Java is used quite often in the business industry. You can't argue for a coin's success or failure based on the programming platform, especially when Java and C++ are concerned.
Can you give some examples of how Java is used in the business industry?
Java is used on server side by Amazon, Gmail, Ebay, and almost all banks. Try "hacking" Amazon and Gmail, the most popular server side Java apps. Oracle's Java applet (browser plugin) has security problems, but Nxt is not an applet. It's a standalone server application.