The parentheses are useless to the compiler because && takes precedence
over ||. The parentheses are useful to humans who have not memorized Java
operator precedence ;)
This warning is useful to catch weird style choices like "return (foo +
bar);" I've seen other odd choices in parentheses styling.
Gary
On Mon, May 13, 2013 at 11:09 AM, Nick Williams <
nicho...@nicholaswilliams.net> wrote:
> The PMD inspector says the following if statement contains "Useless
> parentheses."
>
> if ((isEventTimestamp && isLiteralValue) || (isEventTimestamp &&
> isPattern) || (isLiteralValue && isPattern)) {
> LOGGER.error("The pattern, literal, and isEventTimestamp
> attributes are mutually exclusive.");
> return null;
> }
>
> I'm all for removing useless parentheses; unfortunately, I don't see how
> these are useless. The way I see it, if isLiteralValue is false, with
> parentheses it will (correctly) continue to evaluate after the first
> grouped condition but without parentheses it would (incorrectly) short
> circuit after the first use of isLiteralValue.
>
> Am I missing something here? Or is this a PMD bug?
>
> Nick
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