Invoke sendAddSuccessCallbacks if no bookie will be replaced in ensemble change

Signed-off-by: guojunhao <guojunhao@bigo.sg>

Author: guojunhao

bookkeeper-server/src/main/java/org/apache/bookkeeper/client/LedgerHandle.java

@@ -2278,6 +2278,15 @@ void ensembleChangeLoop(List<BookieId> origEnsemble, Map<Integer, BookieId> fail
                         }
                         if (newEnsemble != null) { // unsetSuccess outside of lock
                             unsetSuccessAndSendWriteRequest(newEnsemble, replaced);
+                            // If replaced is empty, no one will trigger #sendAddSuccessCallbacks
+                            // in #unsetSuccessAndSendWriteRequest.
+                            // So we do need to invoke #sendAddSuccessCallbacks() for entries which
+                            // may have already completed in pendingAddOps, but are just waiting for the ensemble
+                            // to change.
+                            if (replaced.isEmpty()) {
+                                sendAddSuccessCallbacks();
+                                LOG.info("No bookie will be replaced, invoke #sendAddSuccessCallbacks.");
+                            }
                         }
                     }
             }, clientCtx.getMainWorkerPool().chooseThread(ledgerId));