#35 to #44 SCJP/OCJP Exams Questions & Answers-

35. Given:

22. StringBuilder sb1 = new StringBuilder("123");

23. String s1 = "123";

24. // insert code here

25. System.out.println(sb1 + " " + s1);

Which code fragment, inserted at line 24, outputs "123abc 123abc"?

A. sb1.append("abc"); s1.append("abc");

B. sb1.append("abc"); s1.concat("abc");

C. sb1.concat("abc"); s1.append("abc");

D. sb1.concat("abc"); s1.concat("abc");

E. sb1.append("abc"); s1 = s1.concat("abc");

F. sb1.concat("abc"); s1 = s1.concat("abc");

G. sb1.append("abc"); s1 = s1 + s1.concat("abc");

H. sb1.concat("abc"); s1 = s1 + s1.concat("abc");

Correct Answer: E

36. Which code, inserted at line 14, will allow this class to correctly serialize and deserialize?

import 

1.Import java.io.*;

2.public class foo implements Serialisable{

3.public int x,y;

4.public Foo(int x,int y){this.x=x;

    this.y=y;

5.  }

6.private void writeObject(

  ObjectOutputsStream s)

7.  throws IOException{

8.s.writeInt(x);

9. s.writeInt(y);

10.}

11.private void readObject(ObjectInputStream)

12 .throws IOException,ClassNotFoundException

13.{

14.//insert code here

15.

16.}

17.}

A. s.defaultReadObject();

B. this = s.defaultReadObject();

C. y = s.readInt(); x = s.readInt();

D. x = s.readInt(); y = s.readInt();

Correct Answer: D

37. Given:

1. public class LineUp {

2. public static void main(String[] args) {

3. double d = 12.345;

4. // insert code here

5. }

6. }

Which code fragment, inserted at line 4, produces the output | 12.345|?

A. System.out.printf("|%7d| \n", d);

B. System.out.printf("|%7f| \n", d);

C. System.out.printf("|%3.7d| \n", d);

D. System.out.printf("|%3.7f| \n", d);

E. System.out.printf("|%7.3d| \n", d);

F. System.out.printf("|%7.3f| \n", d);

Correct Answer: F

38. Given:

11. public class Test {

12. public static void main(String [] args) {

13. int x = 5;

14. boolean b1 = true;

15. boolean b2 = false;

16.

17. if ((x == 4) && !b2 )

18. System.out.print("1 ");

19. System.out.print("2 ");

20. if ((b2 = true) && b1 )

21. System.out.print("3 ");

22. }

23. }

What is the result?

A. 2

B. 3

C. 1 2

D. 2 3

E. 1 2 3

F. Compilation fails.

G. An exception is thrown at runtime.

Correct Answer: D

39. Given:

10. interface Foo {}

11. class Alpha implements Foo {}

12. class Beta extends Alpha {}

13. class Delta extends Beta {

14. public static void main( String[] args ) {

15. Beta x = new Beta();

16. // insert code here

17. }

18. }

Which code, inserted at line 16, will cause a java.lang.ClassCastException?

A. Alpha a = x;

B. Foo f = (Delta)x;

C. Foo f = (Alpha)x;

D. Beta b = (Beta)(Alpha)x;

Correct Answer: B

40. Given:

22. public void go() {

23. String o = "";

24. z:

25. for(int x = 0; x < 3; x++) {

26. for(int y = 0; y < 2; y++) {

27. if(x==1) break;

28. if(x==2 && y==1) break z;

29. o = o + x + y;

30. }

31. }

32. System.out.println(o);

33. }

What is the result when the go() method is invoked?

A. 00

B. 0001

C. 000120

D. 00012021

E. Compilation fails.

F. An exception is thrown at runtime.

Correct Answer: C

41.Given:

11. static void test() throws RuntimeException {

12. try {

13. System.out.print("test ");

14. throw new RuntimeException();

15. }

16. catch (Exception ex) { System.out.print("exception "); }

17. }

18. public static void main(String[] args) {

19. try { test(); }

20. catch (RuntimeException ex) { System.out.print("runtime "); }

21. System.out.print("end ");

22. }

What is the result?

A. test end

B. Compilation fails.

C. test runtime end

D. test exception end

E. A Throwable is thrown by main at runtime.

Correct  Answer: D

42. Given:

33. try {

34. // some code here

35. } catch (NullPointerException e1) {

36. System.out.print("a");

37. } catch (Exception e2) {

38. System.out.print("b");

39. } finally {

40. System.out.print("c");

41. }

If some sort of exception is thrown at line 34, which output is possible?

A. a

B. b

C. c

D. ac

E. abc

Correct  Answer: D

43. Given:

31. // some code here

32. try {

33. // some code here

34. } catch (SomeException se) {

35. // some code here

36. } finally {

37. // some code here

38. }

Under which three circumstances will the code on line 37 be executed? (Choose three.)

A. The instance gets garbage collected.

B. The code on line 33 throws an exception.

C. The code on line 35 throws an exception.

D. The code on line 31 throws an exception.

E. The code on line 33 executes successfully.

Correct Answer: B,C,E

44. Given:

10. int x = 0;

11. int y = 10;

12. do {

13. y--;

14. ++x;

15. } while (x < 5);

16. System.out.print(x + "," + y);

What is the result?

A. 5,6

B. 5,5

C. 6,5

D. 6,6

Correct Answer: B