Null Boolean Values?

intejiaIdea null defintionNull boolean values. Can someone simplify the explanation in the photo.

I understand that we can set Boolean values to false or true using mathematical calculations or string setting, but am confused as to when a Boolean would ever be "Null" or "NotNull".
LVL 1
rgb192Asked:
Who is Participating?

Improve company productivity with a Business Account.Sign Up

x
Advertise Here
 
dpearsonConnect With a Mentor Commented:
In Java "bool" and "Boolean" are not quite equivalent.

"bool" is a primitive and only has 2 possible values - "true" or "false.
"Boolean" is an object and there can have 3 possible values - Boolean.TRUE, Boolean.FALSE or null.

e.g.
Boolean x = null ; // Legal
bool x = null ;  // Won't compile

That being said, this warning is actually saying that they've looked at your code and figured out that "m1 is always 3".

So B5 = (m1 != 3) ; will always be false (since m1 is always 3).  The null/non-null stuff isn't really coming into play in this instance - although it is good to understand them.

Hope that helps,

Doug
0
 
HuaMinChenBusiness AnalystCommented:
A boolean can be defaulted to 'false'. In your case, it is true when m1 does not equal to 3.
0
 
rgb192Author Commented:
true false null
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.