@Override
            public void run(Status status, long index, byte[] reqCtx) {
                if(status.isOk()){
                    closure.success(getValue());
                    closure.run(Status.OK());
                    return;
                }
                CounterServiceImpl.this.readIndexExecutor.execute(() -> {
                    if(isLeader()){
                        LOG.debug("Fail to get value with 'ReadIndex': {}, try to applying to the state machine.", status);
                        applyOperation(CounterOperation.createGet(), closure);
                    }else {
                        handlerNotLeaderError(closure);
                    }
                });
            }
@author likun (saimu.msm@antfin.com)
jraft-example/src/main/java/com/alipay/sofa/jraft/example/counter/CounterServiceImpl.java