What is short-circuit operator in Java?

Question

Given 2 strings, a and b, return a string of the form shorterString+longerString+shorterString, with the shorter string on the outside and the longer string on the inside. The strings will not be the same length, but they may be empty (length 0). If input is "hi" and "hello", then output will be "hihellohi".

Answer 1

The logical operators && and || is known as short circuit operators in Java as they don't evaluate right-hand side until it is necessary. Example:

• false && (some expression): here evaluation of some expression is not necessary because F && (T) = False and compiler works smartly here.

• The Same case is with logical OR (||) operators, T || F = True but if it F || T then it will evaluate right-hand side expression too to check whether it is true or false.

Note: Don't confuse with bitwise AND and OR because both sides evaluated here as it performs operations on bit level of both side expressions.