change return type of EngineConfiguration.replayIndexFileCapacityToBy…

…tes() to long

It's easy to overflow an int there.

artio-core/src/main/java/uk/co/real_logic/artio/engine/EngineConfiguration.java

@@ -490,15 +490,15 @@ public EngineConfiguration replayIndexSegmentRecordCapacity(final int indexSegme
 
     /**
      * Convert the number of records in a replay index file to a file size. Note: because replay index file sizes must
-     * be a power of two this method can return a file size greater than the requested number of methods but never less.
+     * be a power of two this method can return a file size greater than the requested number of records but never less.
      *
      * @param requestedNumberOfRecordsToStore the number of records to store in the replay index.
      * @return the replay index file size in bytes
      */
-    public static int replayIndexFileCapacityToBytes(final int requestedNumberOfRecordsToStore)
+    public static long replayIndexFileCapacityToBytes(final int requestedNumberOfRecordsToStore)
     {
         return HEADER_FILE_SIZE + ReplayIndexDescriptor.RECORD_LENGTH *
-            findNextPositivePowerOfTwo(requestedNumberOfRecordsToStore);
+            (long)findNextPositivePowerOfTwo(requestedNumberOfRecordsToStore);
     }
 
     /**