Phil Hudson suggested in Feburary 2009 that "[FastStringBuffer] should
be removed with all references to it replaced with
java.lang.StringBuilder once enough confidence in this change has been
gained." After almost a year of using FastStringBuffer as a delagate
for StringBuilder, that confidence has indeed been gained.
One subtlety for use of StringBuilder: there is no
constructor, so use
to construct a new StringBuilder containing a single char. Otherwise
that char will get promoted to an int, and you will invoke
which will "swallow" the first character that you thought you were adding.