Conditional operator and if-else work different?

Question

This is not an error in Java 7

return (sum>9)? superDigit(sum,1): sum;

whereas

if(sum>9) superDigit(sum,1); 
else return sum;

this throws a "missing return statement" error. Why?

Brian H. · Accepted Answer · 2020-06-30 02:27:48Z

6

You're missing return statement in your if condition. Actually, it must be:

if(sum>9) 
    return superDigit(sum,1); 
else return sum;

or you can simplify:

if(sum>9) 
    return superDigit(sum,1); 
return sum;

answered Jun 30, 2020 at 2:27

Brian H.

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Comments

Neil · Accepted Answer · 2020-06-30 07:42:50Z

1

return (sum>9)? superDigit(sum,1): sum;

is ternary operator statement.The whole is one statement.

if(sum>9) superDigit(sum,1); else return sum;

is if/else conditional statement.Each conditional branch must be a complete statement or a stack of statements.

answered Jun 30, 2020 at 7:42

Neil

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