This was a weird one. From the strange hodgepodge of topics to the explanations themselves, it was hard to believe I'm not reading someone's blog or a self published book.
There were typos, errors, bad practices... like non-synchronized access to a lazy singleton instance after talking about how great singletons are in multi-threaded environment, or using strings instead of an enum in the factory example and a myriad of others.
Some of the examples meant to demonstrate given patterns felt completely nonsensical. The text is not much better, often being rather confusing and turning into a weird word salad. I understand there's some language barrier going on and I'm not a native speaker either, but this is where a proper editor was supposed to step in. I've heard that this is a step Packt loves to skip, though.
If you must find a use for this book, perhaps it could serve as a catalogue of things you should learn elsewhere.
Also what's up with fakespot putting this book at 100% untrustworthy reviews?