If Java is your cup of tea, you might want to try Flavour. I did and now it's the only frontend framework I use. https://flavour.sourceforge.io/

It lets you write your frontend and backend code in the same language, even sharing models and validation logic so refactorings work full stack.

You get strong typing and a rich SPA framework that includes routing, templates, and easy server calls.

There's a book ( https://frequal.com/Flavour/book.html ) and a Java SwingSet-like app with live demos and source code called Tea Sampler ( https://frequal.com/tea-sampler/ ).