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Author: thongdk8

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataimport/processor/ImportProcessor.java

@@ -32,6 +32,7 @@
 import java.util.concurrent.Semaphore;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
+import javax.annotation.Nullable;
 import lombok.RequiredArgsConstructor;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -354,7 +355,7 @@ private ImportTransactionBatchResult processTransactionBatch(
    *
    * @param transaction the {@link DistributedTransaction} to be aborted, may be null
    */
-  private void abortTransactionSafely(DistributedTransaction transaction) {
+  private void abortTransactionSafely(@Nullable DistributedTransaction transaction) {
     try {
       if (transaction != null) {
         transaction.abort();