Today I was reading Antonio's Blog about toString() performance and there is a paragraph:
What used to be considered evil yesterday (“do not concatenate Strings with + !!!“), has become cool and efficient! Today the JVM compiles the + symbol into a string builder (in most cases). So, do not hesitate, use it.
Now I am confused, because he is saying Today the JVM compiles the + symbol into a string builder (in most cases), but I have never heard or seen(code) anything like this before.
Could someone please give example where JVM does this and in what conditions it happens?