"viewChange" function doesnt work properly in ReplicatedHashMap.Notification<Object,Object>

When I ran the demo: ReplicatedHashMapDemo in the source code of version 3.0.9. The "viewChange" function did not always invoke when new members join.

In the demo, the title of window changes when new member joins, but actually it is:
When there is one member the title is: 'ReplicatedHashMapDemo: 1 server(s)'
When there is two members titles are: 'ReplicatedHashMapDemo: 1 server(s)','ReplicatedHashMapDemo: 2 server(s)'
When there is three members titles are: 'ReplicatedHashMapDemo: 3 server(s)','ReplicatedHashMapDemo: 2 server(s)','ReplicatedHashMapDemo: 3 server(s)'

I am not sure if this demo program can be run on one sever with multiple instance.