Helper class that is similar to {@link java.io.ByteArrayOutputStream}in usage, but more geared to Jackson use cases internally. Specific changes include segment storage (no need to have linear backing buffer, can avoid reallocs, copying), as well API not based on {@link java.io.OutputStream}. In short, a very much specialized builder object.
Since version 1.5, also implements {@link OutputStream} to allowefficient aggregation of output content as a byte array, similar to how {@link java.io.ByteArrayOutputStream} works, but somewhat moreefficiently for many use cases.