You're mistaken. For 90% of all programming tasks, Java runs just as fast as C++.
Java 'Just In Time' VMs actually compile the Java code into native binaries and then execute them. There is no difference in how they execute. The *only* difference is that Java isn't set up to handle serious number crunching and massive amounts of I/O, because we've found that 90% of all software doesn't need to calculate more than 1,000,000 times a second.
You clearly are going on what you were told about Java, and have not looked at it, I'm afraid.
I think *that* may be why you get so much push back on your Java criticism. If you're just uninformed . . .