question: protected void refillBuffer ( ) { if ( pendinglen > 0 || eof ) return ; try { offset = 0 ; pendinglen = stream . read ( buf ) ; if ( pendinglen < 0 ) { close ( ) ; return ; } else return ; } catch ( IOException e ) { throw new PngjInputException ( e ) ; } }
target:  If there are not pending bytes to be consumed tries to fill the buffer with bytes from the stream.