You have to love this: Mikael Grev of JavaLobby says that closures are too hard for Java developers:

Not only are the guys behind the Closure proposal very smart, they are also experts at what they do. Very probably the best in their field. They are also IMO very intelligent, which means they get the grasp of things very quickly, like most of the people hanging out here at JL I guess. The problem is that no one stands up for the normal, averagely smart "Java-Joe". There is a simple reason for this. He does something else (like having a life, ;) ) while we geeks are discussing closures and the fine print of the different syntaxes. The problem with this is that he neither have been involved in the construction of this "feature" nor has he even been asked whether it's a thing he wants or solves any of the problems he has.

Closures will make the code harder to read. That's a fact I think no one denies. It sure has its uses and I drool over the clever code I can write and that not many corporate average Joe can decode. Code that I don't understand that they don't understand.

Hmm. Here's how closures look in Smalltalk:

block := [:arg1 | someObject doSomethingWith: arg1].

to use it:

result := block value: someArgument.

Boy, that sure is hard. Looking at the Java example referenced here, there's the extra cruft of type declarations (which serve to make it somewhat harder to read IMHO - but hey - if you work in Java, you probably zone out on that anyway). To be brutal, if you can't figure out how to read code with closures, you probably can't figure out methods, functions, and subroutines either. In fact, if you can't figure out closures, you're probably the kind of person who creates one class with a method called main() - and no other classes. I've seen that kind of code in Smalltalk, and I'm sure it exists in Java too.

There's a full post on closures for Java here. There's cruft due to the need for explicit typing, but they don't look that hard. I have called them lipstick on a pig, but hey - at least they make the pig somewhat more functional.

Hat tip Blaine Buxton.

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