Refactor code according to sonar analysis results

[odockal]

I have run a local sonar analysis from sonarlint eclipse plugin and there are some places that could be refactored according to results. It might help to keep codebase clear.

[robstryker]

This doesn't really seem like an actionable issue, without details of what could be refactored, or why or how?

[odockal]

There is plenty of possible refactoring issues that could be done, listing them here has no meaning as they vary a lot. All are provided by sonar (sonarlint plugin) in IDE. My intentions here are that I will do this issue and implement a couple of PRs one by one that will address always a batch of warning/infos from sonar and let those to be discussed whether are worth enough to be merged. Should not break anything and I will learn code base a bit. @robstryker @jeffmaury wdyt?