Reduce technical debt add coverage

* add empty constructor message
* remove unnecessary exception declaration
* add @FunctionalInterface declaration
* switched around public static per java conventions
* fixed up JUnit ordering
* added some trivial JUnit tests to bump coverage > 70%

Issue-ID: POLICY-460
Change-Id: I13b6de29f66d692143b06180feed76dd6332d6cf
Signed-off-by: Pamela Dragosh <pdragosh@research.att.com>
8 files changed