* Fix typos.
* Remove unnecessary boxing/unboxing.
* Replace traditional 'for' loops with 'foreach' loops.
* Replace explicit types with <> (diamonds) where they can be inferred.
* Collapse identical catch branches.
* Replace statement lambda with expression lambda for short statements.
* Remove unnecessary imports.
* Replace some lambdas with Comparator.comparing
* Replace Runnables with lambdas.
* Use addAll instead of adding whole collection manually.
* Simplify boolean expressions.
* Remove redundant 'else'.
* Simplify some boolean conditions that are always true or false.
* Inline redundant local variables.
* Remove extraneous semicolons.
* Fix Javadoc errors.
* Replace anonymous classes with lambdas.
* Replace chain of 'if's with switch.
* Remove delaration of exception that is never thrown.
* Use String/StringBuilder properly.