What does this output?
class Base {
int x = 10;
int getX() { return x; }
}
class Derived extends Base {
int x = 20;
int getX() { return x; }
}
Base obj = new Derived();
System.out.println(obj.x);
System.out.println(obj.getX());

Question

What does this output?
class Base {
  int x = 10;
  int getX() { return x; }
}
class Derived extends Base {
  int x = 20;
  int getX() { return x; }
}
Base obj = new Derived();
System.out.println(obj.x);
System.out.println(obj.getX());

Accepted Answer

Fields are resolved statically based on the declared reference type (no polymorphism for fields), so obj.x accesses Base's x = 10. Methods are resolved dynamically based on the actual object type (polymorphism), so obj.getX() calls Derived's override, returning 20.

What does this output? class Base { int x = 10; int getX() { return x; } } class Derived extends Base { int x = 20; int getX() { return x; } } Base obj = new Derived(); System.out.println(obj.x); System.out.println(obj.getX());

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