Questions and answers for exam Preparation

MCQs

Total Questions : 30 | Page 3 of 3 pages

Question 21. What is the output for the below code ?1. public class A{2. int add(int i, int j){3. return i+j;4. }5. }6. public class B extends A{7. public static void main(String argv[]){8. short s = 9;9. System.out.println(add(s,6));10. }11.}

15
None of these
Compile fail due to error on line no 2
Compile fail due to error on line no 9
Compile fail due to error on line no 8

Discuss Question

Answer: Option D. -> Compile fail due to error on line no 9

Question 22. Determine output:public class Test{ public static void main(String args[]){ MyClass obj = new MyClass(); obj.val = 1; obj.call(obj); System.out.println(obj.val); }}class MyClass{ public int val; public void call(MyClass ref){ ref.val++; }}

None of these
Compilation Error
1
3
2

Discuss Question

Answer: Option E. -> 2

Question 23. Class MyClass{ MyClass(){ System.out.print("one"); } public void myMethod(){ this(); System.out.print("two"); }} public class TestClass{ public static void main(String args[]){ MyClass obj = new MyClass(); obj.myMethod(); }}

one one two
Compilation Error
one Exception
two one one
None of these

Discuss Question

Answer: Option B. -> Compilation Error

Question 24. Public class MyClass{ }For the above class(MyClass) what is the correct way of declaring constructor?

public MyClass(){}
MyClass(void) {}
MyClass(){}
1 and 3
public MyClass(void){}

Discuss Question

Answer: Option D. -> 1 and 3

Question 25. Class MyClass{int i;int j;public MyClass(int i, int j){this.i = i;this.j = j;}public void call(){System.out.print("One");}}public class Test{public static void main(String args[]){MyClass m = new MyClass(); //line 1m.call(); //line 2}}

Compilation fails due to an error on line 1
Compilation succeed but no output.
Compilation fails due to an error on line 2
One

Discuss Question

Answer: Option A. -> Compilation fails due to an error on line 1

Question 26. Class A{ A(String s){} A(){}}1. class B extends A{2. B(){}3. B(String s){4. super(s);5. }6. void test(){7. // insert code here8. }9. }Which of the below code can be insert at line 7 to make clean compilation ?

A a = new A(String s);
A a = new B(5);
All of these
A a = new B();
None of these

Discuss Question

Answer: Option D. -> A a = new B();

Question 27. What is the output for the below code?public class Test{ public static void printValue(int i, int j, int k){ System.out.println("int"); } public static void printValue(byte...b){ System.out.println("long"); } public static void main(String... args){ byte b = 9; printValue(b,b,b); }}

Compilation clean but throws RuntimeException
None of these
int
Compilation fails
long

Discuss Question

Answer: Option C. -> int

Question 28. What is the output for the below code ?class A{ public A(){ System.out.println("A"); } public A(int i){ this(); System.out.println(i); }}class B extends A{ public B(){ System.out.println("B"); } public B(int i){ this(); System.out.println(i+3); }}public class Test{ public static void main (String[] args){ new B(5); }}

A B 8
None of these
B 8 A 5
A 5 B 8
A B 5

Discuss Question

Answer: Option A. -> A B 8

Question 29. What will be the result of compiling and running the given code?class A{ int b=10; private A(){ this.b=7; } int f(){ return b; }}class B extends A{ int b;}public class Test{ public static void main(String[] args){ A a = new B(); System.out.println(a.f()); }}

Compilation Fails
Prints 0
Prints 7
None of these
Prints 10

Discuss Question

Answer: Option A. -> Compilation Fails

Question 30. Which of these is a legal definition of a method named examveda assuming it throws IOException, and returns void. Also assume that the method does not take any arguments. Select the one correct answer.