Follow up to https://bz.apache.org/bugzilla/show_bug.cgi?id=64322
committed r1887604
the commit is just reformatting - there is still work to do to optimise the code
While the way that the blocks are fetched and the potential for the underlying to be streamed multiple times is far from ideal - I think the performance impact will depend a lot on whether the POIFSFileSystem is file backed or byte array backed. FileBackedDataSource will be affected more.
added r1887657
reverted using r1887660 due to integration test failures
I added back the changes and the integration tests passed
This is applied now as far as I see.