Why is React.js so hard to learn for someone from a JAVA back end background? I'm constantly asking myself "so should I set param as string? or int? Array? so many methods that's returning html tags! what collects all and makes it appear at WHERE??"

I think React is hard to learn. Period.

Vue ftw!

React is nice!
It's a little unintuitive at first, but once you get past that it's really pretty simple to use.

Best advice I can give: stop thinking in data types. It will only unnecessarily complicate things. (and they don't exist anyway)

Second best: the entire react app is a single DOM tree comprised entirely of components whose markup is determined by their render() methods. Everything else is just decoration.

@LastDigitOfPi how did you know that I just skimmed through it ?

@stacked those people who say its easy is just bluffing am i right

@Root the second part really helped. Thanks !

Learn it with typescript. But before that learn 'normal' es6. Helped me a lot

@busybeemel 😊 I'm glad!

@musician agree, TypeScript is easier to get used to if you come from a Java background. If you later get to dive into the compiled code it will just require fewer time to get used to the lack of types in JS.