Better.bigger) 28 } 29 }
结果：
