Something confusing in source code. #5

I read the source code of jsonp-java and I found In the class 
ByteArrayServletOutputStream there is a method enlarge, why shouldn't it modify 
the count field in the class. 

The methods named setBufferSize and getBufferSize in 
HttpServletResponseContentWrapper will not get the same result because the 
setBufferSize just enlarges the buf[] array in ByteArrayServletOutputStream 
instance buffer without modifing the count field in buffer and getBufferSize 
just return the count field of ByteArrayServletOutputStream instance.