Description of problem:
It is impossible to abruptly close the InputStream used to download a glance image, in fact when close() is called the entire image is downloaded before shutting down the tcp connection.

This is a serious issue for applications such as rhevm-backend that are using the InputStream to inspect the QCOW2 header in order to discover the image virtual size.

Even more since resteasy (shipped in jboss) is using the SelfExpandingBufferredInputStream under the hood I also suspect that the entire image is not only downloaded but also cached in memory (leading to out of memory crashes).

Version-Release number of selected component (if applicable):
openstack-java-sdk-3.0.0-1.el6ev

How reproducible:
100%

Steps to Reproduce:
1. Import a large (>~2Gb) QCOW2 glance image from rhev webadmin (or rest api)

Actual results:
The entire image is downloaded (from the engine backend); the canDoAction validation takes a long time (inspecting the image virtual size).

Expected results:
Only the initial part of the image should be downloaded (resulting in a quick canDoAction and no memory usage).

Additional info:
This bug should be moved to openstack-java-sdk as soon as it will appear in the components list.