Oracle Java SE 1Z0-819 Questions & Answers

• Question 251:

  Given the code fragment:

  

  What is the result?

  A. 01

  B. 0

  C. 1

  D. The program prints nothing.

  E. It prints 1 in the infinite loop.

  Correct Answer: D

• Question 252:

  Given:

  

  What is the result?

  A. A java.util.NoSuchElementException is thrown at run time.

  B. Ans : a

  C. The compilation fails.

  D. Ans :

  Correct Answer: A

• Question 253:

  Given the code fragment:

  

  What is the result?

  A. 13 5 7 9

  B. 1 3 5 7 9 11

  C. 2 4 6 B 10

  D. 2 4 6 8

  Correct Answer: B

• Question 254:

  Given:

  

  You wants to make the reduction operation parallelized. Which two modifications will accomplish this?

  A. Replace line 1 with int sum = numbers.stream() .flatMap(a -> a).reduce (0, (n, m) -> n + m);.

  B. Replace line 1 with int sum = numbers.stream().iterate (0, a -> a+1).reduce (0, (n, m) -> n + m)

  C. Replace line 1 with int sum = numbers.parallel ().stream().reduce(0, (n, m) -> n + m)

  D. Replace line 1 with int sum = numbers.parallelStream().reduce (0, (n, m) -> n + m);.

  E. Replace line 1 with int sum = numbers.stream().parallel().reduce(0, (n, m) -> n + m)

  Correct Answer: DE

• Question 255:

  Given: Which annotation should be used to remove warnings from compilation?

  

  A. @SuppressWarnings on the main and print methods

  B. @SuppressWarnings("unchecked") on main and @SafeVarargs on the print method

  C. @SuppressWarnings("rawtypes") on main and @SafeVarargs on the print method

  D. @SuppressWarnings("all") on the main and print methods

  Correct Answer: B

  

• Question 256:

  Given these two classes:

  

  And given this fragment:

  

  Which describes the fragment?

  A. It throws IllegalMonitorStateException.

  B. It is subject to deadlock.

  C. It is subject to livelock.

  D. The code does not compile.

  Correct Answer: B

• Question 257:

  Given:

  

  It is required that if p instanceof Pair then p.isValid() returns true.

  Which is the smallest set of visibility changes to insure this requirement is met?

  A. setLeft and setRight must be protected.

  B. left and right must be private.

  C. isValid must be public.

  D. left, right, setLeft, and setRight must be private.

  Correct Answer: D

  All methods of changing left and right must be private or a user in the same package could put it into a state where the validator returns false