1z0-829 Exam - Question 12

Question

Given:What is the result?

Examice · Accepted Answer

Given the classes A, B, and C, where B extends A and C extends B, and examining the method calls made in the main method, we can deduce the output. The variable 'cobj' is declared as type A and instantiated as an object of class C. The 'if' condition checks whether 'cobj' is an instance of B, which is true because C is a subclass of B. Therefore, 'v.mB()' is called, which prints 'mB'. Next, it checks if 'v' is an instance of C, which is also true, so 'v1.mC()' is called, printing 'mC'. Thus, the final output is 'mB' followed by 'mC'.

supersquax · Answer

D is correct, verified in online java 17 compiler.

james2033 · Answer

package q12;

class A {
    public void mA() {
        System.out.println("mA");
    }
}

class B extends A {
    public void mB() {
        System.out.println("mB");
    }
}

class C extends B {
    public void mC() {
        System.out.println("mC");
    }
}

public class App {
    public static void main(String[] args) {
        A bobj = new B();
        A cobj = new C();
        if (cobj instanceof B v) {
            v.mB();
            if (v instanceof C v1) {
                v1.mC();
            } else {
                cobj.mA();
            }
        }
    }
}

// Result: 
// mB
// mC

minhdev · Answer

D is correct answer.

xplorerpj · Answer

D is correct answer

cobj instanceof B  == true , because class C extends B
v instanceof C == true, because here we compare class C instance to Class C instance

OutPut:
mB
mC

(Also tested the code by running)

Uteman · Answer

D is correct

1z0-829 Exam - Question 12

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