@Override
                    public void run(final Status status) {
                        RecycleUtil.recycle(recyclable); // TODO: recycle on send success, not response received.
                        onRpcReturned(Replicator.this.id, RequestType.AppendEntries, status, header, getResponse(),
                            seq, v, monotonicSendTimeMs);
                    }
Send log entries to follower, returns true when success, otherwise false and unlock the id.

@param nextSendingIndex next sending index
@return send result.
jraft-core/src/main/java/com/alipay/sofa/jraft/core/Replicator.java