question: public void writeToStream ( OutputStream os , int len ) throws IOException { while ( len > 0 ) { if ( _readLength <= _readOffset ) { if ( ! readBuffer ( ) ) return ; } int sublen = Math . min ( len , _readLength - _readOffset ) ; os . write ( _readBuffer , _readOffset , sublen ) ; _readOffset += sublen ; len -= sublen ; } }
target:  Writes <code>len<code> bytes to the output stream from this stream.