I do not know whether this is a new aspect of 1.5 or 1.6, but I've noticed that when I concatenate two strings using Code:
String s = "abc" + i + "def";
(where i is an integer < 10) the resulting String has array size 7. Also, Code:
new StringBuffer("abc").toString()
will give me a String size 3. So there's no need to use .concat anymore.