ibps-so 2016 · Question 6 of 394

The reconciliation utility compares the instrument numbers returned by two systems. The reviewer has objected that the comparison is written with the identity operator upon boxed values rather than with equals, and the author has replied that it has always worked. The committee has asked for the actual output of the following fragment, which uses one pair of small values and one pair of larger ones. Integer a = 127, b = 127; Integer c = 128, d = 128; System.out.println((a == b) + " " + (c == d) + " " + c.equals(d)); The output of the fragment is:

1. Atrue true true — identity upon a wrapper always follows the value it wraps
2. Btrue false true — identity holds for 127, which lies within the cached range, but not for 128, which does not, while equals compares the wrapped values themselvesCorrect
3. Cfalse false true — identity upon a wrapper never follows the value it wraps
4. Dtrue false false — equals upon a wrapper compares references exactly as == does
5. Efalse true true — the cache holds the larger values and not the smaller ones