Scala隐式转换

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package?com.lyzx.day18

class?SpecialMan(name:String){
??private?val?_name?=?name;

??def?display():?Unit?={
????println( "name="+_name)
??}
}

class?SuperMan(val?name:String){}
class?SpiderMan(val?name:String){}

class?CarMan(val?name:String){
??def?transformation()={println( "汽车人变形...")}
}


class?Car(val?name:String)

/*
??隐式准换
??1、把一个类准换为另一个类
??2、通过一个类调用另一个类的方法
* /
class?T2?{
???? //1、把一个类准换为另一个类
????def?f1(person:SpecialMan):?Unit?={
??????println( "f1......")
????}

}

object?T2{
?? /*
????隐式准换函数
????implicit?有隐式的意思
????当scala中的函数检查到传入的参数和定义的参数不同时会尝试着去执行隐式的转换
????scala会找所有前面加implicit的函数?尝试着将传入的参数准换为定义的参数
????T2.f1(...)的例子可以看到someting2SpecialMan执行(scala自动执行这个函数)
???* /
??implicit?def?someting2SpecialMan(obj:Object):?SpecialMan?=?{
????if?(obj.getClass?==?classOf[SuperMan])?{
??????println( "SuperMan->SpecialMan")
??????val?superMan?=?obj.asInstanceOf[SuperMan]
??????new?SpecialMan(superMan.name)
????}?else?if?(obj.getClass?==?classOf[SpiderMan])?{
??????println( "SpiderMan->SpecialMan")
??????val?spiderMan?=?obj.asInstanceOf[SpiderMan]
??????new?SpecialMan(spiderMan.name)
????}?else?{
??????null
????}
??}

??implicit?def?car2carMan(car:Object):?CarMan?={
????if(car.getClass?==?classOf[Car]){
??????println( "car->carMan")
??????val?carObj?=?car.asInstanceOf[Car]
??????return?new?CarMan(carObj.name)
????}else{
??????println( "car.getClass="+car.getClass)
??????println( "classOf[Car]="+classOf[Car])
??????println( "car->null")
??????return?null
????}
??}


??def?main(args:?Array[String])?{
????val?t2?=?new?T2
//????t2.f1(new?SpiderMan( ""))
//????t2.f1(new?SuperMan( ""))


???? /*
????当为f2方法传入Car类型的参数时,scala会尝试着把Car转换为CarMan?于是会尝试着执行car2carMan方法把Car转换为CarMan
????并调用
?????* /
????val?car?=?new?Car( "霸天虎") ????car.transformation() ??} }