Reactive collections as implemented in
are reactive adapters for Java collections.
Reactive collections wrap Java collections and turn them into reactive data source as long as all accesses are mediated by the wrapper.
Reactive collections will wake up dependent reactive computations whenever relevant write is made to the collection.
Reactive collections are included in core library.
ReactiveCollections class in javadoc.
Since the javadoc is not complete yet, you might want to take a look at comments and implementation