if(membership_listener != null)
Vector new_mbrs = v.getMembers(); if (new_mbrs != null) { members.removeAllElements(); for (int i = 0; i < new_mbrs.size(); i++) { members.addElement(new_mbrs.elementAt(i)); } }  if (membership_listener != null) {
        public void viewAccepted(View v) {            if(corr != null)                corr.receiveView(v);            Vector  new_mbrs=v.getMembers();            if(new_mbrs != null) {                members.removeAllElements();                for(int i=0; i < new_mbrs.size(); i++)                    members.addElement(new_mbrs.elementAt(i));            }            if(membership_listener != null)                membership_listener.viewAccepted(v);        }