Polymorphism

AP Computer Science A· difficulty 2/5

public class A {
    public String name() { return "A"; }
}
public class B extends A {
    public String name() { return "B"; }
}
// Usage:
A obj = new B();
System.out.print(obj.name());

What is printed?

A
$AB$
B
$B$
check_circle
C
$Compile error$
D
$A$

Explanation

Method dispatch in Java is based on the runtime (actual) type of the object, not the declared type. obj refers to a B object, so B's name() is called, printing "B".

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