26 JANUARY 2021 CURRENT AFFAIRS QUIZ

What will be the result of compiling and executing the following program code?class Vehicle{ public void printSound(){ System.out.print("vehicle"); }}class Car extends Vehicle{ public void printSound(){ System.out.print("car"); }}class Bike extends Vehicle{ public void printSound(){ System.out.print("bike"); }}public class Test{ public static void main(String[] args){ Vehicle v = new Car(); Bike b = (Bike) v; v.printSound(); b.printSound(); }}

"vehiclebike" is printed.

Compilation fails.

"vehiclecar" is printed.

"carcar" is printed.

ClassCastException exception is thrown at runtime.

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The concept of multiple inheritance is implemented in Java byI. Extending two or more classes.II. Extending one class and implementing one or more interfaces.III. Implementing two or more interfaces.

Only (I)

Only (III)

Only (II)

(I) and (II)

(II) and (III)

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What is the output of the following program code?abstract class C1{public C1(){ System.out.print(1); } } class C2 extends C1{ public C2(){ System.out.print(2); } } class C3 extends C2{ public C3(){ System.out.println(3); } } public class Test{ public static void main(String[] a){ new C3(); } }

12

23

321

123

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Which is true?

"X extends Y" is correct if X and Y are either both classes or both interfaces

"X extends Y" is correct for all combinations of X and Y being classes and/or interfaces

"X extends Y" is correct if and only if X is a class and Y is an interface

"X extends Y" is correct if and only if X is an interface and Y is a class

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Determine output:class Small{ public Small(){ System.out.print("a "); }}class Small2 extends Small{ public Small2(){ System.out.print("b "); }}class Small3 extends Small2{ public Small3(){ System.out.print("c "); }}public class Test{ public static void main(String args[]){ new Small3(); }}

c

The code runs without output..

a

a b c

c b a

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What is the result of compiling and running the following code?class Base{ public Base(){ System.out.print("Base"); }}public class Derived extends Base{ public Derived(){ this("Examveda"); System.out.print("Derived"); } public Derived(String s){ System.out.print(s); } public static void main(String[] args){ new Derived(); }}

Compilation Error

ExamiansBaseDerived

ExamiansDerived

ExamiansDerivedBase

BaseExamiansDerived

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What will be the result after compiling this code?class SuperClass{ public int doIt(String str, Integer... data)throws Exception{ String signature = "(String, Integer[])"; System.out.println(str + " " + signature); return 1; }}public class Test extends SuperClass{ public int doIt(String str, Integer... data){ String signature = "(String, Integer[])"; System.out.println("Overridden: " + str + " " +signature); return 0; } public static void main(String... args){ SuperClass sb = new Test(); sb.doIt("hello", 3); }}

Compilation fails

Overridden: hello (String, Integer[])

None of these

hello (String, Integer[])

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What will be the output?class Parent{ public void method(){ System.out.println("Hi i am parent"); }}public class Child extends Parent{ protected void method(){ System.out.println("Hi i am Child"); } public static void main(String args[]){ Child child = new Child(); child.method(); }}

Compiles successfully and print

None of This

Run Time error

Compile time error

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Determine output:class A{public void method1(){System.out.print("Class A method1");}}class B extends A{public void method2(){System.out.print("Class B method2");}}class C extends B{public void method2(){System.out.print("Class C method2");}public void method3(){System.out.print("Class C method3");}}public class Test{public static void main(String args[]){A a = new A();C c = new C();c.method2();a = c;a.method3();}}

None of these

Compilation Error

Runtime exception

Class C method2 Class C method3

Class B method2 Class C method3

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What will be the output?class One{ final int a = 15;}class Two extends One{ final int a = 20;}public class Test extends Two{ final int a = 30; public static void main(String args[]){ Test t = new One(); System.out.print(t.a); }}

20

None of these

30

Compiler Error

15

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YOUR ANSWER : ?