@fatimasajjad : It's no really a response, but moretheless to try to understand. Do you have the problem if you use a pure Java browser (https://github.com/LoboEvolution/LoboEvolution)
What if you try wget or curl ?
I'm facing the same issue after Tom90 migration, and i have this problem only on very small file (<50bytes). The files are truncated on normal browsers, but are fully downloaded with curl or LoboEvo.