SCJP題庫第064題
class A {
String name = "A";
String getName() {
return name;
}
String greeting(){
return "class A";
}
}
class B extends A {
String name = "B";
String greeting() {
return "class B";
}
}
__________________________________________
public class Client {
public static void main( String[] args ) {
A a = new A();
A b = new B();
System.out.println(a.greeting() + "has name" + a.getName());
System.out.println(b.greeting() + "has name" + b.getName());
}
}
Ans:
解說:
方法多形是說方法的決定是以物件為判斷的依據
b.getName()是叫用A型態的getName(因為B類別沒有getName)，所以A型態的getName就是取得A的name，若在B加上getName結果就不一樣了！
class A {
String name = "A";
String getName() {
return name;
}
String greeting(){
return "class A";
}
}
class B extends A {
String name = "B";
String getName() {
return name;
}
String greeting() {
return "class B";
}
}
public class Client {
public static void main( String[] args ) {
A a = new A();
A b = new B();
System.out.println(a.greeting() + "has name" + a.getName());
System.out.println(b.greeting() + "has name" + b.getName());
}
}
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