A DESCRIPTION OF THE REQUEST :
Since Java 5.0, StringBuilder has been introduced.
This is a great performance enhancement in server application.

A lot of java.* et javax.* still use old synchronized StringBuffer with no need as
java.net.URLDecoder.decode(String, String) for exemple.

It just can be simply replaced by StringBuilder instead.


JUSTIFICATION :
Synchronisation is costly, especially in high load multithreaded application wich are developped to limit synchronisation cost.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Replace StringBuffer by StringBuilder in the Java APIs where no synchronisation is needed.