Fix Travis build for Oracle JDK 7
Fix Travis build for Oracle JDK 7

This closes #51 from GitHub.

Signed-off-by: anew <7e91e9b280c217b4c58c62b209b5ccf7d4bb217a@apache.org>

gokulavasan/incubator-tephra,gokulavasan/incubator-tephra,poornachandra/incubator-tephra,poornachandra/incubator-tephra,gokulavasan/incubator-tephra,poornachandra/incubator-tephra