Золотов - Лабораторная работа #2

logger can be set to null here:
```public void setLog(final ILogger logger) {```
now your code isn't safe, because it will throw nullPointer in that case
you either need to do check ``` logger == null ``` at the ```setLogger``` method (easier) or need to do check  ``` logger == null ``` in all places where pointer to the logger is used.