All I know is, first, the product is not good-looking, and it takes more effort to look good. Second, the efficiency is very low, a button stands in a place with a lot of memory, and java has its own garbage collection mechanism, so the program will run faster and faster. Third, the market share is too low. The advantage of java is cross-platform, so most people focus on this advantage. Most GUI runs on windows, and c++ has great advantages.