Condition evaluation process in Java

java if-statement compiler-construction jvm evaluation
Kevin Rave picture Kevin Rave · Jul 29, 2013 · Viewed 24.9k times · Source

Lets say I have the following condition:

if ( myList == null || myList.isEmpty() || xomeX == someY )

What is the order of the evaluation of these conditions? Left or right, right to left or random each time?

If the first one passes, then the others are ignored?

Answer

NINCOMPOOP picture NINCOMPOOP · Jul 29, 2013

It should be always be left to right except the assignment operator = . You are using short circuit OR operator , hence if the first condition is true , rest of them won't be evaluated.

JLS 15.24:

The conditional-or operator is syntactically left-associative (it groups left-to-right).

At run time, the left-hand operand expression is evaluated first; if the result has type Boolean, it is subjected to unboxing conversion (§5.1.8).

If the resulting value is true, the value of the conditional-or expression is true and the right-hand operand expression is not evaluated.

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