This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
Conversion String concordinate (using +) to StingBuffer Class are no longer needed in Java 1.5?. One of my friend is saying this to me.. I tried a simple example and i can still see the performance difference... is this statement is true.
I don't know exactly what you mean with your question, but code that concatenates strings with + is still converted to operations with StringBuilder by the Java compiler in Java 5. Note that it's no longer using StringBuffer, but StringBuilder.