方法可以重寫,變量可以嗎
測試類:
public?class?Initail?{
????public?static?void?main(String[]?args)?{
????????Phone?phone?=?new?Phone();
????????SmartPhone?smartPhone?=?new?SmartPhone();
????????phone.call();
????????smartPhone.call();
????????phone.printTarget();
????????smartPhone.printTarget();
????}
}父類
public?class?Phone?{
????String?target?=?"me";
????public?void?call(){
????????System.out.println("You?call?to?"+this.target);
????}
????public?void?printTarget(){
????????System.out.println(this.target);
????}
}子類
public?class?SmartPhone?extends?Phone?{
????//String?target?=?"notme";
????//不寫這一行,this.target?為父類中的me
????public?void?call(){
????????System.out.println("You?call?to?"+this.target);
????}
????public?void?printTarget(){
????????System.out.println(this.target);
????}
}此時運行smartPhone.printTarget()的結果為me,在該類里沒有target變量,它卻識別到了父類里的target,但如果去掉注釋,他就會使用子類的target,這算是一種重寫嗎?按理說不可以定義重名的變量,那么是重寫了(子類有target變量,被覆寫為notme),還是說目前的子類中沒有target變量,變量是父類的呢?(類似于子類沒有target存在時,target 就相當于是 super.target)
2021-01-04
是一種重寫
2020-09-14
變量不可以重寫