Extract dataNode.size out of the for loop

It is (hopefully!) not going to change during iteration.
Extract the all-nodes string to local constant

Hopefully this makes it more prominent versus burying it inside the for loop
Continue on error instead of throwing exception

Based on feedback by @jpountz
Specifically catch NFE versus catch-all

This commit does not re-indent the block in order to make the actual change more apparent. I will re-indent the block in the next commit.

This was based on feedback by @jpountz
Whitespace change due to removing try-catch
Use log formatting instead of String.format

Previously that message was used twice, but now that it is only used in the log, go ahead and use the log formatting mechanism
Remove quotes from log message

It seems none of the rest of the log messages use quotes, and use array brackets instead. This just harmonizes things.
Make the log message less stuffy