[SW-505] Fix Java7 problem (#353)
[SW-505] Fix Java7 problem (#353)

Related issues:
  - https://github.com/travis-ci/travis-ci/issues/7476
  - https://github.com/travis-ci/travis-ci/issues/7884
  - cause by http://www.webupd8.org/2017/06/why-oracle-java-7-and-6-installers-no.html
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