Get superclass value in Java
•
Java
I have two classes:
public class A
{
int n = 10;
public int getN()
{
return n;
}
}
public class B extends A
{
int n = 20;
public int getN()
{
return n;
}
}
public class Test
{
public static void main(String[] args)
{
B b = new B();
System.out.println(b.getN()); //--> return 20
System.out.println(((A)b).getN()); //--> still return 20.
//How can I make it return 10?
}
}
Solution
All methods in Java are virtual That is, there is no way to call the "super" version of a method from outside Converting to a won't help because it won't change the runtime type of the object
This may be your best choice / solution:
class A {
int n = 10;
public int getN() {
return n;
}
public final int getSuperN() { // "final" to make sure it's not overridden
return n;
}
}
class B extends A {
int n = 20;
public int getN() {
return n;
}
}
public class Main {
public static void main(String[] args) {
B b = new B();
System.out.println(b.getN()); // --> return 20
System.out.println(((A)b).getN()); // --> still return 20.
System.out.println(b.getSuperN()); // --> prints 10
}
}
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