[Checkers] Suggestions for NonNull checker warning messages

Mahmood Ali mahmood at MIT.EDU
Mon Apr 21 15:25:27 EDT 2008

On Apr 21, 2008, at 3:02 PM, Matt Papi wrote:

>> ./daikon/inv/unary/sequence/NoDuplicates.java:71: call to  
>> isLoggable(java.util.logging.Level) not allowed on the given  
>> receiver. [...]
>> Does it just mean that the receiver might be null?
> Yes, but this comes from functionality inherited from the framework
> that (in this case) is difficult to override.
I believe that this message is a result for double checking.  NonNull  
Checker checks for de-referencing null, and the framework checks for  
method invocation on null references.

Actually, you can simply override  
BaseTypeVisitor.checkMethodInvokability() to always return true to  
avoid the double checking.

>> 2. Another puzzling case is warnings like these:
>> [snip]
> All of those warnings are coming from the framework (which is also
> responsible for the placement of the "^"). The reason is not
> immediately obvious to me, but I'll take a look.
Do it have something to do with @NonNull not doing anything with  
binary trees?

More information about the checkers mailing list