If statement executing all conditions

Question

This may actually be a silly question but I am wondering if it is possible to have an if statement executing all conditions. I explain:

if (methodA() && methodB() && methodC()) {code}

code is executed when all three methods return true. The point is that when a method returns false, the rest of the methods aren't executed. This is normally a good thing for performance but what if I really need to execute all methods independently of what they are returning and after that evaluate the expression and go into the if or not. The same is applied for OR or whatever

Is there a way to tell java to behave that way? My current work around is to split it in three ifs but this not always does the trick and looks really ugly.

Yes, if the method return types are boolean. Then use `&` instead of `&&`. `&&` means if the first one is false stop, `&` will continue on regardless. — Peter_James, Nov 21 '13 at 10:45
You can also simply assign the result of your methods in a variable and evaluate those variable in your condition — benzonico, Nov 21 '13 at 10:47

score 29 · Accepted Answer · answered Nov 21 '13 at 10:46

29

That’s quite simple: use the & operator instead of &&.

From: http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.23

The conditional-and operator && is like & (§15.22.2), but evaluates its right-hand operand only if the value of its left-hand operand is true.

answered Nov 21 '13 at 10:46

Holger

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You can explain the difference, please? – MeNa Nov 21 '13 at 10:48
wht to use only & but not && – Invader Nov 21 '13 at 10:50
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See my first comment under the question "&& means if the first one is false it will stop trying the next methods, & will continue to try the next methods regardless." – Peter_James Nov 21 '13 at 10:50
@user2860598 - Quite ironic that you yourself didn't incorporate this in your answer. I suggest you do it. – Rahul Nov 21 '13 at 10:55
This is valid for Python too – Dennis Feb 17 '21 at 18:32

Kevin Bowersox · Answer 2 · 2013-11-21T10:51:50.243

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Use the bitwise & operator, which evaluates both sides of the condition and stops the conditional from short circuiting. As you have noticed the && and || conditional operators will short circuit once the result of the expression can be determined.

if (methodA() & methodB() & methodC()) {code}

Documentation

edited Nov 21 '13 at 10:51

answered Nov 21 '13 at 10:46

Kevin Bowersox

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score 3 · Answer 3 · answered Nov 21 '13 at 10:51

try this

& is bitwise. && is logical.

 & evaluates both sides of the operation.
 && evaluates the left side of the operation, if it's true, it continues and evaluates the right side.

for fast execution use && if (methodA() & methodB() & methodC()) {code}

Michael Kazarian · Answer 4 · 2013-11-21T11:10:06.443

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You should use bitwise AND (&) operator instead of logical AND (&&).

if (methodA() & methodB() & methodC()) {code}

More detail read here.

edited Nov 21 '13 at 11:10

answered Nov 21 '13 at 10:47

Michael Kazarian

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score 2 · Answer 5 · answered Nov 21 '13 at 10:48

2

Your exact answer is:

if (methodA() & methodB() & methodC()) {code}

answered Nov 21 '13 at 10:48

Peter_James

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Shoaib Chikate · Answer 6 · 2013-11-21T15:11:43.360

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Use Bitwise AND instead of &&

   if (methodA() & methodB() & methodC()) {code}

edited Nov 21 '13 at 15:11

answered Nov 21 '13 at 10:48

Shoaib Chikate

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score 0 · Answer 7 · answered Nov 21 '13 at 10:57

Just change && to &. So your answer is

if (methodA() & methodB() & methodC()) {code}

&&is a comparison. It means the if statement will check the methodA() && methodB() conditional first. If this return false, then the methodC() will not execute. If true, then it will check with the methodC() function.

& is a bitwise. It will return true if all the value is 1. methodA() & methodB() & methodC() count as one comparison. So it will run through all the function. And then check if the answer is true or false.

score 0 · Answer 8 · answered Nov 21 '13 at 11:01

Another solution (but not that elegant) would be to use boolean variables:

boolean resA = methodA();
boolean resB = methodB();
boolean resC = methodC();

then do your ifs:

if (resA && resB && resC) { code }

That way your methods will run, and you just need to compare what they returned.

score 0 · Answer 9 · answered Apr 22 '22 at 20:08

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For kotlin users

if (methodA() and methodB() and methodC()) {code}

answered Apr 22 '22 at 20:08

niranjan kurambhatti

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If statement executing all conditions

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