AbstractJSONDataSource#getJSONString() and buffering

The method getJSONString() in AbstractJSONDataSource makes
use of string concatenation instead of using a buffer (e.g. StringBuilder).

char temp = (char)jsonReader.read();
jsonString = "";
while ((int)temp != 65535)

{ jsonString += temp; temp = (char)jsonReader.read(); }

A buffer would be nice for printing large JSON-strings (e.g. with 40000 characters)
or a printing a lot of middle-sized JSON-strings.

char temp = (char)jsonReader.read();
StringBuilder sb = new StringBuilder(100); // TODO which initial capacity?
while ((int)temp != 65535)

{ sb.append(temp); temp = (char)jsonReader.read(); }

jsonString = sb.toString();