Select2MultiChoice.java:55 uses Collections.emptyList() in order to clear the list of choices.
The problem he is, that we introduce a Collection no longer capable of adding elements to it.
This is only relevant, if the underlying object is not marshalled in a way the disassembles and reassembles the list anyway (JPA, most non-serializing persistence mechanisms).
We keep our stuff in RAM, so this breaks our code when first clearing the list and then adding something again.
I'd suggest new ArrayList() instead of Collections.emptyList();
Issue #25: Don't use Collections.emptyList() to clear choices
looks like everything has been merged. closing.