I have two double data elements in an object.
Sometimes they are set with a proper value and sometimes not. When the form field from which they values are received is not filled I want to set them to some value that tells me, during the rest of the code that the form fields were left empty.
I can't set the values to null as that gives an error, is there some way I can make them 'Undefined'.
PS. Not only am I not sure that this is possible, it might not also make sense. But if there is some best practice for such a situation I would be keen to hear it.
Two obvious options:
Double
instead of double
. You can then use null
, but you've changed the memory patterns involved substantially.Use a "not a number" (NaN) value:
double d = 5.5;
System.out.println(Double.isNaN(d)); // false
d = Double.NaN;
System.out.println(Double.isNaN(d)); // true
Note that some other operations on "normal" numbers could give you NaN values as well though (0 divided by 0 for example).