It depends what you want to do. Web java is more on demand than normal java so if you want a web-dev job you should focus on web java. On the other hand, you can master normal java and be a hardcore java developer. If you focus on hardcore java it will be easy enough to go web-java. If you go web-java you will often need to turn back to normal java and read concepts and theory in order to solve web-java problems. I would suggest you to focus on web java but i won't because nowadays in web the kings are JS and python. Meaning that, with java you will be limited (probably you will have to learn js frameworks). So, i suggest you to go for a hardcore java developer.