With Java 1.5 StringBuilder is preferred over StringBuffer for single
threaded access as is has less overhead.
This is evidenced by the class comment of StringBuffer and Effective
Java 2nd Edition Item 67: Avoid excessive synchronization.
> The StringBuilder class should generally be used in preference to
> this one, as it supports all of the same operations but it is faster,
> as it performs no synchronization.
- replace StringBuffer with StringBuilder where possible
Issue: BATCH-2407