The interview is not that bad. The thing is that Tech-lead was asking about core Java things like how hashmap wokrs under the hood but he didn't know and couldn't listen what the possible future employee was saying and cause of that the discussion turned into something incomprehensible. One more minus is that when you can't understand the question for some reason (e.g. technical issue or the way how they're asking or maybe you're not familiar with the topic) and you're trying to ask them some questions to clarify or smth like that, they're acting like "Okay, let's start with easy things". This is so demotivational. Plus is that they're very friendly and cool if it's matter for you ;)