fix the topic offload policy param will be covered unexpected.

Author: nicklixinyang

Diff for: pulsar-broker/src/main/java/org/apache/pulsar/broker/admin/impl/PersistentTopicsBase.java

@@ -848,27 +848,28 @@ protected CompletableFuture<OffloadPoliciesImpl> internalGetOffloadPolicies(bool
             .thenCompose(op -> {
                 TopicPolicies topicPolicies = op.orElseGet(TopicPolicies::new);
                 OffloadPoliciesImpl currentOffloadPolicies = topicPolicies.getOffloadPolicies();
-                if (Objects.equals(offloadPolicies.getManagedLedgerOffloadDeletionLagInMillis(),
-                        OffloadPoliciesImpl.DEFAULT_OFFLOAD_DELETION_LAG_IN_MILLIS)) {
-                    offloadPolicies.setManagedLedgerOffloadDeletionLagInMillis(
-                            currentOffloadPolicies.getManagedLedgerOffloadDeletionLagInMillis());
-                }
-                if (Objects.equals(offloadPolicies.getManagedLedgerOffloadThresholdInBytes(),
-                        OffloadPoliciesImpl.DEFAULT_OFFLOAD_THRESHOLD_IN_BYTES)) {
-                    offloadPolicies.setManagedLedgerOffloadThresholdInBytes(
-                            currentOffloadPolicies.getManagedLedgerOffloadThresholdInBytes());
-                }
-                if (Objects.equals(offloadPolicies.getManagedLedgerOffloadMaxBlockSizeInBytes(),
-                        OffloadPoliciesImpl.DEFAULT_MAX_BLOCK_SIZE_IN_BYTES)) {
-                    offloadPolicies.setManagedLedgerOffloadMaxBlockSizeInBytes(
-                            currentOffloadPolicies.getManagedLedgerOffloadMaxBlockSizeInBytes());
-                }
-                if (Objects.equals(offloadPolicies.getManagedLedgerOffloadReadBufferSizeInBytes(),
-                        OffloadPoliciesImpl.DEFAULT_READ_BUFFER_SIZE_IN_BYTES)) {
-                    offloadPolicies.setManagedLedgerOffloadReadBufferSizeInBytes(
-                            currentOffloadPolicies.getManagedLedgerOffloadReadBufferSizeInBytes());
+                if (currentOffloadPolicies != null && offloadPolicies != null){
+                    if (Objects.equals(offloadPolicies.getManagedLedgerOffloadDeletionLagInMillis(),
+                            OffloadPoliciesImpl.DEFAULT_OFFLOAD_DELETION_LAG_IN_MILLIS)) {
+                        offloadPolicies.setManagedLedgerOffloadDeletionLagInMillis(
+                                currentOffloadPolicies.getManagedLedgerOffloadDeletionLagInMillis());
+                    }
+                    if (Objects.equals(offloadPolicies.getManagedLedgerOffloadThresholdInBytes(),
+                            OffloadPoliciesImpl.DEFAULT_OFFLOAD_THRESHOLD_IN_BYTES)) {
+                        offloadPolicies.setManagedLedgerOffloadThresholdInBytes(
+                                currentOffloadPolicies.getManagedLedgerOffloadThresholdInBytes());
+                    }
+                    if (Objects.equals(offloadPolicies.getManagedLedgerOffloadMaxBlockSizeInBytes(),
+                            OffloadPoliciesImpl.DEFAULT_MAX_BLOCK_SIZE_IN_BYTES)) {
+                        offloadPolicies.setManagedLedgerOffloadMaxBlockSizeInBytes(
+                                currentOffloadPolicies.getManagedLedgerOffloadMaxBlockSizeInBytes());
+                    }
+                    if (Objects.equals(offloadPolicies.getManagedLedgerOffloadReadBufferSizeInBytes(),
+                            OffloadPoliciesImpl.DEFAULT_READ_BUFFER_SIZE_IN_BYTES)) {
+                        offloadPolicies.setManagedLedgerOffloadReadBufferSizeInBytes(
+                                currentOffloadPolicies.getManagedLedgerOffloadReadBufferSizeInBytes());
+                    }
                 }
-
                 topicPolicies.setOffloadPolicies(offloadPolicies);
                 topicPolicies.setIsGlobal(isGlobal);
                 return pulsar().getTopicPoliciesService().updateTopicPoliciesAsync(topicName, topicPolicies);