It appears that when using the async Java driver, if you create an AsyncBatchCursor via

cursor = collection.find(bson).batchSize(1).batchCursor(callback)

specifically using batchSize = 1, the cursor closes after a single call to next(), even when there are multiple elements to return. i.e. the second call to next() results in null. This behaviour is consistent. Changing the batchSize to > 1 resolves the problem.

I'd be grateful if somebody can confirm they can reproduce this. This looks like something really simple to have been overlooked in testing, so I want to ensure I'm not going nuts!