@Override public long[] putFileData(Object fileKey, DiskRange[] ranges, MemoryBuffer[] data, long baseOffset,
        CacheTag tag) {
      return data != null ? cache
          .putFileData(fileKey, ranges, data, baseOffset, LowLevelCache.Priority.NORMAL, null, tag) : null;
    }
Class for collecting some mocked classes.
E.g: DataCache, Allocator.BufferObjectFactory, DiskRangeListFactory
llap-server/src/test/org/apache/hadoop/hive/llap/io/LlapIoMocks.java