question: public static int copy ( InputStream in , OutputStream out , int bufSize ) throws IOException { byte [ ] buf = new byte [ bufSize ] ; int cnt = 0 ; for ( int n ; ( n = in . read ( buf ) ) > 0 ; ) { out . write ( buf , 0 , n ) ; cnt += n ; } return cnt ; }
target:  Copies input byte stream to output byte stream.