Some notes on Elvis and Other Null-Safe Operators

Stephen Colebourne scolebourne at
Sat Apr 18 03:33:31 PDT 2009

Mark Mahieu wrote:
> Which doesn't seem like much of an improvement, to me.  But I keep  
> thinking that, in the context of this proposal, a null-safe form of  
> the foreach loop might not be so bad:
> 	for (Foo foo :? map?.get(key)) {
> 		...
> 	}

I certainly think thats an interesting idea.

However, having a null list is something that rarely comes up in the 
code I write. I think thats because I always return an empty list from 
methods and never null (something that is definitely good practice).

Where the null-safe operators come in is in handling object model 
structure such as a bean holding an optional value (String/Integer/Date 
etcc), or a bean holding another optional bean (person holding optional 
spouse). In these cases, holding null to represent the absence of data 
is a valid design choice.


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