#groovy-stream

[bloidonia]

groovy-stream updates and Java integration

So a quick post about the latest release (0.8.0) of groovy-stream.

In a nutshell, this update has removed a couple of things, and added support for using groovy-stream from Java.

Farewell to the old

So first up, the things that are gone. Firstly something that I keep coming back to and getting wrong is asSynchronized. Synchronizing Iterators is hard. And I got it wrong again, so it's gone (again)

Secondly a lot of the remove calls have been errr... removed as despite removing something, it was hard to tell what was going to be removed (as some iterators cache the next element internally when hasNext is called), so I've changed them to throw an UnsupportedOperationException to save confusion.

Thirdly, Stream no longer implements Iterable.

Iterable implies iterator() can be called multiple times to start iterating again. But with Stream, this wouldn't happen. SO again, it's been removed as a potential source of confusion.

And hello to the new!

As for what is new, it's the fact that you can now use groovy-stream from Java.

So, for a contrived example lets say we x which can be 1, 2 or 3, and y which can be 4, 5 or 6.

Then, we want to get all possible sums of x and y where the result is odd.

In Java, we can declare our map for x and y then, we can declare a Stream which adds these two together, and only returns the odd values:

Mmmm...delicious verbosity ;-)

Of course, this verbosity drops when you move to Java 8

Oh and btw, with Groovy, it's cleaner still (thanks to delegation, List and Map literals and boolean coercion)

Enjoy!

@tim_yates

[bloidonia]

Rock Paper Scissors with Groovy-stream

Anyway, on to the code

@tim_yates