LocationBean has scope Session, and you initialize listOfLocation in the constructor, that means that it will be initialized once in the session, that's why user 1 can't see modifications provided by user 2.
1. Store LocationBean in request scope and use a4j:keepalive (if it is necessary)
2. Implement intialization functionality (getALLLocationData()) not in the constructor of LocationBean, do it in any Action/ActionListener method...
Hope this will help you.