Integer/Boolean Conditional-Or Operator ||

This Java operator when used as follows is called the conditional-or operator. This section is included here so that you can understand both the conditional-or operator and the escalation operator, which use the same symbol.

The || operator is like | but evaluates its right-hand operand only if the value of its left-hand operand is false. It is syntactically left-associative (it groups left-to-right). It is fully associative with respect to both side effects and result value; that is, for any expressions a, b, and c, evaluation of the expression ((a)||(b))||(c) produces the same result, with the same side effects occurring in the same order, as evaluation of the expression (a)||((b)||(c)).

								ConditionalOrExpression:
												ConditionalAndExpression
												ConditionalOrExpression || ConditionalAndExpression

Each operand of || must be of type Boolean, or a parse-time error occurs. The type of a conditional-or expression is always Boolean.

At run time, the left-hand operand expression is evaluated first; if its value is true, the value of the conditional-or expression is true and the right-hand operand expression is not evaluated. If the value of the left-hand operand is false, then the right-hand expression is evaluated and its value becomes the value of the conditional-or expression.

Thus, || computes the same result as | on Boolean operands. It differs only in that the right-hand operand expression is evaluated conditionally rather than always.