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Generics in HashSet add operation.  RSS feed

 
Nicholas Jordan
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I have the following declaration:



The add operation will not compile. I tried several forms and read HashSet, I get:
 
Jim Yingst
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Your declaration is for a variable "s", while the error message is about code related to a variable called "set". Apparently both of these are Sets, and you seem to think that they have something to do with each other. But I suspect that the compiler considers "s" and "set" to be two different things. Perhaps you could show us the declaration for "set" instead?

More to the point, what on earth is NextObject? It looks like a class or interface name, but you seem to be using it as a variable. Of course the compiler doesn't care if you disregard standard naming conventions, but you do need to define this NextObject thing somewhere. I'm guessing that whatever it is, it's not a String, and that's why the compiler is complaining.
 
Nicholas Jordan
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Tool completed successfully

Got it, working too fast. Short utility coded from lamer implementation on a security site used a line number reader to construct a port number, string pair and I had coded the HashSet as being Strings, changed it to the type that is actually being added in the HashSet.add(Object) and the compiler reported as above.
 
It is sorta covered in the JavaRanch Style Guide.
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