java & operator with two integers?

java bitwise-operators bitwise-and
nife552 picture nife552 · Dec 18, 2013 · Viewed 20.5k times · Source

From what I understand the & operator is similar to the && operator except that the && only checks the second if the first is true, while the & checks both regardless of the result of the first one. Basically the && just saves a little time and power.

If that is so, then how does this code work?

int l = 0;
if ((l & 8) != 0 && (l & 4) == 0){ do something}

what does the (l & 8) and the (l & 4) do? What does the & do in this case?

Answer

Raffaele Rossi picture Raffaele Rossi · Dec 18, 2013

& and && are two different operators but the difference is not what you've described.

& does the bit-wise AND of two integers and produces a third integer whose bit are set to 1 if both corresponding bits in the two source integers are both set to 1; 0 otherwise.

&& applies only to two booleans and returns a third boolean which will be true if both the input booleans are true; false otherwise.

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