Fix potential integer overflow in BufferArrayGrouper (#9605)

This change fixes a potential integer overflow in BufferArrayGrouper that
was flagged by LGTM. It also adds a check that the vectorized arrays are
initialized before aggregateVector is called.

The changes in HashTableUtils should not have any effect since the numbers
being multiplied are small, but the change will remove the warnings from
being flagged in LGTM.

processing/src/main/java/org/apache/druid/query/groupby/epinephelinae/BufferArrayGrouper.java

@@ -191,6 +191,10 @@ public class BufferArrayGrouper implements VectorGrouper, IntGrouper
       throw new ISE("keySpace too large to handle");
     }
 
+    if (vAggregationPositions == null || vAggregationRows == null) {
+      throw new ISE("Grouper was not initialized for vectorization");
+    }
+
     if (keySpace.getCapacity() == 0) {
       // Empty key space, assume keys are all zeroes.
       final int dimIndex = 1;
@@ -206,7 +210,7 @@ public class BufferArrayGrouper implements VectorGrouper, IntGrouper
     } else {
       for (int i = 0; i < numRows; i++) {
         // +1 matches what hashFunction() would do.
-        final int dimIndex = keySpace.getInt(i * Integer.BYTES) + 1;
+        final int dimIndex = keySpace.getInt(((long) i) * Integer.BYTES) + 1;
 
         if (dimIndex < 0 || dimIndex >= cardinalityWithMissingValue) {
           throw new IAE("Invalid dimIndex[%s]", dimIndex);

processing/src/main/java/org/apache/druid/query/groupby/epinephelinae/collection/HashTableUtils.java

@@ -65,19 +65,19 @@ public class HashTableUtils
 
       case 9:
         return 31 * (31 * (31 + memory.getInt(position)) + memory.getInt(position + Integer.BYTES))
-               + memory.getByte(position + 2 * Integer.BYTES);
+               + memory.getByte(position + 2L * Integer.BYTES);
 
       case 12:
         return 31 * (31 * (31 + memory.getInt(position)) + memory.getInt(position + Integer.BYTES))
-               + memory.getInt(position + 2 * Integer.BYTES);
+               + memory.getInt(position + 2L * Integer.BYTES);
 
       case 13:
         return 31 * (31 * (31 * (31 + memory.getInt(position)) + memory.getInt(position + Integer.BYTES))
-                     + memory.getInt(position + 2 * Integer.BYTES)) + memory.getByte(position + 3 * Integer.BYTES);
+                     + memory.getInt(position + 2L * Integer.BYTES)) + memory.getByte(position + 3L * Integer.BYTES);
 
       case 16:
         return 31 * (31 * (31 * (31 + memory.getInt(position)) + memory.getInt(position + Integer.BYTES))
-                     + memory.getInt(position + 2 * Integer.BYTES)) + memory.getInt(position + 3 * Integer.BYTES);
+                     + memory.getInt(position + 2L * Integer.BYTES)) + memory.getInt(position + 3L * Integer.BYTES);
 
       default:
         int hashCode = 1;