public RaftGroupService RaftGroupService() {
        return this.raftGroupService;
    }
Counter server that keeps a counter value in a raft group.

@author boyan (boyan@alibaba-inc.com)
<p>
2018-Apr-09 4:51:02 PM
jraft-example/src/main/java/com/alipay/sofa/jraft/example/counter/CounterServer.java