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Author: KodaiD

core/src/integration-test/java/com/scalar/db/storage/objectstorage/ObjectStorageAdminTestUtils.java

@@ -31,16 +31,24 @@ public void dropMetadataTable() {
 
   @Override
   public void truncateNamespacesTable() throws Exception {
-    wrapper.delete(
-        ObjectStorageUtils.getObjectKey(
-            metadataNamespace, ObjectStorageAdmin.NAMESPACE_METADATA_TABLE));
+    try {
+      wrapper.delete(
+          ObjectStorageUtils.getObjectKey(
+              metadataNamespace, ObjectStorageAdmin.NAMESPACE_METADATA_TABLE));
+    } catch (PreconditionFailedException e) {
+      // The namespace metadata table object does not exist, so do nothing
+    }
   }
 
   @Override
   public void truncateMetadataTable() throws Exception {
-    wrapper.delete(
-        ObjectStorageUtils.getObjectKey(
-            metadataNamespace, ObjectStorageAdmin.TABLE_METADATA_TABLE));
+    try {
+      wrapper.delete(
+          ObjectStorageUtils.getObjectKey(
+              metadataNamespace, ObjectStorageAdmin.TABLE_METADATA_TABLE));
+    } catch (PreconditionFailedException e) {
+      // The table metadata table object does not exist, so do nothing
+    }
   }
 
   @Override

core/src/main/java/com/scalar/db/storage/objectstorage/ObjectStorageTableMetadata.java

@@ -6,6 +6,7 @@
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Objects;
@@ -34,13 +35,17 @@ public ObjectStorageTableMetadata(
       @Nullable Map<String, String> clusteringOrders,
       @Nullable Set<String> secondaryIndexNames,
       @Nullable Map<String, String> columns) {
-    this.partitionKeyNames = partitionKeyNames != null ? partitionKeyNames : new LinkedHashSet<>();
+    this.partitionKeyNames =
+        partitionKeyNames != null ? new LinkedHashSet<>(partitionKeyNames) : new LinkedHashSet<>();
     this.clusteringKeyNames =
-        clusteringKeyNames != null ? clusteringKeyNames : new LinkedHashSet<>();
-    this.clusteringOrders = clusteringOrders != null ? clusteringOrders : Collections.emptyMap();
+        clusteringKeyNames != null
+            ? new LinkedHashSet<>(clusteringKeyNames)
+            : new LinkedHashSet<>();
+    this.clusteringOrders =
+        clusteringOrders != null ? new HashMap<>(clusteringOrders) : Collections.emptyMap();
     this.secondaryIndexNames =
-        secondaryIndexNames != null ? secondaryIndexNames : Collections.emptySet();
-    this.columns = columns != null ? columns : Collections.emptyMap();
+        secondaryIndexNames != null ? new HashSet<>(secondaryIndexNames) : Collections.emptySet();
+    this.columns = columns != null ? new HashMap<>(columns) : Collections.emptyMap();
   }
 
   public ObjectStorageTableMetadata(TableMetadata tableMetadata) {

core/src/main/java/com/scalar/db/storage/objectstorage/blob/BlobWrapper.java

@@ -119,8 +119,7 @@ public void update(String key, String object, String version)
           || e.getErrorCode().equals(BlobErrorCode.BLOB_NOT_FOUND)) {
         throw new PreconditionFailedException(
             String.format(
-                String.format(
-                    "Failed to update the object with key '%s' due to precondition failure", key)),
+                "Failed to update the object with key '%s' due to precondition failure", key),
             e);
       }
       throw new ObjectStorageWrapperException(