Java OCA OCP Practice Question 876

Question

Which of the following are output by this code? (Choose all that apply) 

3: String s = "Hello"; 
4: String t = new String(s); 
5: if ("Hello".equals(s)) System.out.println("one"); 
6: if (t == s) System.out.println("two"); 
7: if (t.equals(s)) System.out.println("three"); 
8: if ("Hello" == s) System.out.println("four"); 
9: if ("Hello" == t) System.out.println("five");
  • A. one
  • B. two
  • C. three
  • D. four
  • E. five
  • F. The code does not compile. 


A, C, D.

Note

The code compiles fine.

Line 3 points to the String in the string pool.

Line 4 calls the String constructor and is a different object than s.

Lines 5 and 7 check for object equality, which is true, and so print one and three.

Line 6 uses object reference equality, which is not true since we have different objects.

Line 7 compares references but is true since both references point to the object from the string pool.

Line 8 compares one object from the string pool with one that was constructed and returns false.




PreviousNext

Related